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Kang Z, Xue M, Miao H, Wang W, Ding X, Yin MM, Hu YJ. Structure-activity relationship between gold nanoclusters and human serum albumin: Effects of ligand isomerization. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 320:124598. [PMID: 38850819 DOI: 10.1016/j.saa.2024.124598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 05/08/2024] [Accepted: 06/03/2024] [Indexed: 06/10/2024]
Abstract
The interactions between gold nanoclusters (AuNCs) and proteins have been extensively investigated. Nevertheless, the structure-activity relationship between gold nanoclusters and proteins in terms of ligand isomerization remained unclear. Here, interactions between Au25NCs modified with para-, inter- and ortho-mercaptobenzoic acid (p/m/o-MBA-Au25NCs) and human serum albumin (HSA) were analyzed. The results of the multispectral approach showed that all three gold nanoclusters bound to the site I in dynamic modes to increase the stability of HSA. There were significant differences in the binding intensity, thermodynamic parameters, main driving forces, and binding ratios between these three gold nanoclusters and HSA, which might be related to the existence forms of the three ligands on the surface of AuNCs. Due to the different polarities of AuNCs themselves, the impact of three AuNCs on the microenvironment of amino acid residues in HSA was also different. It could be seen that ligand isomerization significantly affected the interactions between gold nanoclusters and proteins. This work will provide theoretical guidance for ligand selection and biological applications of metal nanoclusters.
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Affiliation(s)
- Zhuo Kang
- Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi 435002, PR China
| | - Meng Xue
- Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi 435002, PR China
| | - Hu Miao
- Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi 435002, PR China
| | - Wen Wang
- Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi 435002, PR China
| | - Xin Ding
- Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi 435002, PR China
| | - Miao-Miao Yin
- Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi 435002, PR China.
| | - Yan-Jun Hu
- Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, College of Chemistry and Chemical Engineering, Hubei Normal University, Huangshi 435002, PR China.
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2
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Jain A, Yadav VK, Kumari A, Saha SK, Metre RK, Bhattacharyya S, Rana NK. Supported-amine-catalyzed cascade synthesis of spiro-thiazolone-tetrahydrothiophenes: assessing HSA binding activity. Org Biomol Chem 2024; 22:5087-5092. [PMID: 38835316 DOI: 10.1039/d4ob00619d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
We have devised a supported-amine-catalyzed efficient synthesis of spiro-thiazolone-tetrahydrothiophenes via a sulfa-Michael/aldol cascade approach. The catalyst demonstrated sustained efficacy over 21 cycles. These derivatives were found to exhibit excellent binding abilities with purified human serum albumin as indicated by both in silico and in vitro-based experiments.
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Affiliation(s)
- Anshul Jain
- Department of Chemistry, Indian Institute of Technology Jodhpur, Rajasthan-342030, India.
| | - Vinay K Yadav
- Department of Bioscience and Bioengineering, Indian Institute of Technology Jodhpur, Rajasthan-342030, India
| | - Akanksha Kumari
- Department of Chemistry, Indian Institute of Technology Jodhpur, Rajasthan-342030, India.
| | - Suman K Saha
- Department of Chemistry, Indian Institute of Technology Jodhpur, Rajasthan-342030, India.
| | - Ramesh K Metre
- Department of Chemistry, Indian Institute of Technology Jodhpur, Rajasthan-342030, India.
| | - Sudipta Bhattacharyya
- Department of Bioscience and Bioengineering, Indian Institute of Technology Jodhpur, Rajasthan-342030, India
| | - Nirmal K Rana
- Department of Chemistry, Indian Institute of Technology Jodhpur, Rajasthan-342030, India.
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Banerjee S, Kistwal T, Sajeevan A, Datta A. Release of Warfarin from Human Serum Albumin by Water‐soluble CdSe Nanotetrapods. Chemphyschem 2020; 21:2709-2714. [DOI: 10.1002/cphc.202000292] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 09/27/2020] [Indexed: 01/03/2023]
Affiliation(s)
- Sucheta Banerjee
- Department of Chemistry Indian Institute of Technology Bombay Powai, Mumbai 400 076 India
| | - Tanuja Kistwal
- Department of Chemistry Indian Institute of Technology Bombay Powai, Mumbai 400 076 India
| | - Amritha Sajeevan
- Department of Chemical Sciences Indian Institute of Science Education and Research Kolkata Campus Rd Mohanpur, West Bengal 741246 India
| | - Anindya Datta
- Department of Chemistry Indian Institute of Technology Bombay Powai, Mumbai 400 076 India
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5
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Bratty MA. Spectroscopic and molecular docking studies for characterizing binding mechanism and conformational changes of human serum albumin upon interaction with Telmisartan. Saudi Pharm J 2020; 28:729-736. [PMID: 32550805 PMCID: PMC7292872 DOI: 10.1016/j.jsps.2020.04.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 04/28/2020] [Indexed: 11/28/2022] Open
Abstract
Human serum albumin (HSA), one of the most copious plasma proteins is responsible for binding and transportation of many exogenous and endogenous ligands including drugs. In this study, we intended to explore the extent and types of binding interaction present between HSA and the antihypertensive drug, telmisartan (TLM). The conformational changes in HSA due to this binding were also studied using different spectroscopic and molecular docking techniques. The spectral shifting and intensity variations upon interaction with TLM were studied using FT-IR spectroscopy. Binding constant and the change in absorption of HSA at its λmax was analyzed using absorption spectroscopy. Eventually, the types and extent of binding interactions were confirmed using molecular docking technique. Results have shown that TLM significantly interacts with the binding site-1 of HSA utilizing strong hydrogen bonding with Glu292, and Lys195 residues. The UV-absorption intensities were found to be decreased serially as the drug concentration increased with a binding constant of 1.01 × 103 M−1. The secondary structure analysis using FT-IR spectroscopy also revealed a marked reduction in the α-helix (56%) component of HSA on interaction. This study gives critical insights into the interaction of TLM with HSA protein which eventually affects the concentration of TLM reaching the site of action and ultimately its therapeutic profile.
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Key Words
- ADME, Absorption, Distribution, Metabolism, Excretion
- Binding
- FT-IR
- Glu, Glutamate
- HAS, Human Serum Albumin
- Human serum albumin
- Lys, Lysine
- Molecular Docking
- PDB, Protein Data Bank
- TLM, Telmisartan
- Telmisartan
- UCSF, University of California, San Fransisco
- UV–Vis
- λmax, wavelength of maximum absorbance
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Affiliation(s)
- Mohammed Al Bratty
- Department of Pharmaceutical Chemistry, College of Pharmacy, Jazan University, P. Box No. 114, Jazan, Saudi Arabia
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6
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Andrýsková P, Šišková KM, Michetschlägerová Š, Jiráková K, Kubala M, Jirák D. The Effect of Fatty Acids and BSA Purity on Synthesis and Properties of Fluorescent Gold Nanoclusters. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E343. [PMID: 32079332 PMCID: PMC7075172 DOI: 10.3390/nano10020343] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 01/31/2020] [Accepted: 02/09/2020] [Indexed: 12/25/2022]
Abstract
Fluorescent gold nanoclusters (AuNCs) are envisaged as a novel type of fluorophores. This work reports on the first comparative study investigating the effect of presence/absence/abundance of fatty acids (namely palmitic acid, PA) or other substances (like glycoproteins and globulins) in the protein (bovine serum albumin, BSA) on synthesis and properties of the final AuNCs. The most popular template (BSA) and microwave (MW)-assisted synthesis of AuNCs have been intentionally chosen. Our results clearly demonstrate that the fluorescent characteristics (i.e., fluorescence lifetime and quantum yield) are affected by the fatty acids and/or other substances. Importantly, the as-prepared AuNCs are biocompatible, as determined by Alamar Blue assay performed on Hep G2 cell line.
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Affiliation(s)
- Pavlína Andrýsková
- Department of Biophysics, Faculty of Science, Palacký University Olomouc, 17. Listopadu 12, 771 46 Olomouc, Czech Republic;
| | - Karolína Machalová Šišková
- Department of Biophysics, Faculty of Science, Palacký University Olomouc, 17. Listopadu 12, 771 46 Olomouc, Czech Republic;
| | - Šárka Michetschlägerová
- Department of Science and Research, Faculty of Health Studies, Technical University of Liberec, Studentska 1402/2, 461 17 Liberec, Czech Republic; (Š.M.); (K.J.); (D.J.)
| | - Klára Jiráková
- Department of Science and Research, Faculty of Health Studies, Technical University of Liberec, Studentska 1402/2, 461 17 Liberec, Czech Republic; (Š.M.); (K.J.); (D.J.)
| | - Martin Kubala
- Department of Experimental Physics, Faculty of Science, Palacký University Olomouc, 17. Listopadu 12, 771 46 Olomouc, Czech Republic;
| | - Daniel Jirák
- Department of Science and Research, Faculty of Health Studies, Technical University of Liberec, Studentska 1402/2, 461 17 Liberec, Czech Republic; (Š.M.); (K.J.); (D.J.)
- Institute for Clinical and Experimental Medicine, Videnska 9, 140 21 Prague, Czech Republic
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Zuber G, Weiss E, Chiper M. Biocompatible gold nanoclusters: synthetic strategies and biomedical prospects. NANOTECHNOLOGY 2019; 30:352001. [PMID: 31071693 DOI: 10.1088/1361-6528/ab2088] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The latest advances concerning ultra-small gold nanoparticles (≤2 nm) commonly known as gold nanoclusters (AuNCs) are reviewed and discussed in the context of biological and biomedical applications (labeling, delivery, imaging and therapy). A great diversity of synthetic methods has been developed and optimized aiming to improve the chemical structures and physicochemical properties of the resulting AuNCs. The main synthetic approaches were surveyed with emphasis on methods leading to water-soluble AuNCs since aqueous solutions are the preferred media for biological applications. The most representative and recent experimental results are discussed in relationship to their potential for biomedical applications.
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Affiliation(s)
- Guy Zuber
- Molecular and Pharmaceutical Engineering of Biologics, CNRS-Université de Strasbourg UMR 7242, Boulevard Sebastien Brant, F-67412, Illkirch, France
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Lysozyme encapsulated gold nanoclusters for probing the early stage of lysozyme aggregation under acidic conditions. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2019; 197:111540. [DOI: 10.1016/j.jphotobiol.2019.111540] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 06/02/2019] [Accepted: 06/21/2019] [Indexed: 12/22/2022]
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Mukherjee S, Ganorkar K, Kumar A, Sehra N, Ghosh SK. Switching of Trp-214 intrinsic rotamer population in human serum albumin: An insight into the aftermath of embracing therapeutic bioorganic luminophore azapodophyllotoxin into sudlow site I. Bioorg Chem 2019; 84:63-75. [DOI: 10.1016/j.bioorg.2018.11.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/02/2018] [Accepted: 11/13/2018] [Indexed: 01/14/2023]
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Russell BA, Kubiak-Ossowska K, Chen Y, Mulheran PA. Critical role of tyrosine-20 in formation of gold nanoclusters within lysozyme: a molecular dynamics study. Phys Chem Chem Phys 2019; 21:4907-4911. [PMID: 30756100 DOI: 10.1039/c8cp06374e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Lysozyme is one of the most commonly used proteins for encapsulating gold nanoclusters, yielding Ly-AuNC complexes. While possible applications of Ly-AuNCs in environmental, biological and trace metal sensing in solution have been demonstrated, there is currently a poor understanding of the physical characteristics of the Ly-AuNC complex. In this study we have employed fully atomistic molecular dynamics simulations to gain an understanding of the formation of Au clusters within the protein. It was found that in order to form AuNCs in the simulations, an approach of targeted insertion of Au atoms at a critical surface residue was needed. Tyrosine is known to be crucial for the reduction of Au salts experimentally, and our simulations showed that Tyr20 is the key residue for the formation of an AuNC beneath the protein surface in the α-helical domain. It is hoped these observations will aid future improvements and modification of Ly-AuNCs via alterations of the alpha-helix domain or Tyr20.
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Affiliation(s)
- Ben A Russell
- Department of Physics, University of Strathclyde, John Anderson Building, 107 Rottenrow, Glasgow, G4 0NG, UK.
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Alkudaisi N, Russell BA, Jachimska B, Birch DJS, Chen Y. Detecting lysozyme unfolding via the fluorescence of lysozyme encapsulated gold nanoclusters. J Mater Chem B 2019; 7:1167-1175. [PMID: 32254785 DOI: 10.1039/c9tb00009g] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Protein misfolding plays a critical role in the manifestation of amyloidosis type diseases. Therefore, understanding protein unfolding and the ability to track protein unfolding in a dynamic manner are of considerable interest. Fluorescence-based techniques are powerful tools for gaining real-time information about the local environmental conditions of a probe on the nanoscale. Fluorescent gold nanoclusters (AuNCs) are a new type of fluorescent probes which are <2 nm in diameter, incredibly robust and offer highly sensitive, wavelength tuneable emission. Their small size minimises intrusion and makes AuNCs ideal for studying protein dynamics. Lysozyme has previously been used to encapsulate AuNCs. The unfolding dynamics of lysozyme under different environmental conditions have been well-studied and being an amyloid type protein makes lysozyme an ideal candidate for encapsulating AuNCs in order to test their sensitivity to protein unfolding. In this study, we tracked the fluorescence characteristics of AuNCs encapsulated in lysozyme while inducing protein unfolding using urea, sodium dodecyl sulphate (SDS) and elevated temperature and compared them to complimentary circular dichroism spectra. It is found that AuNC fluorescence emission is quenched upon induced protein unfolding either due to a decrease in Forster Resonance Energy Transfer (FRET) efficiency between tryptophan and AuNCs or solvent exposure of the AuNC. Fluorescence lifetime measurements confirmed quenching to be collisional via oxygen dissolved in a solution which increases as the AuNC was exposed to the solvent during unfolding. Moreover, the longer decay component τ1 was observed to decrease as the protein unfolded, due to the increased collisional quenching. It is suggested that AuNC sensitivity to solvent exposure might be utilised in the future as a new approach to studying and possibly even detecting amyloidosis type diseases.
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Affiliation(s)
- Nora Alkudaisi
- Department of Physics, SUPA, University of Strathclyde, John Anderson Building, 107 Rottenrow, Glasgow G4 0NG, UK.
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12
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Xu YJ, Su MM, Li HL, Liu QX, Xu C, Yang YS, Zhu HL. A fluorescent sensor for discrimination of HSA from BSA through selectivity evolution. Anal Chim Acta 2018; 1043:123-131. [DOI: 10.1016/j.aca.2018.09.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 09/03/2018] [Accepted: 09/05/2018] [Indexed: 01/20/2023]
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13
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Narwal M, Kumar D, Mukherjee TK, Bhattacharyya R, Banerjee D. Molecular dynamics simulation as a tool for assessment of drug binding property of human serum albumin. Mol Biol Rep 2018; 45:1647-1652. [DOI: 10.1007/s11033-018-4308-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 08/10/2018] [Indexed: 12/30/2022]
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Russell BA, Jachimska B, Chen Y. Polyallylamine hydrochloride coating enhances the fluorescence emission of Human Serum Albumin encapsulated gold nanoclusters. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2018; 187:131-135. [PMID: 30145463 DOI: 10.1016/j.jphotobiol.2018.08.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 08/10/2018] [Accepted: 08/15/2018] [Indexed: 11/28/2022]
Abstract
Protein encapsulated gold nanoclusters have received much attention due to the possibility of using them as a non-toxic fluorescent probe or marker for biomedical applications, however one major disadvantage currently is their low brightness and quantum yield in comparison to currently used fluorescent markers. A method of increasing the fluorescence emission of Human Serum Albumin (HSA) encapsulated gold nanoclusters (AuNCs) via a Polyallylamide hydrochloride (PAH) coating is described. PAH molecules with a molecular weight of ~17,500 Da were found to enhance the fluorescence emission of HSA-AuNCs by 3-fold when the protein/polymer concentration ratio is 2:1 in solution. Interestingly, the fluorescence lifetime of the AuNCs was found to decrease while the native tryptophan (TRP) fluorescence lifetime also decreased during the fluorescence emission intensity enhancement caused by the PAH binding. Coinciding with the decrease in fluorescence lifetime, the zeta potential of the system was observed to be zero during maximum fluorescence intensity enhancement, causing the formation of large aggregates. These results suggest that PAH binds to the HSA-AuNCs acting as a linker; causing aggregation and rigidification, which results in a decrease in separation between native TRP of HSA and AuNCs; improving Förster Resonance Energy Transfer (FRET) and increasing the fluorescence emission intensity. These findings are critical to the development of brighter protein encapsulated AuNCs.
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Affiliation(s)
- Ben Allan Russell
- Department of Physics, University of Strathclyde, Glasgow G4 0NG, United Kingdom.
| | - Barbara Jachimska
- Jerzy Haber Institute of Catalysis and Surface Chemistry Polish Academy of Sciences, Krakow PL-30329, Poland
| | - Yu Chen
- Department of Physics, University of Strathclyde, Glasgow G4 0NG, United Kingdom
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Russell BA, Garton A, Alshammari AS, Birch DJS, Chen Y. Sudlow site II of human serum albumin remains functional after gold nanocluster encapsulation: a fluorescence-based drug binding study of L-Dopa. Methods Appl Fluoresc 2018; 6:035017. [PMID: 29924742 DOI: 10.1088/2050-6120/aacdee] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Fluorescent protein-encapsulated gold nanoclusters (AuNCs) offer a non-toxic means of sensing and imaging biological phenomena on the nanoscale. However, the biofunctionality of proteins encapsulating AuNCs has not been fully elucidated to date. Here we studied the biofunctionality of the second major drug binding site (Sudlow II) of Human Serum Albumin (HSA) encapsulated AuNCs after AuNC synthesis. L-Dopa, a fluorescent drug molecule associated with the clinical treatment of Parkinson's disease, which commonly binds to the Sudlow II site, was used to study the availability of the site before and after AuNC synthesis through changes to its fluorescence characteristics. L-Dopa was observed using its intrinsic fluorescence to readily bind to HSA-AuNCs complexes. Interestingly, the fluorescence emission intensity of AuNCs linearly increased with L-Dopa concentration while exciting the AuNC directly at 470 nm, Using a 400 nM HSA-AuNC solution, L-Dopa was rapidly detected at a limit of 300 pM, indicating that HSA-AuNCs fluorescence is extremely sensitive to molecular binding at the Sudlow II binding site. Future research may be able to utilize this sensitivity to improve the fluorescence characteristics of AuNCs within HSA-AuNCs for imaging and sensing including drug binding studies.
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Affiliation(s)
- Ben A Russell
- Photophysics Group, Department of Physics, SUPA, University of Strathclyde, John Anderson Building, 107 Rottenrow, Glasgow, G4 0NG, United Kingdom
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Russell BA, Jachimska B, Komorek P, Mulheran PA, Chen Y. Lysozyme encapsulated gold nanoclusters: effects of cluster synthesis on natural protein characteristics. Phys Chem Chem Phys 2018; 19:7228-7235. [PMID: 28234394 DOI: 10.1039/c7cp00540g] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The study of gold nanoclusters (AuNCs) has seen much interest in recent history due to their unique fluorescence properties and environmentally friendly synthesis method using proteins as a growth scaffold. The differences in the physicochemical properties of lysozyme encapsulated AuNCs in comparison to natural lysozyme are characterised in order to determine the effects AuNCs have on natural protein behaviour. The hydrodynamic radius (dynamic light scattering), light absorbance (UV-Vis), electrophoretic mobility, relative density, dynamic viscosity, adsorption (quartz crystal microbalance) and circular dichroism (CD) characteristics of the molecules were studied. It was found that lysozyme forms small dimer/trimer aggregates upon the synthesis of AuNCs within the protein. The diameter of Ly-AuNCs was found to be 8.0 nm across a pH range of 2-11 indicating dimer formation, but larger aggregates with diameters >20 nm were formed between pH 3 and 6. The formation of larger aggregates limits the use of Ly-AuNCs as a fluorescent probe in this pH range. A large shift in the protein's isoelectric point was also observed, shifting from 11.0 to 4.0 upon AuNC synthesis. This resulted in major changes to the adsorption characteristics of lysozyme, observed using a QCM. A monolayer of 8 nm was seen for Ly-AuNCs at pH 4, offering further evidence that the proteins form small aggregates, unlike the natural monomer form of lysozyme. The adsorption of Ly-AuNCs was seen to decrease as pH was increased; this is in major contrast to the lysozyme adsorption behaviour. A decrease in the α-helix content was observed from 25% in natural lysozyme to 1% in Ly-AuNCs. This coincided with an increase in the β-sheet content after AuNC synthesis indicating that the natural structure of lysozyme was lost. The formation of protein dimers, the change in the protein surface charge from positive to negative, and secondary structure alteration caused by the AuNC synthesis must be considered before attempting to utilise Ly-AuNCs as in vivo probes.
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Affiliation(s)
- B A Russell
- Department of Physics, Strathclyde University, John Anderson Building, 107 Rottenrow, Glasgow G4 0NG, UK.
| | - B Jachimska
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30-239 Cracow, Poland
| | - P Komorek
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30-239 Cracow, Poland and Faculty of Physics, Astronomy and Applied Computer Science, Jagellonian University, Stanislawa Lojasiewicza, 30-348 Cracow, Poland
| | - P A Mulheran
- Department of Chemical and Process Engineering, Strathclyde University, Glasgow G1 1XJ, UK
| | - Y Chen
- Department of Physics, Strathclyde University, John Anderson Building, 107 Rottenrow, Glasgow G4 0NG, UK.
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Russell BA, Jachimska B, Kralka I, Mulheran PA, Chen Y. Human serum albumin encapsulated gold nanoclusters: effects of cluster synthesis on natural protein characteristics. J Mater Chem B 2016; 4:6876-6882. [DOI: 10.1039/c6tb01827k] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The differences in the physiochemical properties between native Human Serum Albumin (HSA) and HSA encapsulated gold nanoclusters (HSA-AuNCs) are characterised.
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Affiliation(s)
- B. A. Russell
- Department of Physics
- Strathclyde University
- Glasgow G4 0NG
- UK
| | - B. Jachimska
- Jerzy Haber Institute of Catalysis and Surface Chemistry
- Polish Academy of Sciences
- 30-239 Cracow
- Poland
| | - I. Kralka
- Jerzy Haber Institute of Catalysis and Surface Chemistry
- Polish Academy of Sciences
- 30-239 Cracow
- Poland
| | - P. A. Mulheran
- Department of Chemical and Process Engineering
- Strathclyde University
- Glasgow G1 1XJ
- UK
| | - Y. Chen
- Department of Physics
- Strathclyde University
- Glasgow G4 0NG
- UK
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