1
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Drmota P, Nadlinger DP, Main D, Nichol BC, Ainley EM, Leichtle D, Mantri A, Kashefi E, Srinivas R, Araneda G, Ballance CJ, Lucas DM. Verifiable Blind Quantum Computing with Trapped Ions and Single Photons. Phys Rev Lett 2024; 132:150604. [PMID: 38682960 DOI: 10.1103/physrevlett.132.150604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 01/16/2024] [Indexed: 05/01/2024]
Abstract
We report the first hybrid matter-photon implementation of verifiable blind quantum computing. We use a trapped-ion quantum server and a client-side photonic detection system networked via a fiber-optic quantum link. The availability of memory qubits and deterministic entangling gates enables interactive protocols without postselection-key requirements for any scalable blind server, which previous realizations could not provide. We quantify the privacy at ≲0.03 leaked classical bits per qubit. This experiment demonstrates a path to fully verified quantum computing in the cloud.
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Affiliation(s)
- P Drmota
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - D P Nadlinger
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - D Main
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - B C Nichol
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - E M Ainley
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - D Leichtle
- Laboratoire d'Informatique de Paris 6, CNRS, Sorbonne Université, Paris 75005, France
| | - A Mantri
- Joint Center for Quantum Information and Computer Science, University of Maryland, College Park, Maryland, USA
| | - E Kashefi
- Laboratoire d'Informatique de Paris 6, CNRS, Sorbonne Université, Paris 75005, France
- School of Informatics, University of Edinburgh, Edinburgh EH8 9AB, United Kingdom
| | - R Srinivas
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - G Araneda
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - C J Ballance
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - D M Lucas
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
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2
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Saner S, Băzăvan O, Minder M, Drmota P, Webb DJ, Araneda G, Srinivas R, Lucas DM, Ballance CJ. Breaking the Entangling Gate Speed Limit for Trapped-Ion Qubits Using a Phase-Stable Standing Wave. Phys Rev Lett 2023; 131:220601. [PMID: 38101375 DOI: 10.1103/physrevlett.131.220601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 10/16/2023] [Indexed: 12/17/2023]
Abstract
All laser-driven entangling operations for trapped-ion qubits have hitherto been performed without control of the optical phase of the light field, which precludes independent tuning of the carrier and motional coupling. By placing ^{88}Sr^{+} ions in a λ=674 nm standing wave, whose relative position is controlled to ≈λ/100, we suppress the carrier coupling by a factor of 18, while coherently enhancing the spin-motion coupling. We experimentally demonstrate that the off-resonant carrier coupling imposes a speed limit for conventional traveling-wave Mølmer-Sørensen gates; we use the standing wave to surpass this limit and achieve a gate duration of 15 μs, restricted by the available laser power.
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Affiliation(s)
- S Saner
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - O Băzăvan
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - M Minder
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - P Drmota
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - D J Webb
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - G Araneda
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - R Srinivas
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - D M Lucas
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - C J Ballance
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
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3
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Srinivas R, Löschnauer CM, Malinowski M, Hughes AC, Nourshargh R, Negnevitsky V, Allcock DTC, King SA, Matthiesen C, Harty TP, Ballance CJ. Coherent Control of Trapped-Ion Qubits with Localized Electric Fields. Phys Rev Lett 2023; 131:020601. [PMID: 37505962 DOI: 10.1103/physrevlett.131.020601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 05/23/2023] [Indexed: 07/30/2023]
Abstract
We present a new method for coherent control of trapped ion qubits in separate interaction regions of a multizone trap by simultaneously applying an electric field and a spin-dependent gradient. Both the phase and amplitude of the effective single-qubit rotation depend on the electric field, which can be localized to each zone. We demonstrate this interaction on a single ion using both laser-based and magnetic-field gradients in a surface-electrode ion trap, and measure the localization of the electric field.
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Affiliation(s)
- R Srinivas
- Oxford Ionics, Oxford, OX5 1PF, United Kingdom
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, United Kingdom
| | | | | | - A C Hughes
- Oxford Ionics, Oxford, OX5 1PF, United Kingdom
| | | | | | - D T C Allcock
- Oxford Ionics, Oxford, OX5 1PF, United Kingdom
- Department of Physics, University of Oregon, Eugene, Oregon 97403, USA
| | - S A King
- Oxford Ionics, Oxford, OX5 1PF, United Kingdom
| | | | - T P Harty
- Oxford Ionics, Oxford, OX5 1PF, United Kingdom
| | - C J Ballance
- Oxford Ionics, Oxford, OX5 1PF, United Kingdom
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, United Kingdom
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4
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Drmota P, Main D, Nadlinger DP, Nichol BC, Weber MA, Ainley EM, Agrawal A, Srinivas R, Araneda G, Ballance CJ, Lucas DM. Robust Quantum Memory in a Trapped-Ion Quantum Network Node. Phys Rev Lett 2023; 130:090803. [PMID: 36930909 DOI: 10.1103/physrevlett.130.090803] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
We integrate a long-lived memory qubit into a mixed-species trapped-ion quantum network node. Ion-photon entanglement first generated with a network qubit in ^{88}Sr^{+} is transferred to ^{43}Ca^{+} with 0.977(7) fidelity, and mapped to a robust memory qubit. We then entangle the network qubit with a second photon, without affecting the memory qubit. We perform quantum state tomography to show that the fidelity of ion-photon entanglement decays ∼70 times slower on the memory qubit. Dynamical decoupling further extends the storage duration; we measure an ion-photon entanglement fidelity of 0.81(4) after 10 s.
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Affiliation(s)
- P Drmota
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - D Main
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - D P Nadlinger
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - B C Nichol
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - M A Weber
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - E M Ainley
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - A Agrawal
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - R Srinivas
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - G Araneda
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - C J Ballance
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - D M Lucas
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
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5
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Nichol BC, Srinivas R, Nadlinger DP, Drmota P, Main D, Araneda G, Ballance CJ, Lucas DM. An elementary quantum network of entangled optical atomic clocks. Nature 2022; 609:689-694. [PMID: 36071166 DOI: 10.1038/s41586-022-05088-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 07/07/2022] [Indexed: 11/09/2022]
Abstract
Optical atomic clocks are our most precise tools to measure time and frequency1-3. Precision frequency comparisons between clocks in separate locations enable one to probe the space-time variation of fundamental constants4,5 and the properties of dark matter6,7, to perform geodesy8-10 and to evaluate systematic clock shifts. Measurements on independent systems are limited by the standard quantum limit; measurements on entangled systems can surpass the standard quantum limit to reach the ultimate precision allowed by quantum theory-the Heisenberg limit. Although local entangling operations have demonstrated this enhancement at microscopic distances11-16, comparisons between remote atomic clocks require the rapid generation of high-fidelity entanglement between systems that have no intrinsic interactions. Here we report the use of a photonic link17,18 to entangle two 88Sr+ ions separated by a macroscopic distance19 (approximately 2 m) to demonstrate an elementary quantum network of entangled optical clocks. For frequency comparisons between the ions, we find that entanglement reduces the measurement uncertainty by nearly [Formula: see text], the value predicted for the Heisenberg limit. Today's optical clocks are typically limited by dephasing of the probe laser20; in this regime, we find that entanglement yields a factor of 2 reduction in the measurement uncertainty compared with conventional correlation spectroscopy techniques20-22. We demonstrate this enhancement for the measurement of a frequency shift applied to one of the clocks. This two-node network could be extended to additional nodes23, to other species of trapped particles or-through local operations-to larger entangled systems.
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Affiliation(s)
- B C Nichol
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, UK.
| | - R Srinivas
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, UK.
| | - D P Nadlinger
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - P Drmota
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - D Main
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - G Araneda
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - C J Ballance
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - D M Lucas
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, UK
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6
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Nadlinger DP, Drmota P, Nichol BC, Araneda G, Main D, Srinivas R, Lucas DM, Ballance CJ, Ivanov K, Tan EYZ, Sekatski P, Urbanke RL, Renner R, Sangouard N, Bancal JD. Experimental quantum key distribution certified by Bell's theorem. Nature 2022; 607:682-686. [PMID: 35896644 DOI: 10.1038/s41586-022-04941-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 06/07/2022] [Indexed: 11/09/2022]
Abstract
Cryptographic key exchange protocols traditionally rely on computational conjectures such as the hardness of prime factorization1 to provide security against eavesdropping attacks. Remarkably, quantum key distribution protocols such as the Bennett-Brassard scheme2 provide information-theoretic security against such attacks, a much stronger form of security unreachable by classical means. However, quantum protocols realized so far are subject to a new class of attacks exploiting a mismatch between the quantum states or measurements implemented and their theoretical modelling, as demonstrated in numerous experiments3-6. Here we present the experimental realization of a complete quantum key distribution protocol immune to these vulnerabilities, following Ekert's pioneering proposal7 to use entanglement to bound an adversary's information from Bell's theorem8. By combining theoretical developments with an improved optical fibre link generating entanglement between two trapped-ion qubits, we obtain 95,628 key bits with device-independent security9-12 from 1.5 million Bell pairs created during eight hours of run time. We take steps to ensure that information on the measurement results is inaccessible to an eavesdropper. These measurements are performed without space-like separation. Our result shows that provably secure cryptography under general assumptions is possible with real-world devices, and paves the way for further quantum information applications based on the device-independence principle.
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Affiliation(s)
- D P Nadlinger
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK.
| | - P Drmota
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
| | - B C Nichol
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
| | - G Araneda
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
| | - D Main
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
| | - R Srinivas
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
| | - D M Lucas
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
| | - C J Ballance
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK.
| | - K Ivanov
- School of Computer and Communication Sciences, EPFL, Lausanne, Switzerland
| | - E Y-Z Tan
- Institute for Theoretical Physics, ETH Zürich, Zürich, Switzerland
| | - P Sekatski
- Department of Applied Physics, University of Geneva, Geneva, Switzerland
| | - R L Urbanke
- School of Computer and Communication Sciences, EPFL, Lausanne, Switzerland
| | - R Renner
- Institute for Theoretical Physics, ETH Zürich, Zürich, Switzerland
| | - N Sangouard
- Université Paris-Saclay, CEA, CNRS, Institut de Physique Théorique, Gif-sur-Yvette, France.
| | - J-D Bancal
- Université Paris-Saclay, CEA, CNRS, Institut de Physique Théorique, Gif-sur-Yvette, France.
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7
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Srinivas R, Naleer M, Kumar K. Assessment of cognition in chronic subdural hematoma patients using MMSE in preoperative and postoperative periods. Interdisciplinary Neurosurgery 2022. [DOI: 10.1016/j.inat.2022.101515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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8
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Shah U, Rahulan V, Srinivas R, Kumar S, Anoop Mohandas K, Kori S, Panda S, Singh V, Kumar P, Prasanna G, Satish Rao I, Kalle A, Manish D, John PA, Mahesh B, Dutta P, Attawar S. Clinico-radiological-pathological profile and outcomes of Lung transplantation in post covid-19 phenotype: A single centre experience. Transplant Proc 2022; 54:1494-1503. [PMID: 35654635 PMCID: PMC8995303 DOI: 10.1016/j.transproceed.2022.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 03/07/2022] [Indexed: 01/08/2023]
Abstract
Background Lung transplantation (LTx) has come as hope for select patients with post-COVID acute respiratory distress syndrome (ARDS). It has a different phenotype with unique challenges. We aimed to bring out our experience with and outcomes of LTx for post-COVID ARDS. Methods This study is retrospective case series from a single center in India. All the patients with post-COVID end stage lung disease (ESLD) who underwent bilateral LTx between 1st May 2020 and 30th August 2021 were included. LTx was performed following no improvement with optimal medical management with adequate time provided for recovery. Information relating to demographics, comorbidities, pretransplant status, perioperative parameters, gross and histopathological findings of explanted lungs, posttransplant morbidity, and mortality were analyzed. Results This study included 23 patients. The median age of the patients in this study was 42 years and 20 participants were men (87%). The mean duration of intensive care unit stay was 15.83 ± 6.61 days. Mortality was observed among 8 participants (34.78%). Mean survival time was 34.54 weeks. Among the 8 patients who expired, the cause of death was sepsis for 6 patients (75.0%), neurologic cerebrovascular accident for 1 patient (12.5%), and cytomegalovirus for 1 patient (12.5%). All the deaths were reported in primary graft dysfunction grade 2 & 3 category. No rejections were observed on first and third month surveillance biopsies. Conclusions LTx is the definitive option for survival in select patients with severe post–COVID-19–associated ESLD. This study brings out various challenges involved in such phenotypes and also observations in postoperative recovery.
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9
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Srinivas R, Burd SC, Knaack HM, Sutherland RT, Kwiatkowski A, Glancy S, Knill E, Wineland DJ, Leibfried D, Wilson AC, Allcock DTC, Slichter DH. High-fidelity laser-free universal control of trapped ion qubits. Nature 2021; 597:209-213. [PMID: 34497396 DOI: 10.1038/s41586-021-03809-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 07/07/2021] [Indexed: 11/09/2022]
Abstract
Universal control of multiple qubits-the ability to entangle qubits and to perform arbitrary individual qubit operations1-is a fundamental resource for quantum computing2, simulation3 and networking4. Qubits realized in trapped atomic ions have shown the highest-fidelity two-qubit entangling operations5-7 and single-qubit rotations8 so far. Universal control of trapped ion qubits has been separately demonstrated using tightly focused laser beams9-12 or by moving ions with respect to laser beams13-15, but at lower fidelities. Laser-free entangling methods16-20 may offer improved scalability by harnessing microwave technology developed for wireless communications, but so far their performance has lagged the best reported laser-based approaches. Here we demonstrate high-fidelity laser-free universal control of two trapped-ion qubits by creating both symmetric and antisymmetric maximally entangled states with fidelities of [Formula: see text] and [Formula: see text], respectively (68 per cent confidence level), corrected for initialization error. We use a scheme based on radiofrequency magnetic field gradients combined with microwave magnetic fields that is robust against multiple sources of decoherence and usable with essentially any trapped ion species. The scheme has the potential to perform simultaneous entangling operations on multiple pairs of ions in a large-scale trapped-ion quantum processor without increasing control signal power or complexity. Combining this technology with low-power laser light delivered via trap-integrated photonics21,22 and trap-integrated photon detectors for qubit readout23,24 provides an opportunity for scalable, high-fidelity, fully chip-integrated trapped-ion quantum computing.
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Affiliation(s)
- R Srinivas
- National Institute of Standards and Technology, Boulder, CO, USA. .,Department of Physics, University of Colorado, Boulder, CO, USA. .,Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, UK.
| | - S C Burd
- National Institute of Standards and Technology, Boulder, CO, USA.,Department of Physics, University of Colorado, Boulder, CO, USA.,Department of Physics, Stanford University, Stanford, CA, USA
| | - H M Knaack
- National Institute of Standards and Technology, Boulder, CO, USA.,Department of Physics, University of Colorado, Boulder, CO, USA
| | - R T Sutherland
- Physics Division, Physical and Life Sciences, Lawrence Livermore National Laboratory, Livermore, CA, USA.,Department of Electrical and Computer Engineering, University of Texas at San Antonio, San Antonio, TX, USA.,Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, TX, USA
| | - A Kwiatkowski
- National Institute of Standards and Technology, Boulder, CO, USA.,Department of Physics, University of Colorado, Boulder, CO, USA
| | - S Glancy
- National Institute of Standards and Technology, Boulder, CO, USA
| | - E Knill
- National Institute of Standards and Technology, Boulder, CO, USA.,Center for Theory of Quantum Matter, University of Colorado, Boulder, CO, USA
| | - D J Wineland
- National Institute of Standards and Technology, Boulder, CO, USA.,Department of Physics, University of Colorado, Boulder, CO, USA.,Department of Physics, University of Oregon, Eugene, OR, USA
| | - D Leibfried
- National Institute of Standards and Technology, Boulder, CO, USA
| | - A C Wilson
- National Institute of Standards and Technology, Boulder, CO, USA
| | - D T C Allcock
- National Institute of Standards and Technology, Boulder, CO, USA.,Department of Physics, University of Colorado, Boulder, CO, USA.,Department of Physics, University of Oregon, Eugene, OR, USA
| | - D H Slichter
- National Institute of Standards and Technology, Boulder, CO, USA.
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10
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Udutha S, Borkar RM, Shankar G, Sony T, Jala A, Vamshi Krisna E, Kiran Kumar T, Misra S, Prabhakar S, Srinivas R. Stress degradation study of bortezomib: effect of co-solvent, isolation and characterization of degradation products by UHPLC-Q-TOF-MS/MS and NMR and evaluation of the toxicity of the degradation products. NEW J CHEM 2021. [DOI: 10.1039/d0nj05781a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Bortezomib (BTZ) is a first-in-class, potent reversible inhibitor of proteasome used in the treatment of multiple myeloma, the second most common hematological cancer.
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Affiliation(s)
- Suresh Udutha
- Analytical & Structural Chemistry Department
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
- Academy of Scientific and Innovative Research (AcSIR)
| | - Roshan M. Borkar
- Department of Pharmaceutical Analysis
- National Institute of Pharmaceutical Education and Research (NIPER)
- Changsari
- India
| | - G. Shankar
- Analytical & Structural Chemistry Department
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - T. Sony
- Analytical & Structural Chemistry Department
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - Aishwarya Jala
- Department of Pharmaceutical Analysis
- National Institute of Pharmaceutical Education and Research (NIPER)
- Changsari
- India
| | - E. Vamshi Krisna
- Centre for Natural Products & Traditional knowledge
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - T. Kiran Kumar
- Applied Biology Division
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - S. Misra
- Centre for Natural Products & Traditional knowledge
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - S. Prabhakar
- Analytical & Structural Chemistry Department
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
- Academy of Scientific and Innovative Research (AcSIR)
| | - R. Srinivas
- Analytical & Structural Chemistry Department
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
- Academy of Scientific and Innovative Research (AcSIR)
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11
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Burd SC, Srinivas R, Bollinger JJ, Wilson AC, Wineland DJ, Leibfried D, Slichter DH, Allcock DTC. Quantum amplification of mechanical oscillator motion. Science 2019; 364:1163-1165. [DOI: 10.1126/science.aaw2884] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 04/11/2019] [Indexed: 11/02/2022]
Affiliation(s)
- S. C. Burd
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, USA
- Department of Physics, University of Colorado, Boulder, CO 80309, USA
| | - R. Srinivas
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, USA
- Department of Physics, University of Colorado, Boulder, CO 80309, USA
| | - J. J. Bollinger
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - A. C. Wilson
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - D. J. Wineland
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, USA
- Department of Physics, University of Colorado, Boulder, CO 80309, USA
- Department of Physics, University of Oregon, Eugene, OR 97403, USA
| | - D. Leibfried
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - D. H. Slichter
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - D. T. C. Allcock
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, USA
- Department of Physics, University of Colorado, Boulder, CO 80309, USA
- Department of Physics, University of Oregon, Eugene, OR 97403, USA
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12
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Srinivas R, Burd SC, Sutherland RT, Wilson AC, Wineland DJ, Leibfried D, Allcock DTC, Slichter DH. Trapped-Ion Spin-Motion Coupling with Microwaves and a Near-Motional Oscillating Magnetic Field Gradient. Phys Rev Lett 2019; 122:163201. [PMID: 31075007 PMCID: PMC6662926 DOI: 10.1103/physrevlett.122.163201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Indexed: 06/09/2023]
Abstract
We present a new method of spin-motion coupling for trapped ions using microwaves and a magnetic field gradient oscillating close to the ions' motional frequency. We demonstrate and characterize this coupling experimentally using a single ion in a surface-electrode trap that incorporates current-carrying electrodes to generate the microwave field and the oscillating magnetic field gradient. Using this method, we perform resolved-sideband cooling of a single motional mode to its ground state.
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Affiliation(s)
- R. Srinivas
- Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA
- Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
| | - S. C. Burd
- Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA
- Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
| | - R. T. Sutherland
- Physics Division, Physical and Life Sciences, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - A. C. Wilson
- Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA
| | - D. J. Wineland
- Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA
- Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
- Department of Physics, University of Oregon, Eugene, Oregon 97403, USA
| | - D. Leibfried
- Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA
| | - D. T. C. Allcock
- Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA
- Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
- Department of Physics, University of Oregon, Eugene, Oregon 97403, USA
| | - D. H. Slichter
- Time and Frequency Division, National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA
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13
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Cyriac J, Paulose J, George M, Srinivas R, Giblin D, Gross ML. Protonation of Curcumin Triggers Sequential Double Cyclization in the Gas-Phase: An Electrospray Mass Spectrometry and DFT Study. Int J Mass Spectrom 2019; 438:107-114. [PMID: 31080356 PMCID: PMC6508607 DOI: 10.1016/j.ijms.2019.01.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
ESI-protonated natural curcumin (1) undergoes gas-phase cyclization and dissociates via competitive expulsions of 2-methoxy phenol and C4H4O2 (diketene or an isomer). Evidence from mechanistic mass spectrometry and from Density Functional Theory (DFT) reveals that a two-step sequential cyclization occurs for the protonated molecule prior to the unusual loss of the elements of 2-methoxy phenol. Furthermore, the presence of the methoxy group at postion-3 is essential for the second cyclization. The transformation of curcumin upon protonation in the gas phase may be predictive of its solution chemistry and explain how curcumin plays a protective role in biology.
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Affiliation(s)
- June Cyriac
- Department of Chemistry, Sacred Heart College, Thevara, Kochi, Kerala, India
| | - Justin Paulose
- Department of Chemistry, Sacred Heart College, Thevara, Kochi, Kerala, India
| | - M George
- Department of Chemistry, Sacred Heart College, Thevara, Kochi, Kerala, India
| | - R Srinivas
- National center for Mass Spectrometry, IICT, Hyderabad, India
| | - Daryl Giblin
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130
| | - Michael L Gross
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130
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14
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Abstract
Trityl ethers are chemoselectively deprotected to the corresponding alcohols in high yields by a catalytic amount of indium tribromide in aqueous acetonitrile. The method is compatible with various functional groups such as acetonides, acetates, benzoates, olefins, carbamates, esters and ethers present in the substrate.
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Affiliation(s)
- J.S. Yadav
- Division of Organic Chemistry -I, Indian Institute of Chemical Technology, Hyderabad-500007, India
| | - B.V.Subba Reddy
- Division of Organic Chemistry -I, Indian Institute of Chemical Technology, Hyderabad-500007, India
| | - R. Srinivas
- Division of Organic Chemistry -I, Indian Institute of Chemical Technology, Hyderabad-500007, India
| | - A. Maiti
- Division of Organic Chemistry -I, Indian Institute of Chemical Technology, Hyderabad-500007, India
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15
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Srinivas R, Reddy BS, Yadav J, Ramalingam T. An Efficient and Selective conversion of Hydrazides into Esters and Acids. Journal of Chemical Research 2019. [DOI: 10.3184/030823400103167958] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hydrazides are selectively oxidised to esters/acids in high yields using Oxone® in the presence of an appropriate alcohol/water as a nucleophile at ambient temperature. A variety of functional groups including alkenes, alcohols, ethers, cyclopropyl groups and nitriles are unaffected.
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Affiliation(s)
- R. Srinivas
- Organic Chemistry Division-I, Indian Institute of Chemical Technology, Hyderabad-500 007, India
| | - B.V. Subba Reddy
- Organic Chemistry Division-I, Indian Institute of Chemical Technology, Hyderabad-500 007, India
| | - J.S. Yadav
- Organic Chemistry Division-I, Indian Institute of Chemical Technology, Hyderabad-500 007, India
| | - T. Ramalingam
- Organic Chemistry Division-I, Indian Institute of Chemical Technology, Hyderabad-500 007, India
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16
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Sutherland RT, Srinivas R, Burd SC, Leibfried D, Wilson AC, Wineland DJ, Allcock DTC, Slichter DH, Libby SB. Versatile laser-free trapped-ion entangling gates. New J Phys 2019; 21:10.1088/1367-2630/ab0be5. [PMID: 31555055 PMCID: PMC6759860 DOI: 10.1088/1367-2630/ab0be5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We present a general theory for laser-free entangling gates with trapped-ion hyperfine qubits, using either static or oscillating magnetic-field gradients combined with a pair of uniform microwave fields symmetrically detuned about the qubit frequency. By transforming into a 'bichromatic' interaction picture, we show that eitherσ ^ ϕ ⊗ σ ^ ϕ orσ ^ z ⊗ σ ^ z geometric phase gates can be performed. The gate basis is determined by selecting the microwave detuning. The driving parameters can be tuned to provide intrinsic dynamical decoupling from qubit frequency fluctuations. Theσ ^ z ⊗ σ ^ z gates can be implemented in a novel manner which eases experimental constraints. We present numerical simulations of gate fidelities assuming realistic parameters.
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Affiliation(s)
- R T Sutherland
- Physics Division, Physical and Life Sciences, Lawrence Livermore National Laboratory, Livermore, CA 94550, United States of America
| | - R Srinivas
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, United States of America
- Department of Physics, University of Colorado, Boulder, CO 80309, United States of America
| | - S C Burd
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, United States of America
- Department of Physics, University of Colorado, Boulder, CO 80309, United States of America
| | - D Leibfried
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, United States of America
| | - A C Wilson
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, United States of America
| | - D J Wineland
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, United States of America
- Department of Physics, University of Colorado, Boulder, CO 80309, United States of America
- Department of Physics, University of Oregon, Eugene, OR 97403, United States of America
| | - D T C Allcock
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, United States of America
- Department of Physics, University of Colorado, Boulder, CO 80309, United States of America
- Department of Physics, University of Oregon, Eugene, OR 97403, United States of America
| | - D H Slichter
- Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, United States of America
| | - S B Libby
- Physics Division, Physical and Life Sciences, Lawrence Livermore National Laboratory, Livermore, CA 94550, United States of America
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17
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Shankar G, Borkar RM, Udutha S, Kanakaraju M, Charan GS, Misra S, Srinivas R. Identification and structural characterization of the stress degradation products of omeprazole using Q-TOF-LC-ESI-MS/MS and NMR experiments: evaluation of the toxicity of the degradation products. NEW J CHEM 2019. [DOI: 10.1039/c9nj00932a] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Omeprazole (OMP), a prototype proton pump inhibitor used for the treatment of peptic ulcers and gastroesophageal reflux disease (GERD), was subjected to forced degradation studies as per ICH guidelines Q1A (R2).
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Affiliation(s)
- G. Shankar
- Analytical Chemistry
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - Roshan M. Borkar
- Analytical Chemistry
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - Suresh Udutha
- Analytical Chemistry
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - M. Kanakaraju
- Analytical Chemistry
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - G. Sai Charan
- Analytical Chemistry
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - S. Misra
- Biology Division
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - R. Srinivas
- Analytical Chemistry
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
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18
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George A, Villarosa AR, Patterson Norrie T, Hoolsema J, Dahlen HG, Ajwani S, Bhole S, Blinkhorn A, Srinivas R, Yaacoub A, Milat A, Skinner J, Johnson M. Process evaluation of the midwifery initiated oral health-dental service program: perceptions of pregnant women. Aust Dent J 2018; 64:55-65. [PMID: 30375645 DOI: 10.1111/adj.12660] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/23/2018] [Indexed: 02/02/2023]
Abstract
BACKGROUND Pregnant women in Australia seldom seek dental care and are unaware of its importance. To address these gaps the midwifery-initiated oral health dental service (MIOH-DS) program was comprehensive trialled and found effective. The aim of this study was to undertake a process evaluation of the MIOH-DS using the perspectives of pregnant women who participated in the trial. METHODS A qualitative research design was utilized, whereby content analysis was undertaken on data from 11 semi-structured interviews with women who participated in the program. RESULTS All participants were receptive of the MIOH-DS intervention, and found it to be an acceptable intervention that met their needs, and encouraged future positive oral health practices and health-seeking behaviours. They expressed that midwives were an appropriate professional to conduct oral health assessments, education and referrals to affordable dental services. Although some participants were initially apprehensive towards receiving treatment during pregnancy, dental staff members were able to appropriately educate and reassure them during treatment. CONCLUSIONS The MIOH-DS represents a promising and acceptable intervention strategy for pregnant women to promote their oral health. Findings merit further investigation on whether positive outcomes achieved can be sustained when implemented in other national or international settings similar to the study setting.
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Affiliation(s)
- A George
- Centre for Oral Health Outcomes & Research Translation (COHORT), Western Sydney University, South Western Sydney Local Health District, University of Sydney, Liverpool, New South Wales, Australia.,Ingham Institute Applied Medical Research, Translational Health Research Institute, Liverpool, New South Wales, Australia
| | - A R Villarosa
- COHORT, Western Sydney University, South Western Sydney Local Health District, Liverpool, New South Wales, Australia.,Ingham Institute Applied Medical Research, Liverpool, New South Wales, Australia
| | - T Patterson Norrie
- COHORT, Western Sydney University, South Western Sydney Local Health District, Liverpool, New South Wales, Australia.,Ingham Institute Applied Medical Research, Liverpool, New South Wales, Australia
| | - J Hoolsema
- COHORT, Western Sydney University, South Western Sydney Local Health District, Liverpool, New South Wales, Australia.,Ingham Institute Applied Medical Research, Liverpool, New South Wales, Australia
| | - H G Dahlen
- School of Nursing & Midwifery, Ingham Institute Applied Medical Research, Western Sydney University, Parramatta, New South Wales, Australia
| | - S Ajwani
- Sydney Local Health District Oral Health Services, Sydney Dental Hospital, Sydney Research, University of Sydney, Sydney, New South Wales, Australia
| | - S Bhole
- Sydney Local Health District Oral Health Services, Sydney Dental Hospital, Sydney Research, University of Sydney, Sydney, New South Wales, Australia
| | - A Blinkhorn
- Faculty of Dentistry, University of Sydney, Sydney, New South Wales, Australia
| | - R Srinivas
- Centre for Oral Health Outcomes & Research Translation (COHORT), Western Sydney University, South Western Sydney Local Health District, University of Sydney, Liverpool, New South Wales, Australia.,Ingham Institute Applied Medical Research, Translational Health Research Institute, Liverpool, New South Wales, Australia
| | - A Yaacoub
- Nepean Blue Mountains Local Health District Oral Health Services, Penrith, New South Wales, Australia
| | - A Milat
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - J Skinner
- Faculty of Dentistry, University of Sydney, Sydney, New South Wales, Australia
| | - M Johnson
- Ingham Institute Applied Medical Research, Liverpool, New South Wales, Australia.,Faculty of Health Sciences, Australian Catholic University, Sydney, New South Wales, Australia
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19
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Srinivas R, Singh AP, Gupta AA, Kumar P. Holistic approach for quantification and identification of pollutant sources of a river basin by analyzing the open drains using an advanced multivariate clustering. Environ Monit Assess 2018; 190:720. [PMID: 30426281 DOI: 10.1007/s10661-018-7073-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 10/22/2018] [Indexed: 06/09/2023]
Abstract
Global scarcity of freshwater has been gearing towards an unsustainable river basin management and corresponding services to the humans. It needs a holistic approach, which exclusively focuses on effective river water quality monitoring and quantification and identification of pollutant sources, in order to address the issue of sustainability. These days, rivers are heavily contaminated due to the presence of organic and metallic pollutants released from several anthropogenic sources, such as industrial effluents, domestic sewage, and agricultural runoff. It is astonishing to note that even in many developing countries, most of these contaminants are carried through open drains, which enter river premises without proper treatment. Such practice not only devastates riverine ecosystem but also gives rise to deadly diseases, such as minimata and cancer in humans. Considering these issues, the present study develops a novel approach towards simultaneous identification of major sources of pollution in the rivers, along with critical pollutants and locations using an advanced hierarchical cluster and multivariate statistical analysis. A systematic approach has been developed by agglomerating both R-mode and Q-mode analysis, which develops monoplots, two-dimensional biplots, rotated component matrices, and dendrograms (using "SPSS" and "Analyse It" software) to reveal relationships among various quality parameters to identify the pollutant sources along with clustering of critical sampling sites and pollutants. A case study of the Ganges River Basin of India has been considered to demonstrate the efficacy and usefulness of the model by analyzing 85 open drains. Both organic and metallic pollutants are analyzed simultaneously as well as separately to get a holistic understanding of all the relationships and to broaden the perspective of water characterization. Results provide a comprehensive guidance to the policy makers and water managers to optimize corrective efforts, minimize further damage, and improve the water quality condition to ensure sustainable development of the river basin.
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Affiliation(s)
- R Srinivas
- Civil Engineering Department, Birla Institute of Technology and Science, Pilani, 333031, India
| | - Ajit Pratap Singh
- Civil Engineering Department, Birla Institute of Technology and Science, Pilani, 333031, India.
| | - Ayush Aman Gupta
- Civil Engineering Department, Birla Institute of Technology and Science, Pilani, 333031, India
| | - Piyush Kumar
- Civil Engineering Department, Birla Institute of Technology and Science, Pilani, 333031, India
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20
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Purna Chander C, Raju B, Ramesh M, Shankar G, Srinivas R. Liquid chromatography/electrospray ionization tandem mass spectrometry study of repaglinide and its forced degradation products. Rapid Commun Mass Spectrom 2018; 32:1181-1190. [PMID: 29723439 DOI: 10.1002/rcm.8151] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 03/14/2018] [Accepted: 04/22/2018] [Indexed: 06/08/2023]
Abstract
RATIONALE Stress stability studies of drugs have been recognized as an essential part of the drug development process. These studies are used to investigate the intrinsic stability of the drugs and for the development of a selective stability indicating assay method (SIAM). Stress testing is also useful for the formulation and packaging development, shelf-life determination and designing of manufacturing processes. As per regulatory guidelines, stress degradation studies and structural characterization should be carried out to establish degradation pathways of the drug, which is essential from both the efficacy and safety point of view. As the stress stability studies of repaglinide have not been reported in the literature, the present study has been undertaken. METHODS Repaglinide (RP), an oral anti-diabetic drug, was subjected to hydrolysis (acidic, alkaline and neutral), oxidation, photolysis and thermal stress conditions as per International Conference on Harmonization (ICH) guidelines Q1A (R2). The chromatographic separation of the drug and its degradation products (DPs) was achieved on an Agilent XDB C-18 column using the gradient elution method with a mobile phase consisting of 20 mM ammonium acetate and acetonitrile at flow rate of 1.0 mL min-1 . The DPs were characterized using liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) in combination with accurate mass measurements. RESULTS The drug degraded under hydrolytic and oxidative stress, while it was stable under thermal and photolytic stress conditions. In total, six DPs were formed and the LC/MS method described here can resolve all DPs from the parent as well as from each other under various stress conditions. To elucidate the structures of DPs, fragmentation of the [M + H]+ ions of RP and its DPs was studied by using LC/ESI-MS/MS combined with accurate mass measurements. CONCLUSIONS The forced degradation of RP carried out as per ICH guidelines results in the formation of six degradation products which have been characterized using LC/MS/MS in combination with accurate mass measurements.
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Affiliation(s)
- C Purna Chander
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - B Raju
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - M Ramesh
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - G Shankar
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - R Srinivas
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
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Affiliation(s)
- Baira Shandilya Mahamuni
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, Balanagar, Hyderabad, Telangana 500 037, India
| | - R. Srinivas
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, Balanagar, Hyderabad, Telangana 500 037, India
- NCMS, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, Telangana, India
| | - M.V.N Kumar Talluri
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, Balanagar, Hyderabad, Telangana 500 037, India
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22
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Shankar G, Borkar RM, Udutha S, Anagoni SP, Srinivas R. Identification and structural characterization of in vivo metabolites of balofloxacin in rat plasma, urine and feces samples using Q-TOF/LC/ESI/MS/MS : In silico toxicity studies. J Pharm Biomed Anal 2018; 159:200-211. [PMID: 29990887 DOI: 10.1016/j.jpba.2018.06.050] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 06/22/2018] [Accepted: 06/24/2018] [Indexed: 11/30/2022]
Abstract
Balofloxacin is a fluroquinolone antibiotic drug which has been used for the treatment of urinary tract infections (UTIs). Identification and structural characterization of metabolites is a critical component of both drug discovery and drug development research. In vivo metabolites of balofloxacin have been identified and characterized by using liquid chromatography positive ion electrospray ionization high resolution tandem mass spectrometry (LC/ESI-HR-MS/MS) experiments. To identify in vivo metabolites, blood, urine and feces samples were collected after oral administration of the drug to the female Sprague-Dawley rats (n = 3 per group). Protein precipitation, freeze liquid separation followed by solid-phase extraction methods were used for sample preparation. The extracted samples were subjected to LC-ESI/HRMS/MS analysis. The chromatographic separation of the drug and its metabolites were achieved on a XDB, C18 (50, 4.6 mm, 5 mm) column using gradient elution method in combination with 0.1% formic acid and acetonitrile at a flow rate of 0.4 mL/min. A total of 13 phase I and phase II metabolites of balofloxacin have been identified in plasma, urine and feces samples. Most of metabolites were observed in plasma and urine samples including dealkylated, desmethylated, decarbonylated, decarboxylated, hydroxylated, methylated, carboxylated, cysteine conjugated metabolites and high abundance glucuronidated metabolite. The structures of metabolites have been elucidated based on fragmentation patterns, accurate mass measurements and LC/MS/MS experiments. The main phase I metabolites of balofloxacin, decarbonylated, decarboxylated and desmethylated metabolites and phase II methylated metabolite undergo subsequent phase II glucuronidation pathways. In silico toxicity of the drug and its metabolites was determined using ProTox-II. Metabolites B-1, B-2, B-5, B-6, B-7, and B-8 to B-13 were predicted to possess immunotoxicity with high probability score. Additionally, Amine Oxidase A and Prostaglandin G/H Synthase 1 are predicted for metabolites B-1, B-3 to B-6 as toxicity targets with binding probability.
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Affiliation(s)
- G Shankar
- Analytical Department, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - Roshan M Borkar
- Analytical Department, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - Suresh Udutha
- Analytical Department, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - Suresh Pal Anagoni
- Analytical Department, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - R Srinivas
- Analytical Department, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India.
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23
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Yadav K, Rao JL, Srinivas R, Nagaraj R, Jagannadham MV. Characterization of acetylated histidine b 1-ion structure: A competition between oxazolone and side chain imidazole moiety. Eur J Mass Spectrom (Chichester) 2018; 24:261-268. [PMID: 29392979 DOI: 10.1177/1469066718756801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The detection of post-translational modifications of proteins is an important comprehensive research area. Over the years, proteomic studies involving protein acetylation have attracted a great deal of attention. In the present study, we have focussed on the acetylation of histidine and the intrinsic stability of b1-ion of oxazolone ring and/or with side chain imidazole bicyclic product. The formation of oxazolone structure may occur when an amino moiety undergoes acetylation reaction and when it is present in the vicinity of the side chain imidazole moiety. Tryptic peptides generated from the proteins of Acenitobacter radioresistens MMC5-containing N-terminal histidine were explored in a standard proteomic workflow. Formation of [Formula: see text] ion with an oxazolone ring in these peptides has been supported by a tandem mass spectrometric study of a synthetic peptide and density functional theory calculations. The results obtained from this study have implications in understanding the fragmentation of the peptides generated in the proteomic workflows.
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Affiliation(s)
| | - J Laxmikanth Rao
- 1 CSIR-Indian Institute of Chemical Technology, Hyderabad, India
| | - R Srinivas
- 1 CSIR-Indian Institute of Chemical Technology, Hyderabad, India
| | - R Nagaraj
- 2 CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - M V Jagannadham
- 2 CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
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24
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Chavan BB, Vijaya jyothi P, Kalariya PD, Srinivas R, Talluri MVNK. Alcaftadine: Selective Separation and Characterization of Degradation Products by LC–QTOF-MS/MS. Chromatographia 2018. [DOI: 10.1007/s10337-018-3489-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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25
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Baira SM, Kalariya PD, Nimbalkar R, Garg P, Srinivas R, Talluri MVNK. Characterization of forced degradation products of canagliflozine by liquid chromatography/quadrupole time-of-flight tandem mass spectrometry and in silico toxicity predictions. Rapid Commun Mass Spectrom 2018; 32:212-220. [PMID: 29134712 DOI: 10.1002/rcm.8032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 11/07/2017] [Accepted: 11/08/2017] [Indexed: 06/07/2023]
Abstract
RATIONALE Forced degradation studies are useful for better understanding of the stability of active pharmaceutical ingredients and drugs and to generate information about drug degradation pathways and formation of degradation products (DPs). Identification of DPs plays a vital role in establishing the safety and therapeutic benefit of a drug. METHODS Canagliflozin (CAN) was subjected to different stress conditions as per International Conference on Harmonization guidelines (Q1A R2). All the DPs and the drug were well separated on an Aquity CSH C18 (100 × 2.1 mm, 1.7 μm) column using acetonitrile-methanol (70:30, v/v) and formic acid in gradient mode. The same UPLC method was employed for LC/HRMS for the characterization of DPs. In addition, in silico toxicity was predicted for all the DPs by using TOPKAT and DEREK software tools. RESULTS CAN was found to degrade under oxidative stress condition and formed DP1 and DP2. This is a typical case of degradation where co-solvents acetonitrile-water (50:50, v/v) and methanol-water (50:50, v/v) react with CAN under acid hydrolytic conditions leading to the formation of pseudo-DPs, DP3 and DP4, respectively. Among these, DP2 and DP3 showed ocular irritancy whereas DP1 showed skin sensitization. CONCLUSIONS The drug was labile under oxidative stress condition. CAN reacted with co-solvent under acid hydrolytic conditions and gave pseudo-DPs. All the DPs were separated using UPLC and characterized by LC/QTOF/MS/MS. Toxicity of DPs was evaluated using TOPKAT and DEREK software tools.
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Affiliation(s)
- Shandilya Mahamuni Baira
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500 037, Telangana, India
| | - Pradipbhai D Kalariya
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500 037, Telangana, India
| | - Rakesh Nimbalkar
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, S.A.S Nagar, Mohali, Punjab, India
| | - Prabha Garg
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, S.A.S Nagar, Mohali, Punjab, India
| | - R Srinivas
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500 037, Telangana, India
- NCMS, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, Telangana, India
| | - M V N Kumar Talluri
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500 037, Telangana, India
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Srinivas R, Singh AP, Deshmukh A. Development of a HEC-HMS-based watershed modeling system for identification, allocation, and optimization of reservoirs in a river basin. Environ Monit Assess 2017; 190:31. [PMID: 29260336 DOI: 10.1007/s10661-017-6418-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 12/12/2017] [Indexed: 06/07/2023]
Abstract
One of the primary objectives of river basin planning and management is to assess the behavior of the river towards man-made and natural changes. In recent times, the self-purifying capacity of the river is found to be substantially affected because of extensive use of water for agricultural and industrial purposes. Any variation in the flow regime of a river poses a severe impact on the aquatic ecosystem, which affects its self-purifying capacity. Diverting river water for industrial and agricultural uses through dams and barrages reduces the natural flow rate of the river. The present study develops a novel approach by coupling Watershed Modeling System (WMS ver. 10.1) with linear optimization to provide an alternate means of water supply for such users. To explain the effectiveness of the model, a case study on the Ganges river basin of India has been considered. The ecosystem of the Ganges provides such a magnificent biological fabric, that its self-purifying capacity exceeds that of any other river water across the globe. However, the industries found in the river's most polluted stretch consume around 1200 million liters of water every day. In addition, 80% of the river water diverts at Narora barrage for agricultural purposes. As a result, the flow of the river in dry seasons is as less as 300 m3/s. The study suggests the need to develop economically feasible and efficient storage reservoirs to store the rainwater, which can be used to supply industrial and agricultural needs. The WMS software is used to acquire the watershed basin, outlet location, simulated runoff volume, proposed reservoir site, and the hydrograph using the monitored rainfall data of 5 years (2010-2014). The simulated runoff volume is then used to develop an optimization model to determine the required capacity of each reservoir using LINGO software (ver. 16.0). Four different storage reservoirs are proposed in the selected industrial sites of Unnao district, Uttar Pradesh, India. These reservoirs can supply the needs of industries, and thus reducing their dependency on the river Ganges. The model developed herein acts as an effective tool for giving a possible solution to large-scale water supply problems in the river basins, and also guides the decision makers towards restoring the stream flow.
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Affiliation(s)
- R Srinivas
- Birla Institute of Technology and Science, Pilani-Pilani Campus, Pilani, India
| | - Ajit Pratap Singh
- Birla Institute of Technology and Science, Pilani-Pilani Campus, Pilani, India.
| | - Anirban Deshmukh
- Birla Institute of Technology and Science, Pilani-Pilani Campus, Pilani, India
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Chavan BB, Kalariya PD, Tiwari S, Nimbalkar RD, Garg P, Srinivas R, Talluri MVNK. Identification and characterization of vilazodone metabolites in rats and microsomes by ultrahigh-performance liquid chromatography/quadrupole time-of-flight tandem mass spectrometry. Rapid Commun Mass Spectrom 2017; 31:1974-1984. [PMID: 28875544 DOI: 10.1002/rcm.7982] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Revised: 08/30/2017] [Accepted: 08/31/2017] [Indexed: 06/07/2023]
Abstract
RATIONALE Vilazodone is a selective serotonin reuptake inhibitor (SSRI) used for the treatment of major depressive disorder (MDD). An extensive literature search found few reports on the in vivo and in vitro metabolism of vilazodone. Therefore, we report a comprehensive in vivo and in vitro metabolic identification and structural characterization of vilazodone using ultrahigh-performance liquid chromatography/quadrupole time-of-flight tandem mass spectrometry (UPLC/Q-TOF/MS/MS) and in silico toxicity study of the metabolites. METHODS To identify in vivo metabolites of vilazodone, blood, urine and faeces samples were collected at different time intervals starting from 0 h to 48 h after oral administration of vilazodone to Sprague-Dawley rats. The in vitro metabolism study was conducted with human liver microsomes (HLM) and rat liver microsomes (RLM). The samples were prepared using an optimized sample preparation approach involving protein precipitation followed by solid-phase extraction. The metabolites have been identified and characterized by using LC/ESI-MS/MS. RESULTS A total of 12 metabolites (M1-M12) were identified in in vivo and in vitro matrices and characterized by LC/ESI-MS/MS. The majority of the metabolites were observed in urine, while a few metabolites were present in faeces and plasma. Two metabolites were observed in the in vitro study. A semi-quantitative study based on percentage counts shows that metabolites M11, M6 and M8 were observed in higher amounts in urine, faeces and plasma, respectively. CONCLUSIONS The structures of all the 12 metabolites were elucidated by using LC/ESI-MS/MS. The study suggests that vilazodone was metabolized via hydroxylation, dihydroxylation, glucuronidation, oxidative deamination, dealkylation, dehydrogenation and dioxidation. All the metabolites were screened for toxicity using an in silico tool.
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Affiliation(s)
- Balasaheb B Chavan
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
| | - Pradipbhai D Kalariya
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
| | - Shristy Tiwari
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
| | - Rakesh D Nimbalkar
- National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S., Nagar, 160 062, Punjab, India
| | - Prabha Garg
- National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S., Nagar, 160 062, Punjab, India
| | - R Srinivas
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
- National Center for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad, 500 607, India
| | - M V N Kumar Talluri
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
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Ramprakash S, Agarwal RK, Dhanya R, Sedai A, Kumari A, Parmar L, Srinivas R, Kakulamari VR, Marwah P, Soni R, Williams S, Rathnayake W, Sen S, Tulpule S, Faulkner L. Rejection of paternal vs maternal fully matched bone marrow grafts in children with thalassemia. Bone Marrow Transplant 2017; 52:1585-1586. [PMID: 28920948 PMCID: PMC5671933 DOI: 10.1038/bmt.2017.199] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- S Ramprakash
- Bone Marrow Transplant Unit, People Tree Hospitals, Bangalore, India
| | | | - R Dhanya
- Sankalp India Foundation, Bangalore, India
| | - A Sedai
- Sankalp India Foundation, Bangalore, India
| | - A Kumari
- Sankalp India Foundation, Bangalore, India
| | - L Parmar
- Sankalp India Foundation, Bangalore, India
| | - R Srinivas
- Sankalp India Foundation, Bangalore, India
| | | | - P Marwah
- Bone Marrow Transplant Unit, South East Asia Institute for Thalassemia, Jaipur, India
| | - R Soni
- Bone Marrow Transplant Unit, South East Asia Institute for Thalassemia, Jaipur, India
| | - S Williams
- Bone Marrow Transplant Unit, Nawaloka Hospital, Colombo, Sri Lanka
| | - W Rathnayake
- Bone Marrow Transplant Unit, Nawaloka Hospital, Colombo, Sri Lanka
| | - S Sen
- Bone Marrow Transplant Unit, Kokilaben Dhirubhai Ambani Hospital, Mumbai, India
| | - S Tulpule
- Bone Marrow Transplant Unit, Kokilaben Dhirubhai Ambani Hospital, Mumbai, India
| | - L Faulkner
- Cure2Children Foundation, Florence, Italy
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Shankar G, Borkar RM, Suresh U, Guntuku L, Naidu VGM, Nagesh N, Srinivas R. Forced degradation studies of lansoprazole using LC-ESI HRMS and 1 H-NMR experiments: in vitro toxicity evaluation of major degradation products. J Mass Spectrom 2017; 52:459-471. [PMID: 28544042 DOI: 10.1002/jms.3949] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 05/12/2017] [Accepted: 05/15/2017] [Indexed: 06/07/2023]
Abstract
Regulatory agencies from all over the world have set up stringent guidelines with regard to drug degradation products due to their toxic effects or carcinogenicity. Lansoprazole, a proton-pump inhibitor, was subjected to forced degradation studies as per ICH guidelines Q1A (R2). The drug was found to degrade under acidic, basic, neutral hydrolysis and oxidative stress conditions, whereas it was found to be stable under thermal and photolytic conditions. The chromatographic separation of the drug and its degradation products were achieved on a Hiber Purospher, C18 (250 × 4.6 mm, 5 μ) column using 10 mM ammonium acetate and acetonitrile as a mobile phase in a gradient elution mode at a flow rate of 1.0 ml/min. The eight degradation products (DP1-8) were identified and characterized by UPLC/ESI/HRMS with in-source CID experiments combined with accurate mass measurements. DP-1, DP-2 and DP-3 were formed in acidic, DP-4 in basic, DP-5 in neutral and DP-1, DP-6, DP-7 and DP-8 were in oxidation stress condition Among eight degradation products, five were hitherto unknown degradation products. In addition, one of the major degradation products, DP-2, was isolated by using semi preparative HPLC and other two, DP-6 and DP-7 were synthesized. The cytotoxic effect of these degradation products (DP-2, DP-6 and DP-7) were tested on normal human cells such as HEK 293 (embryonic kidney cells) and RWPE-1(normal prostate epithelial cells) by MTT assay. From the results of cytotoxicity, it was found that lansoprazole as well as its degradation products (DP-2, DP-6 and DP-7) were nontoxic up to 50-μM concentrations, and the latter showed slightly higher cytotoxicity when compared with that of lansoprazole. DNA binding studies using spectroscopic techniques indicate that DP-2, DP-6 and DP-7 molecules interact with ctDNA and may bind to its surface. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- G Shankar
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad, 500 007, India
| | - R M Borkar
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad, 500 007, India
| | - U Suresh
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad, 500 007, India
| | - L Guntuku
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500037, India
| | - V G M Naidu
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500037, India
| | - N Nagesh
- CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Tarnaka, Hyderabad, 500007, India
| | - R Srinivas
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad, 500 007, India
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Thummar M, Patel PN, Petkar AL, Swain D, Srinivas R, Samanthula G. Identification of degradation products of saquinavir mesylate by ultra-high-performance liquid chromatography/electrospray ionization quadrupole time-of-flight tandem mass spectrometry and its application to quality control. Rapid Commun Mass Spectrom 2017; 31:771-781. [PMID: 28233930 DOI: 10.1002/rcm.7842] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 02/20/2017] [Accepted: 02/21/2017] [Indexed: 06/06/2023]
Abstract
RATIONALE Saquinavir mesylate (SQM) is an antiviral drug used for the treatment of HIV infections. The identification and characterization of all degradation products are essential for achieving the quality in pharmaceutical product development and also for patient safety. METHODS The drug was subjected to hydrolytic (HCl, NaOH and water), oxidative (H2 O2 ), photolytic (UV and fluorescence light) and thermal (dry heat) forced degradation conditions as per ICH guidelines. The best chromatographic separation of the drug and all degradation products (DPs) was achieved on a CSH-Phenyl Hexyl column (100 × 2.1 mm, 1.7 μm) with ammonium acetate (10 mM, pH 5.0) and methanol as mobile phase in gradient mode at a flow rate of 0.28 mL/min. RESULTS Nine DPs were obtained under various forced degradation conditions. All the DPs were characterized by using ultra-high-performance liquid chromatography/electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UHPLC/ESI-QTOF MS/MS) and the degradation pathway of the drug was justified by mechanistic explanations. The main DPs were formed by amide hydrolysis, conversion into diastereomers, an N-oxide and dehydration as well as oxidation of the alcohol from the drug. The method was validated and can be used in a quality control (QC) laboratory to assure the quality of SQM in bulk and finished formulations. CONCLUSIONS A simple UHPLC/photodiode array (PDA) method was developed and successfully transferred to UHPLC/ESI-Q-TOF MS/MS for the identification and characterization of DPs. Very interestingly, diastereomeric DPs were obtained and successfully resolved by the chromatographic method. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Mohit Thummar
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research (NIPER), Balanagar, Hyderabad, 500037, Telangana, India
| | - Prinesh N Patel
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research (NIPER), Balanagar, Hyderabad, 500037, Telangana, India
| | - Arun L Petkar
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research (NIPER), Balanagar, Hyderabad, 500037, Telangana, India
| | - Debasish Swain
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research (NIPER), Balanagar, Hyderabad, 500037, Telangana, India
| | - R Srinivas
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research (NIPER), Balanagar, Hyderabad, 500037, Telangana, India
- National Centre for Mass Spectrometry, CSIR - Indian Institute of Chemical Technology, Hyderabad, 500 007, Telangana, India
| | - Gananadhamu Samanthula
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research (NIPER), Balanagar, Hyderabad, 500037, Telangana, India
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Chavan BB, Kalariya PD, Nimbalkar RD, Garg P, Srinivas R, Kumar Talluri MVN. Identification and characterization of fluvastatin metabolites in rats by UHPLC/Q-TOF/MS/MS and in silico toxicological screening of the metabolites. J Mass Spectrom 2017; 52:296-314. [PMID: 28295913 DOI: 10.1002/jms.3929] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 03/07/2017] [Accepted: 03/08/2017] [Indexed: 06/06/2023]
Abstract
The present study reports the in vivo and in vitro identification and characterization of metabolites of fluvastatin, the 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitor, using liquid chromatography-mass spectrometry (LC-MS). In vitro studies were conducted by incubating the drug with human liver microsomes and rat liver microsomes. In vivo studies were carried out by administration of the drug in the form of suspension to the Sprague-Dawley rats followed by collection of urine, faeces and blood at different time points up to 24 h. Further, samples were prepared by optimized sample preparation method, which includes freeze liquid extraction, protein precipitation and solid phase extraction. The extracted and concentrated samples were analysed using ultrahigh-performance liquid chromatography-quadruple time-of-flight tandem mass spectrometry. A total of 15 metabolites were observed in urine, which includes hydroxyl, sulphated, desisopropyl, dehydrogenated, dehydroxylated and glucuronide metabolites. A few of the metabolites were also present in faeces and plasma samples. In in vitro studies, a few metabolites were observed that were also present in in vivo samples. All the metabolites were characterized using ultrahigh-performance liquid chromatography-quadruple time-of-flight tandem mass spectrometry in combination with accurate mass measurement. Finally, in silico toxicity studies indicated that some of the metabolites show or possess carcinogenicity and skin sensitization. Several metabolites that were identified in rats are proposed to have toxicological significance on the basis of in silico evaluation. However, these metabolites are of no human relevance. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Balasaheb B Chavan
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
| | - Pradipbhai D Kalariya
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
| | - Rakesh D Nimbalkar
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, Punjab, 160 062, India
| | - Prabha Garg
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, Punjab, 160 062, India
| | - R Srinivas
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
- National Center for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad, 500607, India
| | - M V N Kumar Talluri
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
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Ramesh Babu A, Raju G, Purna Chander C, Bhandi MM, Ananth Reddy M, Niladari Raju MV, Jayathirtha Rao V, Bhanuprakash K, Srinivas R. Differentiation of isomeric para- and meta-substituted 2,5-diphenyl-1,3,4-oxadiazole derivatives of anthracene by electrospray ionization tandem mass spectrometry. Rapid Commun Mass Spectrom 2017; 31:469-474. [PMID: 27957771 DOI: 10.1002/rcm.7805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 11/30/2016] [Accepted: 12/08/2016] [Indexed: 06/06/2023]
Affiliation(s)
- A Ramesh Babu
- National Centre for Mass Spectrometry, CSIR - Indian Institute of Chemical Technology, Hyderabad, 500007, India
| | - G Raju
- National Centre for Mass Spectrometry, CSIR - Indian Institute of Chemical Technology, Hyderabad, 500007, India
| | - C Purna Chander
- National Centre for Mass Spectrometry, CSIR - Indian Institute of Chemical Technology, Hyderabad, 500007, India
| | - Murali Mohan Bhandi
- National Centre for Mass Spectrometry, CSIR - Indian Institute of Chemical Technology, Hyderabad, 500007, India
| | - M Ananth Reddy
- Organic Chemistry Division (II), CSIR - Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - M V Niladari Raju
- Organic Chemistry Division (II), CSIR - Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - V Jayathirtha Rao
- Organic Chemistry Division (II), CSIR - Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - K Bhanuprakash
- Inorganic and Physical Chemistry Division, CSIR - Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - R Srinivas
- National Centre for Mass Spectrometry, CSIR - Indian Institute of Chemical Technology, Hyderabad, 500007, India
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Vishnuvardhan C, Saibaba B, Allakonda L, Swain D, Gananadhamu S, Srinivas R, Satheeshkumar N. LC–ESI–MS/MS evaluation of forced degradation behaviour of silodosin: In vitro anti cancer activity evaluation of silodosin and major degradation products. J Pharm Biomed Anal 2017; 134:1-10. [DOI: 10.1016/j.jpba.2016.11.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 10/23/2016] [Accepted: 11/09/2016] [Indexed: 12/15/2022]
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Khatua TN, Borkar RM, Mohammed SA, Dinda AK, Srinivas R, Banerjee SK. Novel Sulfur Metabolites of Garlic Attenuate Cardiac Hypertrophy and Remodeling through Induction of Na +/K +-ATPase Expression. Front Pharmacol 2017; 8:18. [PMID: 28194108 PMCID: PMC5276815 DOI: 10.3389/fphar.2017.00018] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 01/10/2017] [Indexed: 11/13/2022] Open
Abstract
Epidemiologic studies show an inverse correlation between garlic consumption and progression of cardiovascular disease. However, the molecular basis for the beneficial effect of garlic on the heart is not known. Therefore, the objective of the present study was to (1) investigate the effect of raw garlic on isoproterenol (Iso) induced cardiac hypertrophy (2) find the active metabolites of garlic responsible for the beneficial effect. Cardiac hypertrophy was induced in rats by subcutaneous single injection of Iso 5 mg kg-1 day-1 for 15 days and the effect of garlic (250 mg/kg/day orally) was evaluated. Garlic metabolites in in vivo were identified by LC/MS study. The effect of garlic and its metabolites were evaluated against hypertrophy in H9C2 cells. Garlic normalized cardiac oxidative stress after Iso administration. Cardiac pathology and mitochondrial enzyme activities were improved in hypertrophy heart after garlic administration. Decreased Na+/K+-ATPase protein level that observed in hypertrophy heart was increased after garlic administration. We identified three garlic metabolites in rat serum. To confirm the role of garlic metabolites on cardiac hypertrophy, Na+/K+-ATPase expression and intracellular calcium levels were measured after treating H9C2 cells with raw garlic and two of its active metabolites, allyl methyl sulfide and allyl methyl sulfoxide. Raw garlic and both metabolites increased Na+/K+-ATPase protein level and decreased intracellular calcium levels and cell size in Iso treated H9C2 cells. This antihypertrophic effect of garlic and its sulfur metabolites were lost in H9C2 cells in presence of Na+/K+-ATPase inhibitor. In conclusion, garlic and its active metabolites increased Na+/K+-ATPase in rat heart, and attenuated cardiac hypertrophy and associated remodeling. Our data suggest that identified new garlic metabolites may be useful for therapeutic intervention against cardiac hypertrophy.
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Affiliation(s)
- Tarak N Khatua
- Division of Medicinal Chemistry and Pharmacology, Indian Institute of Chemical TechnologyHyderabad, India; Drug Discovery Research Center, Translational Health Science and Technology InstituteFaridabad, India
| | - Roshan M Borkar
- National Centre for Mass Spectrometry, Indian Institute of Chemical Technology Hyderabad, India
| | - Soheb A Mohammed
- Drug Discovery Research Center, Translational Health Science and Technology Institute Faridabad, India
| | - Amit K Dinda
- Department of Pathology, All India Institute of Medical Sciences New Delhi, India
| | - R Srinivas
- National Centre for Mass Spectrometry, Indian Institute of Chemical Technology Hyderabad, India
| | - Sanjay K Banerjee
- Division of Medicinal Chemistry and Pharmacology, Indian Institute of Chemical TechnologyHyderabad, India; Drug Discovery Research Center, Translational Health Science and Technology InstituteFaridabad, India
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Patel PN, Kalariya PD, Thummar M, Gananadhamu S, Srinivas R. In vivo
metabolite identification of acotiamide in rats using ultra-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry. Biomed Chromatogr 2017; 31. [DOI: 10.1002/bmc.3915] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 12/04/2016] [Accepted: 12/06/2016] [Indexed: 11/09/2022]
Affiliation(s)
- Prinesh N. Patel
- Department of Pharmaceutical Analysis; National Institute of Pharmaceutical Education and Research; Hyderabad Telangana India
| | - Pradipbhai D. Kalariya
- Department of Pharmaceutical Analysis; National Institute of Pharmaceutical Education and Research; Hyderabad Telangana India
| | - Mohit Thummar
- Department of Pharmaceutical Analysis; National Institute of Pharmaceutical Education and Research; Hyderabad Telangana India
| | - S. Gananadhamu
- Department of Pharmaceutical Analysis; National Institute of Pharmaceutical Education and Research; Hyderabad Telangana India
| | - R. Srinivas
- Department of Pharmaceutical Analysis; National Institute of Pharmaceutical Education and Research; Hyderabad Telangana India
- National Centre for Mass Spectrometry; CSIR-Indian Institute of Chemical Technology; Hyderabad Telangana India
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Devrukhakar PS, Shiva Shankar M, Shankar G, Srinivas R. A stability-indicating LC-MS/MS method for zidovudine: Identification, characterization and toxicity prediction of two major acid degradation products. J Pharm Anal 2017; 7:231-236. [PMID: 29404043 PMCID: PMC5790685 DOI: 10.1016/j.jpha.2017.01.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 01/10/2017] [Accepted: 01/17/2017] [Indexed: 12/04/2022] Open
Abstract
Zidvovudine (AZT) is a nucleoside analogue reverse transcriptase inhibitor (NRTI), a class of anti-retroviral drug. A stability-indicating assay method for AZT was developed in line with ICH guideline. Successful separation of AZT and its degradation products was achieved by gradient elution mode on reverse phase C18 column using 10 mM ammonium acetate: acetonitrile as the mobile phase at 0.8 mL/min flow rate, 25 µL injection volume, 30 °C column temperature and 285 nm detection wavelength. Two major acid degradation products were identified and characterized by liquid chromatography–electrospray ionization mass spectrometry (LC–ESI/MS/MS) and accurate mass measurements. The probable mechanisms for the formation of degradation products were identified based on a comparison of the fragmentation pattern of the [M + H] + ions of AZT and its degradation products. One of the degradation products, DP-1, was isolated by semi-preparative high performance liquid chromatography (HPLC) using Waters XBridge Prep C18 (250 mm×10 mm, 5 µm). Degradation products showed higher toxicity compared to the drug in some models assessed by TOPKAT software. The method validation was performed with respect to robustness, specificity, linearity, precision and accuracy as per ICH guideline Q2 (R1).
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Affiliation(s)
- Prashant S Devrukhakar
- School of Advance Sciences, Vellore Institute of technology (VIT), Katpadi, Vellore, Tamil Nadu 632014, India
| | - M Shiva Shankar
- School of Advance Sciences, Vellore Institute of technology (VIT), Katpadi, Vellore, Tamil Nadu 632014, India
| | - G Shankar
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India
| | - R Srinivas
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India
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Baira SM, Srinivasulu G, Nimbalkar R, Garg P, Srinivas R, Talluri MVNK. Characterization of degradation products of regorafenib by LC-QTOF-MS and NMR spectroscopy: investigation of rearrangement and odd-electron ion formation during collision-induced dissociations under ESI-MS/MS. NEW J CHEM 2017. [DOI: 10.1039/c7nj01440f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Characterization of degradation products of regorafenib by LC-QTOF-MS and NMR.
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Affiliation(s)
- Shandilya Mahamuni Baira
- Department of Pharmaceutical Analysis
- National Institute of Pharmaceutical Education & Research
- Hyderabad
- India
| | - Gannoju Srinivasulu
- Department of Pharmaceutical Analysis
- National Institute of Pharmaceutical Education & Research
- Hyderabad
- India
| | - Rakesh Nimbalkar
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education & Research
- Mohali
- India
| | - Prabha Garg
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education & Research
- Mohali
- India
| | - R. Srinivas
- Department of Pharmaceutical Analysis
- National Institute of Pharmaceutical Education & Research
- Hyderabad
- India
- NCMS, CSIR-Indian Institute of Chemical Technology
| | - M. V. N. Kumar Talluri
- Department of Pharmaceutical Analysis
- National Institute of Pharmaceutical Education & Research
- Hyderabad
- India
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Kalariya PD, Namdev D, Srinivas R, Gananadhamu S. Application of experimental design and response surface technique for selecting the optimum RP-HPLC conditions for the determination of moxifloxacin HCl and ketorolac tromethamine in eye drops. Journal of Saudi Chemical Society 2017. [DOI: 10.1016/j.jscs.2014.04.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Vishnuvardhan C, Baikadi S, Borkar RM, Srinivas R, Satheeshkumar N. In vivo metabolic investigation of silodosin using UHPLC-QTOF-MS/MS and in silico toxicological screening of its metabolites. J Mass Spectrom 2016; 51:867-882. [PMID: 27747994 DOI: 10.1002/jms.3795] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 05/19/2016] [Accepted: 05/29/2016] [Indexed: 06/06/2023]
Abstract
Silodosin (SLD) is a novel α1-adrenoceptor antagonist which has shown promising clinical efficacy and safety in patients with benign prostatic hyperplasia (BPH). However, lack of information about metabolism of SLD prompted us to investigate metabolic fate of SLD in rats. To identify in vivo metabolites of SLD, urine, feces and plasma were collected from Sprague-Dawley rats after its oral administration. The samples were prepared using an optimized sample preparation approach involving protein precipitation followed by solid-phase extraction and then subjected to LC/HR-MS/MS analysis. A total of 13 phase I and six phase II metabolites of SLD have been identified in rat urine which includes hydroxylated, N-dealkylated, dehydrogenated, oxidative, glucosylated, glucuronide and N-sulphated metabolites, which are also observed in feces. In plasma, only dehydrogenated, N-dealkylated and unchanged SLD are observed. The structure elucidation of metabolites was done by fragmentation in MS/MS in combination with HRMS data. The potential toxicity profile of SLD and its metabolites were predicted using TOPKAT software and most of the metabolites were proposed to show a certain degree of skin sensitization and occular irritancy. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Chiguru Vishnuvardhan
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Hyderabad (NIPER-H), Balanagar, Hyderabad, 500037, Telangana, India
| | - Saibaba Baikadi
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Hyderabad (NIPER-H), Balanagar, Hyderabad, 500037, Telangana, India
| | - Roshan M Borkar
- National Center for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad, 500607, Telangana, India
| | - R Srinivas
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Hyderabad (NIPER-H), Balanagar, Hyderabad, 500037, Telangana, India.
- National Center for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad, 500607, Telangana, India.
| | - N Satheeshkumar
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Hyderabad (NIPER-H), Balanagar, Hyderabad, 500037, Telangana, India.
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Vishnuvardhan C, Swain D, Borkar R, Gananadhamu S, Srinivas R, Satheeshkumar N. Study of Forced Degradation Behaviour of Brinzolamide Using LC–ESI–Q-TOF and In Silico Toxicity Prediction. Chromatographia 2016. [DOI: 10.1007/s10337-016-3149-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Borkar RM, Bhandi MM, Dubey AP, Ganga Reddy V, Komirishetty P, Nandekar PP, Sangamwar AT, Kamal A, Banerjee SK, Srinivas R. An evaluation of the CYP2D6 and CYP3A4 inhibition potential of metoprolol metabolites and their contribution to drug-drug and drug-herb interaction by LC-ESI/MS/MS. Biomed Chromatogr 2016; 30:1556-72. [PMID: 27006091 DOI: 10.1002/bmc.3721] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Revised: 03/08/2016] [Accepted: 03/11/2016] [Indexed: 11/06/2022]
Abstract
The aim of the present study was to evaluate the contribution of metabolites to drug-drug interaction and drug-herb interaction using the inhibition of CYP2D6 and CYP3A4 by metoprolol (MET) and its metabolites. The peak concentrations of unbound plasma concentration of MET, α-hydroxy metoprolol (HM), O-desmethyl metoprolol (ODM) and N-desisopropyl metoprolol (DIM) were 90.37 ± 2.69, 33.32 ± 1.92, 16.93 ± 1.70 and 7.96 ± 0.94 ng/mL, respectively. The metabolites identified, HM and ODM, had a ratio of metabolic area under the concentration-time curve (AUC) to parent AUC of ≥0.25 when either total or unbound concentration of metabolite was considered. In vitro CYP2D6 and CYP3A4 inhibition by MET, HM and ODM study revealed that MET, HM and ODM were not inhibitors of CYP3A4-catalyzed midazolam metabolism and CYP2D6-catalyzed dextromethorphan metabolism. However, DIM only met the criteria of >10% of the total drug related material and <25% of the parent using unbound concentrations. If CYP inhibition testing is solely based on metabolite exposure, DIM metabolite would probably not be considered. However, the present study has demonstrated that DIM contributes significantly to in vitro drug-drug interaction. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Roshan M Borkar
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India.,Medicinal Chemistry and Pharmacology Division, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - Murali Mohan Bhandi
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - Ajay P Dubey
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500037, India
| | - V Ganga Reddy
- Medicinal Chemistry and Pharmacology Division, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - Prashanth Komirishetty
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500037, India
| | - Prajwal P Nandekar
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Sector 67, S.A.S. Nagar (Mohali), 160 062, Punjab, India
| | - Abhay T Sangamwar
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Sector 67, S.A.S. Nagar (Mohali), 160 062, Punjab, India
| | - Ahmed Kamal
- Medicinal Chemistry and Pharmacology Division, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - Sanjay K Banerjee
- Medicinal Chemistry and Pharmacology Division, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India.,Drug Discovery Research Center, Translational Health Science and Technology Institute, Faridabad, 121001, India
| | - R Srinivas
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India.,Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500037, India
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Nandekar PP, Khomane K, Chaudhary V, Rathod VP, Borkar RM, Bhandi MM, Srinivas R, Sangamwar AT, Guchhait SK, Bansal AK. Identification of leads for antiproliferative activity on MDA-MB-435 human breast cancer cells through pharmacophore and CYP1A1-mediated metabolism. Eur J Med Chem 2016; 115:82-93. [PMID: 26994845 DOI: 10.1016/j.ejmech.2016.02.061] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 02/21/2016] [Accepted: 02/24/2016] [Indexed: 12/26/2022]
Abstract
CYP1A1 is a potential target for anticancer drug development due to its overexpression in certain cancer cells and role in cancer progression. To identify new leads for CYP1A1 mediated anticancer action, we attempted ligand based pharmacophore mapping, virtual screening of databases, molecular docking, MetaSite based filtering, and molecular dynamics simulations. Initial computational and in vitro screening identified 11 compounds from which we identified two lead compounds, ZINC33468944 and ZINC32101539, showed potential antitumor activity on MDA-MB-435 cell lines (GI50 < 0.1 μM) and CYP1A1 inhibition of 0.13 and 0.3 μM, respectively. Furthermore, the lead compounds were evaluated for CYP1A1 mediated metabolism, showing N-hydroxylated metabolites, which have potential of DNA adduct formation and cause cancerous cell death. Analysis of molecular dynamics simulations provided important guidelines for the further modification of the lead compounds. Hence, we claim the lead molecules for further development in anticancer drug discovery.
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Affiliation(s)
- Prajwal P Nandekar
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Punjab, India
| | - Kailas Khomane
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Punjab, India
| | - Vikas Chaudhary
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Punjab, India
| | - Vijay P Rathod
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Punjab, India
| | - Roshan M Borkar
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology (IICT), Hyderabad, India
| | - Murali Mohan Bhandi
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology (IICT), Hyderabad, India
| | - R Srinivas
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology (IICT), Hyderabad, India
| | - Abhay T Sangamwar
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Punjab, India.
| | - Sankar K Guchhait
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Punjab, India
| | - Arvind K Bansal
- Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Punjab, India
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Ramesh Babu A, Raju G, Purna Chander C, Shoban Babu B, Srinivas R, Sharma GVM. Electrospray ionization tandem mass spectrometric study of protonated and alkali- cationized α/ε-hybrid peptides: differentiation of a pair of dipeptide positional isomers. Eur J Mass Spectrom (Chichester) 2016; 22:181-191. [PMID: 27882883 DOI: 10.1255/ejms.1431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A new class of Boc-N-protected hybrid peptides derived from L- Ala and ε6-Caa (L-Ala = L-Alanine, Caa = C-linked carboamino acid derived from D-xylose) have been studied by positive ion electrospray ionization (ESI) ion-trap tandem mass spectrometry (MS/MS). MSn spectra of protonated and alkali-cationized hybrid peptides produce characteristic fragmentation involving the peptide backbone, the tert-butyloxycarbonyl (Boc) group, and the side chain. The dipeptide positional isomers are differentiated by the collision-induced dissociation (CID) of the protonated and alkali-cationized peptides. The CID of [M + H]+ ion of Boc-NH-L-Ala-ε-Caa- OCH3 (1) shows a prominent [M + H - C4H8]+ ion, which is totally absent for its positional isomer Boc-NH-ε-Caa-L-Ala-OCH3 (6), which instead shows significant loss of t-butanol. The formation of the [M + Cat - C4H8]+ ion is totally absent and [M + Cat - Boc + H]+ is prominent in the CID of the [M + Cat]+ ion of Boc-NH-L-Ala-ε-Caa- OCH3 (1), whereas the former is highly abundant and the latter is of low abundance for its positional isomer Boc-NH-ε-Caa-L-Ala-OCH3 (6). It is observed that 'b' ions are abundant when oxazolone structures are formed through a five-membered cyclic transition state in tetra-, penta-, and hexapeptides and the cyclization process for larger 'b' ions led to an insignificant abundance. However, the significant 'b' ion is formed in ε,α-dipeptide, which may have a seven-membered substituted 2-oxoazepanium ion structure. The MSn spectra of [M + Cat - Boc + H]+ ions of these peptides are found to be significantly different to those of [M + H - Boc + H]+ ions. The CID spectra of [M + Cat - Boc + H]+ ions of peptide acids containing L-Ala at the C-terminus show an abundant N-terminal rearrangement ion, [bn + 17 + Cat]+, which is absent for the peptide acids containing ε-Caa at the C-terminus. Thus, the results of these hybrid peptides provide sequencing information, the structure of the cyclic intermediate involved in the formation of the rearrangement ion, and distinguish a pair of dipeptide positional isomers.
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Affiliation(s)
- A Ramesh Babu
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India
| | - G Raju
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India
| | - C Purna Chander
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India
| | - B Shoban Babu
- Organic and Biomolecular Chemistry Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India
| | - R Srinivas
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India.
| | - G V M Sharma
- Organic and Biomolecular Chemistry Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India.
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44
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Bhandi MM, Borkar RM, Shankar G, Raut S, Nagesh N, Srinivas R. Identification and characterization of stressed degradation products of rabeprazole using LC-ESI/MS/MS and 1H-NMR experiments: in vitro toxicity evaluation of major degradation products. RSC Adv 2016. [DOI: 10.1039/c5ra27965h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Rabeprazole, an antiulcer drug in the class of proton pump inhibitors was subjected to force degradation studies as per ICH guidelines Q1A (R2).
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Affiliation(s)
- Murali Mohan Bhandi
- National Centre for Mass Spectrometry
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - Roshan M. Borkar
- National Centre for Mass Spectrometry
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | - G. Shankar
- National Centre for Mass Spectrometry
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
| | | | - Narayana Nagesh
- CSIR-Centre for Cellular and Molecular Biology
- Hyderabad 500007
- India
| | - R. Srinivas
- National Centre for Mass Spectrometry
- CSIR-Indian Institute of Chemical Technology
- Hyderabad
- India
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45
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Patel PN, Kalariya PD, Gananadhamu S, Srinivas R. Forced degradation of fingolimod: Effect of co-solvent and characterization of degradation products by UHPLC-Q-TOF–MS/MS and 1H NMR. J Pharm Biomed Anal 2015; 115:388-94. [DOI: 10.1016/j.jpba.2015.07.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 07/12/2015] [Accepted: 07/22/2015] [Indexed: 10/23/2022]
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46
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Kalariya PD, Patel PN, Kavya P, Sharma M, Garg P, Srinivas R, Talluri MVNK. Rapid structural characterization of in vivo and in vitro metabolites of tinoridine using UHPLC-QTOF-MS/MS and in silico toxicological screening of its metabolites. J Mass Spectrom 2015; 50:1222-33. [PMID: 26505767 DOI: 10.1002/jms.3640] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 08/04/2015] [Accepted: 08/04/2015] [Indexed: 05/28/2023]
Abstract
Tinoridine is a nonsteroidal anti-inflammatory drug and also has potent radical scavenger and antiperoxidative activity. However, metabolism of tinoridine has not been thoroughly investigated. To identify in vivo metabolites, the drug was administered to Sprague-Dawley rats (n = 5) at a dose of 20 mg kg(-1), and blood, urine and feces were collected at different time points up to 24 h. In vitro metabolism was delved by incubating the drug with rat liver microsomes and human liver microsomes. The metabolites were enriched by optimized sample preparation involving protein precipitation using acetonitrile, followed by solid-phase extraction. Data processes were carried out using multiple mass defects filters to eliminate false-positive ions. A total of 11 metabolites have been identified in urine samples including hydroxyl, dealkylated, acetylated and glucuronide metabolites; among them, some were also observed in plasma and feces samples. Only two major metabolites were formed using liver microsomal incubations. These metabolites were also observed in vivo. All the 11 metabolites, which are hitherto unknown and novel, were characterized by using ultrahigh-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry in combination with accurate mass measurements. Finally, in silico toxicological screening of all metabolites was evaluated, and two metabolites were proposed to show a certain degree of lung or liver toxicity.
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MESH Headings
- Administration, Oral
- Animals
- Anti-Inflammatory Agents, Non-Steroidal/analysis
- Anti-Inflammatory Agents, Non-Steroidal/metabolism
- Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics
- Anti-Inflammatory Agents, Non-Steroidal/toxicity
- Chromatography, High Pressure Liquid/methods
- Computer Simulation
- Feces
- Female
- Humans
- Male
- Mice
- Microsomes, Liver/drug effects
- Microsomes, Liver/metabolism
- Molecular Structure
- Rats, Sprague-Dawley
- Software
- Solid Phase Extraction
- Spectrometry, Mass, Electrospray Ionization/methods
- Tandem Mass Spectrometry/methods
- Thienopyridines/analysis
- Thienopyridines/metabolism
- Thienopyridines/pharmacokinetics
- Thienopyridines/toxicity
- Toxicity Tests/methods
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Affiliation(s)
- Pradipbhai D Kalariya
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
| | - Prinesh N Patel
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
| | - P Kavya
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
| | - Mahesh Sharma
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), Sector-67, S.A.S (Mohali), Nagar, Punjab, 160062, India
| | - Prabha Garg
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research (NIPER), Sector-67, S.A.S (Mohali), Nagar, Punjab, 160062, India
| | - R Srinivas
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education & Research, IDPL R&D Campus, Balanagar, Hyderabad, 500 037, India
- National Center for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad, 500607, India
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Shantikumar S, Satheeshkumar N, Srinivas R. Pharmacokinetic and protein binding profile of peptidomimetic DPP-4 inhibitor - Teneligliptin in rats using liquid chromatography-tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2015; 1002:194-200. [PMID: 26340762 DOI: 10.1016/j.jchromb.2015.08.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 08/13/2015] [Accepted: 08/17/2015] [Indexed: 12/15/2022]
Abstract
The aim of the present study is to explore pharmacokinetic and protein binding characteristics of a novel dipeptidylpeptidase-4 (DPP-4) inhibitor, teneligliptin in rats using an ultra high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS). It is required for demonstrating the high protein binding nature of teneligliptin which can be extended for drug repositioning to brain disorders. Sample preparation was accomplished through a protein precipitation procedure using acetonitrile. Separation of teneligliptin and sitagliptin (IS) from endogenous components with high selectivity and sensitivity (0.5ng/mL) was achieved within 4min using Poroshell 120 EC-C18 column (100×3.0mm, 2.7μ). A gradient mobile phase consisting of 10mM ammonium formate and acetonitrile was applied at a flow rate of 0.45mL/min. Detection of target ions [M+H](+) at m/z 427.2274 for teneligliptin and m/z 408.1258 for IS was performed in selective ion mode using positive ion electrospray ionization high resolution accurate mass spectrometry. The linearity of the method was found to be in the range of 0.5-1000ng/mL. The matrix effect was 88.7-94.5% for teneligliptin. Plasma samples were found to stable under different storage conditions. It was successfully applied to pharmacokinetic and plasma protein binding study of drug in rats. Results showed linear dose proportionality of pharmacokinetics at 0.1 and 1mg/kg and relatively high protein binding of teneligliptin (85.46 ± 0.24 %) compared with other DPP-4 inhibitors.
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Affiliation(s)
- S Shantikumar
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Hyderabad (NIPER-H), Balanagar, Hyderabad 500037, Telangana, India
| | - N Satheeshkumar
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Hyderabad (NIPER-H), Balanagar, Hyderabad 500037, Telangana, India.
| | - R Srinivas
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Hyderabad (NIPER-H), Balanagar, Hyderabad 500037, Telangana, India; National Center for Mass Spectrometry, Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500607,Telangana, India
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48
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Patel PN, Kalariya PD, Swamy CV, Gananadhamu S, Srinivas R. Quantitation of acotiamide in rat plasma by UHPLC-Q-TOF-MS: method development, validation and application to pharmacokinetics. Biomed Chromatogr 2015; 30:363-8. [DOI: 10.1002/bmc.3555] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 06/19/2015] [Accepted: 07/02/2015] [Indexed: 01/11/2023]
Affiliation(s)
- Prinesh N. Patel
- Department of Pharmaceutical Analysis; National Institute of Pharmaceutical Education and Research; Balanagar Hyderabad 500037 Telangana India
| | - Pradipbhai D. Kalariya
- Department of Pharmaceutical Analysis; National Institute of Pharmaceutical Education and Research; Balanagar Hyderabad 500037 Telangana India
| | - Challa Veerabhadra Swamy
- Department of Pharmacology; National Institute of Pharmaceutical Education and Research; Balanagar Hyderabad 500037 Telangana India
| | - S. Gananadhamu
- Department of Pharmaceutical Analysis; National Institute of Pharmaceutical Education and Research; Balanagar Hyderabad 500037 Telangana India
| | - R. Srinivas
- Department of Pharmaceutical Analysis; National Institute of Pharmaceutical Education and Research; Balanagar Hyderabad 500037 Telangana India
- National Centre for Mass Spectrometry; CSIR - Indian Institute of Chemical Technology; Hyderabad 500 007 Telangana India
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49
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Patel PN, Kalariya PD, Sharma M, Garg P, Talluri MVNK, Gananadhamu S, Srinivas R. Characterization of forced degradation products of pazopanib hydrochloride by UHPLC-Q-TOF/MS and in silico toxicity prediction. J Mass Spectrom 2015; 50:918-928. [PMID: 26349647 DOI: 10.1002/jms.3602] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 03/23/2015] [Accepted: 04/02/2015] [Indexed: 06/05/2023]
Abstract
Pazopanib (PZ), an anti-cancer drug, was subjected to forced degradation under hydrolytic (acid, base and neutral), oxidative, photolytic and thermal stress conditions as per International Conference on Harmonization guidelines. A selective stability indicating validated method was developed using a Waters Acquity UPLC HSS T3 (100 × 2.1 mm, 1.7 µm) column in gradient mode with ammonium acetate buffer (10 mM, pH 5.0) and acetonitrile. PZ was found to degrade only in photolytic conditions to produce six transformation products (TPs). All the TPs were identified and characterized by liquid chromatography/atmospheric pressure chemical ionization-quadrupole-time of flight mass spectrometry experiments in combination with accurate mass measurements. Plausible mechanisms have been proposed for the formation of TPs. In silico toxicity was predicted using TOPKAT and DEREK softwares for all the TPs. The TP, N4-(2,3-dimethyl-2H-indazol-6-yl)-N4-methylpyrimidine-2,4-diamine, was found to be genotoxic, whereas all other TPs with sulfonamide moiety were hepatotoxic. The data reported here are expected to be of significance as this study foresees the formation of one potential genotoxic and five hepatotoxic degradation/transformation products.
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Affiliation(s)
- Prinesh N Patel
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500037, Telangana, India
| | - Pradipbhai D Kalariya
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500037, Telangana, India
| | - Mahesh Sharma
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Sector 67, SAS Nagar (Mohali), Punjab, 160062, India
| | - Prabha Garg
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Sector 67, SAS Nagar (Mohali), Punjab, 160062, India
| | - M V N Kumar Talluri
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500037, Telangana, India
| | - S Gananadhamu
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500037, Telangana, India
| | - R Srinivas
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research, Balanagar, Hyderabad, 500037, Telangana, India
- National Center for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, Telangana, India
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Naresh Chary V, Sudarshana Reddy B, Kumar CD, Srinivas R, Prabhakar S. Characterization of N,N-dimethyl amino acids by electrospray ionization-tandem mass spectrometry. J Mass Spectrom 2015; 50:771-781. [PMID: 26259661 DOI: 10.1002/jms.3588] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 02/23/2015] [Accepted: 02/23/2015] [Indexed: 06/04/2023]
Abstract
Methylation is an essential metabolic process for a number of critical reactions in the body. Methyl groups are involved in the healthy function of the body life processes, by conducting methylation process involving specific enzymes. In these processes, various amino acids are methylated, and the occurrence of methylated amino acids in nature is diverse. Nowadays, mass-spectrometric-based identification of small molecules as biomarkers for diseases is a growing research. Although all dimethyl amino acids are metabolically important molecules, mass spectral data are available only for a few of them in the literature. In this study, we report synthesis and characterization of all dimethyl amino acids, by electrospray ionization-tandem mass spectrometry (MS/MS) experiments on protonated molecules. The MS/MS spectra of all the studied dimethyl amino acids showed preliminary loss of H2O + CO to form corresponding immonium ions. The other product ions in the spectra are highly characteristic of the methyl groups on the nitrogen and side chain of the amino acids. The amino acids, which are isomeric and isobaric with the studied dimethyl amino acids, gave distinctive MS/MS spectra. The study also included MS/MS analysis of immonium ions of dimethyl amino acids that provide information on side chain structure, and it is further tested to determine the N-terminal amino acid of the peptides.
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Affiliation(s)
- V Naresh Chary
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, Telangana, India
| | - B Sudarshana Reddy
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, Telangana, India
- Academy of Scientific and Innovative Research, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, Telangana, India
| | - Ch Dinesh Kumar
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, Telangana, India
| | - R Srinivas
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, Telangana, India
| | - S Prabhakar
- National Centre for Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, Telangana, India
- Academy of Scientific and Innovative Research, CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, Telangana, India
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