1
|
Drachman N, Lepoitevin M, Szapary H, Wiener B, Maulbetsch W, Stein D. Nanopore ion sources deliver individual ions of amino acids and peptides directly into high vacuum. Nat Commun 2024; 15:7709. [PMID: 39231934 PMCID: PMC11375035 DOI: 10.1038/s41467-024-51455-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 08/07/2024] [Indexed: 09/06/2024] Open
Abstract
Electrospray ionization is widely used to generate vapor phase ions for analysis by mass spectrometry in proteomics research. However, only a small fraction of the analyte enters the mass spectrometer due to losses that are fundamentally linked to the use of a background gas to stimulate the generation of ions from electrosprayed droplets. Here we report a nanopore ion source that delivers ions directly into high vacuum from aqueous solutions. The ion source comprises a pulled quartz pipette with a sub-100 nm opening. Ions escape an electrified meniscus by ion evaporation and travel along collisionless trajectories to the ion detector. We measure mass spectra of 16 different amino acid ions, post-translationally modified variants of glutathione, and the peptide angiotensin II, showing that these analytes can be emitted as desolvated ions. The emitted current is composed of ions rather than charged droplets, and more than 90% of the current can be recovered in a distant collector.
Collapse
Affiliation(s)
| | | | - Hannah Szapary
- Physics Department, Brown University, Providence, RI, USA
| | | | | | - Derek Stein
- Physics Department, Brown University, Providence, RI, USA.
- School of Engineering, Brown University, Providence, RI, USA.
| |
Collapse
|
2
|
Wells SS, Bain IJ, Valenta AC, Lenhart AE, Steyer DJ, Kennedy RT. Microdialysis coupled with droplet microfluidics and mass spectrometry for determination of neurotransmitters in vivo with high temporal resolution. Analyst 2024; 149:2328-2337. [PMID: 38488040 PMCID: PMC11018092 DOI: 10.1039/d4an00112e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 03/10/2024] [Indexed: 04/16/2024]
Abstract
Monitoring the concentration fluctuations of neurotransmitters in vivo is valuable for elucidating the chemical signals that underlie brain functions. Microdialysis sampling is a widely used tool for monitoring neurochemicals in vivo. The volume requirements of most techniques that have been coupled to microdialysis, such as HPLC, result in fraction collection times of minutes, thus limiting the temporal resolution possible. Further the time of analysis can become long for cases where many fractions are collected. Previously we have used direct analysis of dialysate by low-flow electrospray ionization-tandem mass spectrometry (ESI-MS/MS) on a triple quadrupole mass spectrometer to monitor acetylcholine, glutamate, and γ-amino-butyric acid to achieve multiplexed in vivo monitoring with temporal resolution of seconds. Here, we have expanded this approach to adenosine, dopamine, and serotonin. The method achieved limits of detection down to 2 nM, enabling basal concentrations of all these compounds, except serotonin, to be measured in vivo. Comparative analysis with LC-MS/MS showed accurate results for all compounds except for glutamate, possibly due to interference for this compound in vivo. Pairing this analysis with droplet microfluidics yields 11 s temporal resolution and can generate dialysate fractions down to 3 nL at rates up to 3 fractions per s from a microdialysis probe. The system is applied to multiplexed monitoring of neurotransmitter dynamics in response to stimulation by 100 mM K+ and amphetamine. These applications demonstrate the suitability of the droplet ESI-MS/MS method for monitoring short-term dynamics of up to six neurotransmitters simultaneously.
Collapse
Affiliation(s)
- Shane S Wells
- Department of Chemistry, University of Michigan, 930 N. University Ave, Ann Arbor, MI 48109-1055, USA.
| | - Ian J Bain
- Department of Chemistry, University of Michigan, 930 N. University Ave, Ann Arbor, MI 48109-1055, USA.
| | - Alec C Valenta
- Department of Chemistry, University of Michigan, 930 N. University Ave, Ann Arbor, MI 48109-1055, USA.
| | - Ashley E Lenhart
- Department of Chemistry, University of Michigan, 930 N. University Ave, Ann Arbor, MI 48109-1055, USA.
| | - Daniel J Steyer
- Department of Chemistry, University of Michigan, 930 N. University Ave, Ann Arbor, MI 48109-1055, USA.
| | - Robert T Kennedy
- Department of Chemistry, University of Michigan, 930 N. University Ave, Ann Arbor, MI 48109-1055, USA.
| |
Collapse
|
3
|
Chua ZQ, Prabhu GRD, Wang YW, Raju CM, Buchowiecki K, Ochirov O, Elpa DP, Urban PL. Moderate Signal Enhancement in Electrospray Ionization Mass Spectrometry by Focusing Electrospray Plume with a Dielectric Layer around the Mass Spectrometer's Orifice. Molecules 2024; 29:316. [PMID: 38257229 PMCID: PMC10821223 DOI: 10.3390/molecules29020316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 12/22/2023] [Accepted: 01/03/2024] [Indexed: 01/24/2024] Open
Abstract
Electrospray ionization (ESI) is among the commonly used atmospheric pressure ionization techniques in mass spectrometry (MS). One of the drawbacks of ESI is the formation of divergent plumes composed of polydisperse microdroplets, which lead to low transmission efficiency. Here, we propose a new method to potentially improve the transmission efficiency of ESI, which does not require additional electrical components and complex interface modification. A dielectric plate-made of ceramic-was used in place of a regular metallic sampling cone. Due to the charge accumulation on the dielectric surface, the dielectric layer around the MS orifice distorts the electric field, focusing the charged electrospray cloud towards the MS inlet. The concept was first verified using charge measurement on the dielectric material surface and computational simulation; then, online experiments were carried out to demonstrate the potential of this method in MS applications. In the online experiment, signal enhancements were observed for dielectric plates with different geometries, distances of the electrospray needle axis from the MS inlet, and various compounds. For example, in the case of acetaminophen (15 μM), the signal enhancement was up to 1.82 times (plate B) using the default distance of the electrospray needle axis from the MS inlet (d = 1.5 mm) and 12.18 times (plate C) using a longer distance (d = 7 mm).
Collapse
Affiliation(s)
- Zi Qing Chua
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan (Y.-W.W.); (C.M.R.); (K.B.); (O.O.); (D.P.E.)
| | - Gurpur Rakesh D. Prabhu
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan (Y.-W.W.); (C.M.R.); (K.B.); (O.O.); (D.P.E.)
| | - Yi-Wun Wang
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan (Y.-W.W.); (C.M.R.); (K.B.); (O.O.); (D.P.E.)
| | - Chamarthi Maheswar Raju
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan (Y.-W.W.); (C.M.R.); (K.B.); (O.O.); (D.P.E.)
| | - Krzysztof Buchowiecki
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan (Y.-W.W.); (C.M.R.); (K.B.); (O.O.); (D.P.E.)
| | - Ochir Ochirov
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan (Y.-W.W.); (C.M.R.); (K.B.); (O.O.); (D.P.E.)
| | - Decibel P. Elpa
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan (Y.-W.W.); (C.M.R.); (K.B.); (O.O.); (D.P.E.)
| | - Pawel L. Urban
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan (Y.-W.W.); (C.M.R.); (K.B.); (O.O.); (D.P.E.)
- Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan
| |
Collapse
|
4
|
Hsu CY, Prabhu GRD, Chang CH, Hsu PC, Buchowiecki K, Urban PL. Are Most Micrometer Droplets (>10 μm) Wasted in Electrospray Ionization? An Insight from Real-Time High-Speed Imaging. Anal Chem 2023; 95:14702-14709. [PMID: 37725015 DOI: 10.1021/acs.analchem.3c02799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
Electrospray ionization (ESI) is one of the main techniques used in mass spectrometry (MS) of nonvolatile compounds. ESI is a disordered process, in which a large number of polydisperse droplets are projected from a fluctuating Taylor cone and jet protruding ESI emitter. Here, we disclose a system for sectioning electrospray plumes to discrete packets with millisecond and submillisecond lifetime, which are introduced to the MS orifice, one at a time. A high-speed camera was triggered at 10,000 frames per second to capture consecutive images of the electrospray packets transmitted to the mass spectrometer. We further correlated the high-speed images of electrospray packets with MS signals of a test analyte (acetaminophen). Following computational treatment of the images, we determined the number of droplet observations (<300), average diameter of droplets (∼10-20 μm), and average volume of droplets (few tens of picoliters) in the individual electrospray packets. The result shows that most micrometer droplets (>10 μm) do not have any significant contribution to the MS signals. This finding is in agreement with the prior conjecture that most of the MS signals are mainly attributed to nanodroplets. Based on this finding, one can deduce that only a small number of the initial microdroplets effectively carry analyte molecules that undergo ionization. We discuss that, in future, one may propose a way to "recharge" the emitted initial micrometer droplets to increase the efficiency of conventional ESI setups.
Collapse
Affiliation(s)
- Chun-Yao Hsu
- Department of Chemistry, National Tsing Hua University 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan
| | - Gurpur Rakesh D Prabhu
- Department of Chemistry, National Tsing Hua University 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan
| | - Ching-Han Chang
- Department of Chemistry, National Tsing Hua University 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan
| | - Pin-Chieh Hsu
- Department of Chemistry, National Tsing Hua University 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan
| | - Krzysztof Buchowiecki
- Department of Chemistry, National Tsing Hua University 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan
| | - Pawel L Urban
- Department of Chemistry, National Tsing Hua University 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan
- Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan
| |
Collapse
|
5
|
Gadzuk-Shea MM, Hubbard EE, Gozzo TA, Bush MF. Sample pH Can Drift during Native Mass Spectrometry Experiments: Results from Ratiometric Fluorescence Imaging. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:1675-1684. [PMID: 37405934 PMCID: PMC10563179 DOI: 10.1021/jasms.3c00147] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/07/2023]
Abstract
The ability of nanoelectrospray ionization (nanoESI) to generate a continuous flow of charged droplets relies on the electrolytic nature of the process. This electrochemistry can lead to the accumulation of redox products in the sample solution. This consequence can have significant implications for native mass spectrometry (MS), which aims to probe the structures and interactions of biomolecules in solution. Here, ratiometric fluorescence imaging and a pH-sensitive, fluorescent probe are used to quantify changes in solution pH during nanoESI under conditions relevant to native MS. Results show that the extent and rate of change in sample pH depends on several experimental parameters. There is a strong correlation between the extent and rate of change in solution pH and the magnitude of both the nanoESI current and electrolyte concentration. Smaller changes in solution pH are observed during experiments when a negative potential is applied than for those when a positive potential is applied. Finally, we make specific recommendations for designing native MS experiments that control for these effects.
Collapse
Affiliation(s)
- Meagan M. Gadzuk-Shea
- University of Washington, Department of Chemistry, Box 351700, Seattle, WA 98195-1700
- Current Affiliation: Discovery Biology, Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Waltham, MA 02451
| | - Evan E. Hubbard
- University of Washington, Department of Chemistry, Box 351700, Seattle, WA 98195-1700
- Current Affiliation: Current Affiliation: Department of Chemistry, University of California, Riverside, California 92521
| | - Theresa A. Gozzo
- University of Washington, Department of Chemistry, Box 351700, Seattle, WA 98195-1700
| | - Matthew F Bush
- University of Washington, Department of Chemistry, Box 351700, Seattle, WA 98195-1700
| |
Collapse
|
6
|
Mostafa ME, Hayes MM, Grinias JP, Bythell BJ, Edwards JL. Supercritical Fluid Nanospray Mass Spectrometry: II. Effects on Ionization. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023. [PMID: 37097105 DOI: 10.1021/jasms.2c00372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Nanospraying supercritical fluids coupled to a mass spectrometer (nSF-MS) using a 90% supercritical fluid CO2 carrier (sCO2) has shown an enhanced desolvation compared to traditional liquid eluents. Capillaries of 25, 50, and 75 μm internal diameter (i.d.) with pulled emitter tips provided high MS detection sensitivity. Presented here is an evaluation of the effect of proton affinity, hydrophobicity, and nanoemitter tip size on the nSF-MS signal. This was done using a set of primary, secondary, tertiary, and quaternary amines with butyl, hexyl, octyl, and decyl chains as analytes. Each amine class was analyzed individually to evaluate hydrophobicity and proton affinity effects on signal intensity. The system has shown a mass sensitive detection on a linear dynamic range of 0.1-100 μM. Results indicate that hydrophobicity has a larger effect on the signal response than proton affinity. Nanospraying a mixture of all amine classes using the 75 μm emitter has shown a quaternary amine signal not suppressed by competing analytes. Competing ionization was observed for primary, secondary, and tertiary amines. The 75 and 50 μm emitters demonstrated increased signal with increasing hydrophobicity. Surprisingly, the 25 μm i.d. emitter yielded a signal decrease as the alkyl chain length increased, contrary to conventional understanding. Nanospraying the evaporative fluid in a sub-500 nm emitter likely resulted in differences in the ionization mechanism. Results suggest that 90% sCO2 with 9.99% methanol and 0.01% formic acid yielded fast desolvation, high ionization efficiency, and low matrix effect, which could benefit complex biological matrix analysis.
Collapse
Affiliation(s)
- Mahmoud Elhusseiny Mostafa
- Department of Chemistry and Biochemistry, Saint Louis University, 3501 Laclede Ave., St. Louis, Missouri 63103, United States
| | - Madisyn M Hayes
- Department of Chemistry and Biochemistry, Ohio University, 307 Chemistry Building, Athens, Ohio 45701, United States
| | - James P Grinias
- Department of Chemistry and Biochemistry, Rowan University, 201 Mullica Hill Rd., Glassboro, New Jersey 08028, United States
| | - Benjamin J Bythell
- Department of Chemistry and Biochemistry, Ohio University, 307 Chemistry Building, Athens, Ohio 45701, United States
| | - James L Edwards
- Department of Chemistry and Biochemistry, Saint Louis University, 3501 Laclede Ave., St. Louis, Missouri 63103, United States
| |
Collapse
|
7
|
Christofi E, Barran P. Ion Mobility Mass Spectrometry (IM-MS) for Structural Biology: Insights Gained by Measuring Mass, Charge, and Collision Cross Section. Chem Rev 2023; 123:2902-2949. [PMID: 36827511 PMCID: PMC10037255 DOI: 10.1021/acs.chemrev.2c00600] [Citation(s) in RCA: 43] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Indexed: 02/26/2023]
Abstract
The investigation of macromolecular biomolecules with ion mobility mass spectrometry (IM-MS) techniques has provided substantial insights into the field of structural biology over the past two decades. An IM-MS workflow applied to a given target analyte provides mass, charge, and conformation, and all three of these can be used to discern structural information. While mass and charge are determined in mass spectrometry (MS), it is the addition of ion mobility that enables the separation of isomeric and isobaric ions and the direct elucidation of conformation, which has reaped huge benefits for structural biology. In this review, where we focus on the analysis of proteins and their complexes, we outline the typical features of an IM-MS experiment from the preparation of samples, the creation of ions, and their separation in different mobility and mass spectrometers. We describe the interpretation of ion mobility data in terms of protein conformation and how the data can be compared with data from other sources with the use of computational tools. The benefit of coupling mobility analysis to activation via collisions with gas or surfaces or photons photoactivation is detailed with reference to recent examples. And finally, we focus on insights afforded by IM-MS experiments when applied to the study of conformationally dynamic and intrinsically disordered proteins.
Collapse
Affiliation(s)
- Emilia Christofi
- Michael Barber Centre for Collaborative
Mass Spectrometry, Manchester Institute of Biotechnology, University of Manchester, Princess Street, Manchester M1 7DN, United Kingdom
| | - Perdita Barran
- Michael Barber Centre for Collaborative
Mass Spectrometry, Manchester Institute of Biotechnology, University of Manchester, Princess Street, Manchester M1 7DN, United Kingdom
| |
Collapse
|
8
|
Yu W, Zhang G, Wu D, Guo L, Huang X, Ning F, Liu Y, Luo L. Identification of the botanical origins of honey based on nanoliter electrospray ionization mass spectrometry. Food Chem 2023; 418:135976. [PMID: 36963136 DOI: 10.1016/j.foodchem.2023.135976] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 02/21/2023] [Accepted: 03/15/2023] [Indexed: 03/26/2023]
Abstract
The botanical origins of honey are important for the quality control and commercialization of honey. In this research, we established a nanoliter electrospray ionization mass spectrometry (Nano-ESI-MS) method to identify Castanopsis honey (CH), Eurya honey (EH), Dendropanax dentiger honey (DH), and Triadica cochinchinensis honey (TH). In total, 38 compounds were identified based on the collision-induced dissociation experiments by Nano-ESI-MS with 16 differential compounds and 7 quantified as potential differential markers. These four types of honey were distinguished from each other by their mass spectrometry data combined with multivariate analysis with three out of the 7 differential markers, i.e., phenethylamine, tricoumaroyl spermidine, and (+/-)-abscisic acid, identified as potential markers for CH, EH, and DH, respectively. Both the qualitative and quantitative results derived from Nano-ESI-MS were further verified by UPLC-Q/TOF-MS. Our studies provided the significant potential of the Nano-ESI-MS method in the identification of the botanical origins of different kinds of honey.
Collapse
Affiliation(s)
- Wenjie Yu
- College of Food and Health, Beijing Technology and Business University (BTBU), Beijing 100048, China; School of Life Sciences, Nanchang University, Nanchang 330031, China
| | - Gaowei Zhang
- School of Life Sciences, Nanchang University, Nanchang 330031, China
| | - Dong Wu
- School of Life Sciences, Nanchang University, Nanchang 330031, China
| | - Limin Guo
- School of Life Sciences, Nanchang University, Nanchang 330031, China
| | - Xueyong Huang
- School of Life Sciences, Nanchang University, Nanchang 330031, China
| | - Fangjian Ning
- College of Food and Health, Beijing Technology and Business University (BTBU), Beijing 100048, China
| | - Yongquan Liu
- School of Life Sciences, Nanchang University, Nanchang 330031, China; College of Life Sciences, Gannan Normal University, Ganzhou 341000, China
| | - Liping Luo
- College of Food and Health, Beijing Technology and Business University (BTBU), Beijing 100048, China.
| |
Collapse
|
9
|
Wang YW, Prabhu GRD, Hsu CY, Urban PL. Tuning Electrospray Ionization with Low-Frequency Sound. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:1883-1890. [PMID: 36040001 DOI: 10.1021/jasms.2c00179] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Electrospray ionization (ESI) mass spectrometry (MS) is one of the key techniques used in biomolecular analysis nowadays. It relies on formation of polydisperse microdroplets, which undergo desolvation and liberate ions to the gas phase. Here we demonstrate low-frequency-sound-modulated ESI for analysis of biomolecules. By using a low-frequency (50-350 Hz) sound, it is possible to deflect electrospray microdroplets toward the mass spectrometer's orifice. Microdroplets of different sizes are deflected to a different extent leading to a partial size segregation. This effect leads to either an increase or decrease of MS signal intensity as well as signal-to-noise ratio. It also affects the selectivity of the ESI-MS analysis. The observations are rationalized by taking into account different pathways of ion formation and the likelihood of deflecting microdroplets of certain size. The online ESI-MS observations are supported with offline shadowgraphs obtained at varied sound frequencies, signal amplitudes, and phase shifts.
Collapse
Affiliation(s)
- Yi-Wun Wang
- Department of Chemistry, National Tsing Hua University 101, Section 2, Kuang-Fu Rd, Hsinchu 300044, Taiwan
| | - Gurpur Rakesh D Prabhu
- Department of Chemistry, National Tsing Hua University 101, Section 2, Kuang-Fu Rd, Hsinchu 300044, Taiwan
| | - Chun-Yao Hsu
- Department of Chemistry, National Tsing Hua University 101, Section 2, Kuang-Fu Rd, Hsinchu 300044, Taiwan
| | - Pawel L Urban
- Department of Chemistry, National Tsing Hua University 101, Section 2, Kuang-Fu Rd, Hsinchu 300044, Taiwan
- Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University 101, Section 2, Kuang-Fu Rd, Hsinchu 300044, Taiwan
| |
Collapse
|
10
|
Mostafa ME, Grinias JP, Edwards JL. Supercritical Fluid Nanospray Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:1825-1832. [PMID: 36049155 DOI: 10.1021/jasms.2c00134] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Supercritical fluids are typically electrosprayed using an organic solvent makeup flow to facilitate continuous electrical connection and enhancement of electrospray stability. This results in sample dilution, loss in sensitivity, and potential phase separation. Premixing the supercritical fluid with organic solvent has shown substantial benefits to electrospray efficiency and increased analyte charge state. Presented here is a nanospray mass spectrometry system for supercritical fluids (nSF-MS). This split flow system used small i.d. capillaries, heated interface, inline frit, and submicron emitter tips to electrospray quaternary alkyl amines solvated in supercritical CO2 with a 10% methanol modifier. Analyte signal response was evaluated as a function of total system flow rate (0.5-1.5 mL/min) that is split to nanospray a supercritical fluid with linear flow rates between 0.07 and 0.42 cm/sec and pressure ranges (15-25 MPa). The nSF system showed mass-sensitive detection based on increased signal intensity for increasing capillary i.d. and analyte injection volume. These effects indicate efficient solvent evaporation for the analysis of quaternary amines. Carrier additives generally decreased signal intensity. Comparison of the nSF-MS system to the conventional SF makeup flow ESI showed 10-fold signal intensity enhancement across all the capillary i.d.s. The nSF-MS system likely achieves rapid solvent evaporation of the SF at the emitter point. The developed system combined the benefits of the nanoemitters, sCO2, and the low modifier percentage which gave rise to enhancement in MS detection sensitivity.
Collapse
Affiliation(s)
- Mahmoud Elhusseiny Mostafa
- Department of Chemistry and Biochemistry, Saint Louis University, 3501 Laclede Avenue, St. Louis, Missouri 63103, United States
| | - James P Grinias
- Department of Chemistry and Biochemistry, Rowan University, 201 Mullica Hill Road, Glassboro, New Jersey 08028, United States
| | - James L Edwards
- Department of Chemistry and Biochemistry, Saint Louis University, 3501 Laclede Avenue, St. Louis, Missouri 63103, United States
| |
Collapse
|
11
|
Zhang Y, Li K, Zhao Y, Shi W, Iyer H, Kim S, Brenden C, Sweedler JV, Vlasov Y. Attomole-Level Multiplexed Detection of Neurochemicals in Picoliter Droplets by On-Chip Nanoelectrospray Ionization Coupled to Mass Spectrometry. Anal Chem 2022; 94:13804-13809. [PMID: 36166829 PMCID: PMC9558086 DOI: 10.1021/acs.analchem.2c02323] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
While droplet microfluidics is becoming an effective
tool for biomedical research,
sensitive detection of droplet content is still challenging, especially
for multiplexed analytes compartmentalized within ultrasmall droplets
down to picoliter volumes. To enable such measurements, we demonstrate
a silicon-based integrated microfluidic platform for multiplexed analysis
of neurochemicals in picoliter droplets via nanoelectrospray ionization
(nESI)-mass spectrometry (MS). An integrated silicon microfluidic
chip comprising downscaled 7 μm-radius channels, a compact T-junction
for droplet generation, and an integrated nESI emitter tip is used
for segmentation of analytes into picoliter compartments and their
efficient delivery for subsequent MS detection. The developed system
demonstrates effective detection of multiple neurochemicals encapsulated
within oil-isolated plugs down to low picoliter volumes. Quantitative
measurements for each neurochemical demonstrate limits of detection
at the attomole level. Such results are promising for applications
involving label-free and small-volume detection for monitoring a range
of brain chemicals.
Collapse
Affiliation(s)
- Yan Zhang
- Department of Electrical and Computer Engineering, University of Illinois Urbana Champaign, Urbana, Illinois 61801, United States
| | - Keyin Li
- Department of Chemistry and the Beckman Institute, University of Illinois Urbana Champaign, Urbana, Illinois 61801, United States
| | - Yaoyao Zhao
- Department of Chemistry and the Beckman Institute, University of Illinois Urbana Champaign, Urbana, Illinois 61801, United States
| | - Weihua Shi
- Department of Electrical and Computer Engineering, University of Illinois Urbana Champaign, Urbana, Illinois 61801, United States
| | - Hrishikesh Iyer
- Department of Electrical and Computer Engineering, University of Illinois Urbana Champaign, Urbana, Illinois 61801, United States
| | - Sungho Kim
- Department of Electrical and Computer Engineering, University of Illinois Urbana Champaign, Urbana, Illinois 61801, United States
| | - Christopher Brenden
- Department of Bioengineering, University of Illinois Urbana Champaign, Urbana, Illinois 61801, United States
| | - Jonathan V Sweedler
- Department of Chemistry and the Beckman Institute, University of Illinois Urbana Champaign, Urbana, Illinois 61801, United States
| | - Yurii Vlasov
- Department of Electrical and Computer Engineering, University of Illinois Urbana Champaign, Urbana, Illinois 61801, United States.,Department of Bioengineering, University of Illinois Urbana Champaign, Urbana, Illinois 61801, United States
| |
Collapse
|
12
|
Covey T. Where have all the ions gone, long time passing? Tandem quadrupole mass spectrometers with atmospheric pressure ionization sensitivity gains since the mid-1970s. A perspective. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2022:e9354. [PMID: 35830299 DOI: 10.1002/rcm.9354] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/09/2022] [Accepted: 07/07/2022] [Indexed: 06/15/2023]
Abstract
The gains in sensitivity since 1975 for quadrupole mass spectrometers equipped with atmospheric pressure ionization (API), and in particular triple quadrupole mass spectrometers (QqQs) since 1981, have been driven by the needs of the environmental, biomedical, agricultural, and other scientific research, industrial, regulatory, legal, and sporting communities to continually achieve lower limits of quantitation and identification. QqQs have realized a one-million-fold improvement in sensitivity attempting to address these needs over the past two score years. It is the purpose of this article to describe how that came about, not through an exhaustive review of the literature, but rather by describing what general approaches were used across the industry to improve sensitivity and provide some examples to illustrate its evolution. The majority of the gains came from the ion source and its interface to the vacuum system. "Sampling efficiency" is a measurement of the losses in this area so will be a focus of this review. The discovery of the phenomenon of collisional focusing was key to improving sampling efficiency because it enabled designs that increased the ion-containing gas loads from the ion source, using staged differential pumping backed by increasingly larger pumps, and prevented the scattering losses of ions in the resulting gas expansion inside vacuum. Likewise, systems with smaller pumps and lower ion-containing gas loads could be designed with size and cost reduction in mind while maintaining reasonable sampling efficiencies. As a consequence, advancements in the designs of both larger and smaller turbomolecular vacuum pumps were accelerated by pump manufacturers to accommodate the explosive growth in the use of API-QqQ and API-ion trap mass spectrometers that occurred in the 1990s and continued into the new millennium. Sampling efficiency was further improved by increasing the ion yield from electrospray by increasing the rate of droplet desolvation. An estimate of the practical limit to further sensitivity improvements beyond what has been achieved to date is provided to shed light on what to expect in the future. Lastly, the implications and unforeseen consequences of the sensitivity gains are considered with a particular focus on how they have enabled a dramatic increase in daily sample throughput on triple quadrupole and other types of mass spectrometers.
Collapse
|
13
|
Liu R, Xia S, Li H. Native top-down mass spectrometry for higher-order structural characterization of proteins and complexes. MASS SPECTROMETRY REVIEWS 2022:e21793. [PMID: 35757976 DOI: 10.1002/mas.21793] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 05/23/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
Progress in structural biology research has led to a high demand for powerful and yet complementary analytical tools for structural characterization of proteins and protein complexes. This demand has significantly increased interest in native mass spectrometry (nMS), particularly native top-down mass spectrometry (nTDMS) in the past decade. This review highlights recent advances in nTDMS for structural research of biological assemblies, with a particular focus on the extra multi-layers of information enabled by TDMS. We include a short introduction of sample preparation and ionization to nMS, tandem fragmentation techniques as well as mass analyzers and software/analysis pipelines used for nTDMS. We highlight unique structural information offered by nTDMS and examples of its broad range of applications in proteins, protein-ligand interactions (metal, cofactor/drug, DNA/RNA, and protein), therapeutic antibodies and antigen-antibody complexes, membrane proteins, macromolecular machineries (ribosome, nucleosome, proteosome, and viruses), to endogenous protein complexes. The challenges, potential, along with perspectives of nTDMS methods for the analysis of proteins and protein assemblies in recombinant and biological samples are discussed.
Collapse
Affiliation(s)
- Ruijie Liu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Shujun Xia
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Huilin Li
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
- Guangdong Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| |
Collapse
|
14
|
Walz A, Stoiber K, Huettig A, Schlichting H, Barth JV. Navigate Flying Molecular Elephants Safely to the Ground: Mass-Selective Soft Landing up to the Mega-Dalton Range by Electrospray Controlled Ion-Beam Deposition. Anal Chem 2022; 94:7767-7778. [PMID: 35609119 PMCID: PMC9178560 DOI: 10.1021/acs.analchem.1c04495] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The prototype of a highly versatile and efficient preparative mass spectrometry system used for the deposition of molecules in ultrahigh vacuum (UHV) is presented, along with encouraging performance data obtained using four model species that are thermolabile or not sublimable. The test panel comprises two small organic compounds, a small and very large protein, and a large DNA species covering a 4-log mass range up to 1.7 MDa as part of a broad spectrum of analyte species evaluated to date. Three designs of innovative ion guides, a novel digital mass-selective quadrupole (dQMF), and a standard electrospray ionization (ESI) source are combined to an integrated device, abbreviated electrospray controlled ion-beam deposition (ES-CIBD). Full control is achieved by (i) the square-wave-driven radiofrequency (RF) ion guides with steadily tunable frequencies, including a dQMF allowing for investigation, purification, and deposition of a virtually unlimited m/z range, (ii) the adjustable landing energy of ions down to ∼2 eV/z enabling integrity-preserving soft landing, (iii) the deposition in UHV with high ion beam intensity (up to 3 nA) limiting contaminations and deposition time, and (iv) direct coverage control via the deposited charge. The maximum resolution of R = 650 and overall efficiency up to Ttotal = 4.4% calculated from the solution to UHV deposition are advantageous, whereby the latter can be further enhanced by optimizing ionization performance. In the setup presented, a scanning tunneling microscope (STM) is attached for in situ UHV investigations of deposited species, demonstrating a selective, structure-preserving process and atomically clean layers.
Collapse
Affiliation(s)
- Andreas Walz
- Physics Department E20, Technical University of Munich, 85748 Garching, Germany
| | - Karolina Stoiber
- Physics Department E20, Technical University of Munich, 85748 Garching, Germany
| | - Annette Huettig
- Physics Department E20, Technical University of Munich, 85748 Garching, Germany
| | - Hartmut Schlichting
- Physics Department E20, Technical University of Munich, 85748 Garching, Germany
| | - Johannes V Barth
- Physics Department E20, Technical University of Munich, 85748 Garching, Germany
| |
Collapse
|
15
|
Li W, Chaihu L, Jiang J, Wu B, Zheng X, Dai R, Tian Y, Huang Y, Wang G, Men Y. Microfluidic Platform for Time-Resolved Characterization of Protein Higher-Order Structures and Dynamics Using Top-Down Mass Spectrometry. Anal Chem 2022; 94:7520-7527. [PMID: 35584038 DOI: 10.1021/acs.analchem.2c00077] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Characterization of protein higher-order structures and dynamics is essential for understanding the biological functions of proteins and revealing the underlying mechanisms. Top-down mass spectrometry (MS) accesses structural information at both the intact protein level and the peptide fragment level. Native top-down MS allows analysis of a protein complex's architecture and subunits' identity and modifications. Top-down hydrogen/deuterium exchange (HDX) MS offers high spatial resolution for conformational or binding interface analysis and enables conformer-specific characterization. A microfluidic chip can provide superior performance for front-end reactions useful for these MS workflows, such as flexibility in manipulating multiple reactant flows, integrating various functional modules, and automation. However, most microchip-MS devices are designed for bottom-up approaches or top-down proteomics. Here, we demonstrate a strategy for designing a microchip for top-down MS analysis of protein higher-order structures and dynamics. It is suitable for time-resolved native MS and HDX MS, with designs aiming for efficient ionization of intact protein complexes, flexible manipulation of multiple reactant flows, and precise control of reaction times over a broad range of flow rates on the submicroliter per minute scale. The performance of the prototype device is demonstrated by measurements of systems including monoclonal antibodies, antibody-antigen complexes, and coexisting protein conformers. This strategy may benefit elaborate structural analysis of biomacromolecules and inspire method development using the microchip-MS approach.
Collapse
Affiliation(s)
- Wen Li
- Research Center for Biomedical Optics and Molecular Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Lingxiao Chaihu
- School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China.,Institute of Cell Analysis, Shenzhen Bay Laboratory, Shenzhen 518132, China
| | - Jialu Jiang
- School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Bizhu Wu
- Research Center for Biomedical Optics and Molecular Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Xuan Zheng
- Research Center for Biomedical Optics and Molecular Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Rongrong Dai
- School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China
| | - Ye Tian
- Institute of Cell Analysis, Shenzhen Bay Laboratory, Shenzhen 518132, China
| | - Yanyi Huang
- Institute of Cell Analysis, Shenzhen Bay Laboratory, Shenzhen 518132, China.,Biomedical Pioneering Innovation Centre, Peking University, Beijing 100871, China
| | - Guanbo Wang
- Institute of Cell Analysis, Shenzhen Bay Laboratory, Shenzhen 518132, China.,Biomedical Pioneering Innovation Centre, Peking University, Beijing 100871, China
| | - Yongfan Men
- Research Center for Biomedical Optics and Molecular Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| |
Collapse
|
16
|
Lipidomics in Understanding Pathophysiology and Pharmacologic Effects in Inflammatory Diseases: Considerations for Drug Development. Metabolites 2022; 12:metabo12040333. [PMID: 35448520 PMCID: PMC9030008 DOI: 10.3390/metabo12040333] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 03/29/2022] [Accepted: 04/04/2022] [Indexed: 01/26/2023] Open
Abstract
The lipidome has a broad range of biological and signaling functions, including serving as a structural scaffold for membranes and initiating and resolving inflammation. To investigate the biological activity of phospholipids and their bioactive metabolites, precise analytical techniques are necessary to identify specific lipids and quantify their levels. Simultaneous quantification of a set of lipids can be achieved using high sensitivity mass spectrometry (MS) techniques, whose technological advancements have significantly improved over the last decade. This has unlocked the power of metabolomics/lipidomics allowing the dynamic characterization of metabolic systems. Lipidomics is a subset of metabolomics for multianalyte identification and quantification of endogenous lipids and their metabolites. Lipidomics-based technology has the potential to drive novel biomarker discovery and therapeutic development programs; however, appropriate standards have not been established for the field. Standardization would improve lipidomic analyses and accelerate the development of innovative therapies. This review aims to summarize considerations for lipidomic study designs including instrumentation, sample stabilization, data validation, and data analysis. In addition, this review highlights how lipidomics can be applied to biomarker discovery and drug mechanism dissection in various inflammatory diseases including cardiovascular disease, neurodegeneration, lung disease, and autoimmune disease.
Collapse
|
17
|
Shan L, Jones B. Nano liquid chromatography, an updated review. Biomed Chromatogr 2022; 36:e5317. [PMID: 34981550 DOI: 10.1002/bmc.5317] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 12/04/2021] [Accepted: 12/09/2021] [Indexed: 11/11/2022]
Abstract
Low flow chromatography has a rich history of innovation but has yet to reach widespread implementation in bioanalytical applications. Improvements in pump technology, microfluidic connections, and nano-electrospray sources for mass spectrometry have laid the groundwork for broader application, and innovation in this space has accelerated in recent years. This article reviews the instrumentation used for nano-flow liquid chromatography , the types of columns employed, and strategies for multi-dimensionality of separations, which is key to the future state of the technique to the high-throughput needs of modern bioanalysis. An update of the current applications where nano-LC is widely used, such as proteomics and metabolomics, is discussed. But the trend towards biopharmaceutical development of increasingly complex, targeted, and potent therapeutics for the safe treatment of disease drives the need for ultimate selectivity and sensitivity of our analytical platforms for targeted quantitation in a regulated space. The selectivity needs are best addressed by mass spectrometric detection, especially at high resolutions, and exquisite sensitivity is provided by nano-electrospray ionization as the technology continues to evolve into an accessible, robust, and easy to use platform.
Collapse
|
18
|
Fedorenko D, Bartkevics V. Recent Applications of Nano-Liquid Chromatography in Food Safety and Environmental Monitoring: A Review. Crit Rev Anal Chem 2021; 53:98-122. [PMID: 34392753 DOI: 10.1080/10408347.2021.1938968] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
In recent years, a trend toward instrument miniaturization has led to the development of new and sophisticated analytical systems, such as nano-liquid chromatography (nano-LC), which has enabled improvements of sensitivity, as well as chromatographic resolution. The growing interest in nano-LC methodology has resulted in a variety of innovative and promising applications. In this article, we review the applications of nano-LC separation methods coupled with mass spectrometry in the analysis of food and environmental samples. An assessment of sample preparation methods and analytical performance are provided, along with comparison to other, more established analytical techniques. Three main groups of compounds that are crucial for food safety assessment are considered in this review: pharmaceuticals (including antibiotics), pesticides, and mycotoxins. Recent practical applications of the nano-LC method in the determination of these compounds are discussed. Furthermore, we also focus on methods for the determination of various environmental contaminants using nano-LC methods. Future perspectives for the development of nano-LC methods are discussed.
Collapse
Affiliation(s)
- Deniss Fedorenko
- Institute of Food Safety, Animal Health and Environment "BIOR", Riga, Latvia.,University of Latvia, Faculty of Chemistry, Riga, Latvia
| | - Vadims Bartkevics
- Institute of Food Safety, Animal Health and Environment "BIOR", Riga, Latvia.,University of Latvia, Faculty of Chemistry, Riga, Latvia
| |
Collapse
|
19
|
Bahureksa W, Tfaily MM, Boiteau RM, Young RB, Logan MN, McKenna AM, Borch T. Soil Organic Matter Characterization by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FTICR MS): A Critical Review of Sample Preparation, Analysis, and Data Interpretation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:9637-9656. [PMID: 34232025 DOI: 10.1021/acs.est.1c01135] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The biogeochemical cycling of soil organic matter (SOM) plays a central role in regulating soil health, water quality, carbon storage, and greenhouse gas emissions. Thus, many studies have been conducted to reveal how anthropogenic and climate variables affect carbon sequestration and nutrient cycling. Among the analytical techniques used to better understand the speciation and transformation of SOM, Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) is the only technique that has sufficient mass resolving power to separate and accurately assign elemental compositions to individual SOM molecules. The global increase in the application of FTICR MS to address SOM complexity has highlighted the many challenges and opportunities associated with SOM sample preparation, FTICR MS analysis, and mass spectral interpretation. Here, we provide a critical review of recent strategies for SOM characterization by FTICR MS with emphasis on SOM sample collection, preparation, analysis, and data interpretation. Data processing and visualization methods are presented with suggested workflows that detail the considerations needed for the application of molecular information derived from FTICR MS. Finally, we highlight current research gaps, biases, and future directions needed to improve our understanding of organic matter chemistry and cycling within terrestrial ecosystems.
Collapse
Affiliation(s)
- William Bahureksa
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Malak M Tfaily
- Department of Environmental Science, University of Arizona, Tucson, Arizona 85721, United States
| | - Rene M Boiteau
- College of Earth, Ocean, Atmospheric Sciences, Oregon State University, Corvallis, Oregon 97331, United States
| | - Robert B Young
- Department of Soil and Crop Sciences, Colorado State University, Fort Collins, Colorado 80523-1170, United States
| | - Merritt N Logan
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Amy M McKenna
- National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Dr., Tallahassee, Florida 32310-4005, United States
| | - Thomas Borch
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
- Department of Soil and Crop Sciences, Colorado State University, Fort Collins, Colorado 80523-1170, United States
| |
Collapse
|
20
|
Raab SA, El-Baba TJ, Laganowsky A, Russell DH, Valentine SJ, Clemmer DE. Protons Are Fast and Smart; Proteins Are Slow and Dumb: On the Relationship of Electrospray Ionization Charge States and Conformations. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:1553-1561. [PMID: 34151568 PMCID: PMC9003666 DOI: 10.1021/jasms.1c00100] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We present simple considerations of how differences in time scales of motions of protons, the lightest and fastest chemical moiety, and the much longer time scales associated with the dynamics of proteins, among the heaviest and slowest analytes, may allow many protein conformations from solution to be kinetically trapped during the process of electrospraying protein solutions into the gas phase. In solution, the quantum nature of protons leads them to change locations by tunneling, an instantaneous process; moreover, the Grotthuss mechanism suggests that these small particles can respond nearly instantaneously to the dynamic motions of proteins that occur on much longer time scales. A conformational change is accompanied by favorable or unfavorable variations in the free energy of the system, providing the impetus for solvent ↔ protein proton exchange. Thus, as thermal distributions of protein conformations interconvert, protonation states rapidly respond, as specific acidic and basic sites are exposed or protected. In the vacuum of the mass spectrometer, protons become immobilized in locations that are specific to the protein conformations from which they were incorporated. In this way, conformational states from solution are preserved upon electrospraying them into the gas phase. These ideas are consistent with the exquisite sensitivity of electrospray mass spectra to small changes of the local environment that alter protein structure in solution. We might remember this approximation for the protonation of proteins in solution with the colloquial expression-protons are fast and smart; proteins are slow and dumb.
Collapse
Affiliation(s)
- Shannon A Raab
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Tarick J El-Baba
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Arthur Laganowsky
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - David H Russell
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Stephen J Valentine
- Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - David E Clemmer
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| |
Collapse
|
21
|
Alfaro JA, Bohländer P, Dai M, Filius M, Howard CJ, van Kooten XF, Ohayon S, Pomorski A, Schmid S, Aksimentiev A, Anslyn EV, Bedran G, Cao C, Chinappi M, Coyaud E, Dekker C, Dittmar G, Drachman N, Eelkema R, Goodlett D, Hentz S, Kalathiya U, Kelleher NL, Kelly RT, Kelman Z, Kim SH, Kuster B, Rodriguez-Larrea D, Lindsay S, Maglia G, Marcotte EM, Marino JP, Masselon C, Mayer M, Samaras P, Sarthak K, Sepiashvili L, Stein D, Wanunu M, Wilhelm M, Yin P, Meller A, Joo C. The emerging landscape of single-molecule protein sequencing technologies. Nat Methods 2021; 18:604-617. [PMID: 34099939 PMCID: PMC8223677 DOI: 10.1038/s41592-021-01143-1] [Citation(s) in RCA: 172] [Impact Index Per Article: 57.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 04/02/2021] [Indexed: 02/04/2023]
Abstract
Single-cell profiling methods have had a profound impact on the understanding of cellular heterogeneity. While genomes and transcriptomes can be explored at the single-cell level, single-cell profiling of proteomes is not yet established. Here we describe new single-molecule protein sequencing and identification technologies alongside innovations in mass spectrometry that will eventually enable broad sequence coverage in single-cell profiling. These technologies will in turn facilitate biological discovery and open new avenues for ultrasensitive disease diagnostics.
Collapse
Affiliation(s)
- Javier Antonio Alfaro
- International Centre for Cancer Vaccine Science, University of Gdańsk, Gdańsk, Poland.
| | - Peggy Bohländer
- Faculty of Applied Sciences, Delft University of Technology, Delft, the Netherlands
| | - Mingjie Dai
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- Department of Systems Biology, Harvard Medical School, Boston, MA, USA
| | - Mike Filius
- Department of BioNanoScience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands
| | - Cecil J Howard
- Department of Chemistry, University of Texas at Austin, Austin, TX, USA
| | - Xander F van Kooten
- Department of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Shilo Ohayon
- Department of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Adam Pomorski
- Department of BioNanoScience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands
| | - Sonja Schmid
- NanoDynamicsLab, Laboratory of Biophysics, Wageningen University, Wageningen, the Netherlands
| | - Aleksei Aksimentiev
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Eric V Anslyn
- Department of Chemistry, University of Texas at Austin, Austin, TX, USA
| | - Georges Bedran
- International Centre for Cancer Vaccine Science, University of Gdańsk, Gdańsk, Poland
| | - Chan Cao
- Institute of Bioengineering, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Mauro Chinappi
- Dipartimento di Ingegneria Industriale, Università di Roma Tor Vergata, Rome, Italy
| | - Etienne Coyaud
- Univ. Lille, Inserm, CHU Lille, U1192-Protéomique Réponse Inflammatoire Spectrométrie de Masse-PRISM, Lille, France
| | - Cees Dekker
- Department of BioNanoScience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands
| | - Gunnar Dittmar
- Department of Infection and Immunity, Luxembourg Institute of Health, Strassen, Luxembourg
- Department of Life Sciences and Medicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | | | - Rienk Eelkema
- Faculty of Applied Sciences, Delft University of Technology, Delft, the Netherlands
| | - David Goodlett
- International Centre for Cancer Vaccine Science, University of Gdańsk, Gdańsk, Poland
- Genome BC Proteomics Centre, University of Victoria, Victoria, British Columbia, Canada
| | | | - Umesh Kalathiya
- International Centre for Cancer Vaccine Science, University of Gdańsk, Gdańsk, Poland
| | - Neil L Kelleher
- Departments of Chemistry and Molecular Biosciences, and the Feinberg School of Medicine, Northwestern University, Evanston, IL, USA
| | - Ryan T Kelly
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USA
| | - Zvi Kelman
- Institute for Bioscience and Biotechnology Research, National Institute of Standards and Technology, University of Maryland, Rockville, MD, USA
- Biomolecular Labeling Laboratory, Institute for Bioscience and Biotechnology Research, Rockville, MD, USA
| | - Sung Hyun Kim
- Department of BioNanoScience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands
| | - Bernhard Kuster
- Chair of Proteomics and Bioanalytics, Technische Universität München, Freising, Germany
- Bavarian Center for Biomolecular Mass Spectrometry, Freising, Germany
| | - David Rodriguez-Larrea
- Department of Biochemistry and Molecular Biology, Biofisika Institute (CSIC, UPV/EHU), Leioa, Spain
| | - Stuart Lindsay
- Biodesign Institute, School of Molecular Sciences, Department of Physics, Arizona State University, Tempe, AZ, USA
| | - Giovanni Maglia
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, the Netherlands
| | - Edward M Marcotte
- Department of Molecular Biosciences, Center for Systems and Synthetic Biology, University of Texas at Austin, Austin, TX, USA
| | - John P Marino
- Institute for Bioscience and Biotechnology Research, National Institute of Standards and Technology, University of Maryland, Rockville, MD, USA
| | | | - Michael Mayer
- Adolphe Merkle Institute, University of Fribourg, Fribourg, Switzerland
| | - Patroklos Samaras
- Chair of Proteomics and Bioanalytics, Technische Universität München, Freising, Germany
| | - Kumar Sarthak
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Lusia Sepiashvili
- University of Toronto, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Derek Stein
- Department of Physics, Brown University, Providence, RI, USA
| | - Meni Wanunu
- Department of Physics, Northeastern University, Boston, MA, USA
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, USA
| | - Mathias Wilhelm
- Chair of Proteomics and Bioanalytics, Technische Universität München, Freising, Germany
| | - Peng Yin
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
- Department of Systems Biology, Harvard Medical School, Boston, MA, USA
| | - Amit Meller
- Department of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa, Israel.
- Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa, Israel.
| | - Chirlmin Joo
- Department of BioNanoScience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, the Netherlands.
| |
Collapse
|
22
|
Development of a chromatography-free method for high-throughput MS-based bioanalysis of therapeutic monoclonal antibodies. Bioanalysis 2021; 13:725-735. [PMID: 33856232 DOI: 10.4155/bio-2021-0021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Aim: Our objective was to test the feasibility of developing an LC-free, MS-based approach for high-throughput bioanalysis of humanized therapeutic monoclonal antibodies. Methodology: A universal tryptic peptide from human IgG1, IgG3 and IgG4 was selected as the surrogate peptide for quantitation. After tryptic digestion, the surrogate peptide was fractionated via solid-phase extraction before being subjected to direct infusion-based MS/MS analysis. A high-resolution, multiplexed (MSX = 2) parallel reaction monitoring method was developed for data acquisition. Results & conclusion: This proof-of-concept study demonstrated the feasibility of achieving high-throughput MS-based bioanalysis of monoclonal antibodies using an LC-free workflow with sensitivity comparable to conventional LC-MS/MS-based methods.
Collapse
|
23
|
Kawai T. Recent Advances in Trace Bioanalysis by Capillary Electrophoresis. ANAL SCI 2021; 37:27-36. [PMID: 33041311 DOI: 10.2116/analsci.20sar12] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 09/29/2020] [Indexed: 07/25/2024]
Abstract
Recently, single cell analysis is becoming more and more important to elucidate cellular heterogeneity. Except for nucleic acid that can be amplified by PCR, the required technical level for single cell analysis is extremely high and the appropriate design of sample preparation and a sensitive analytical system is necessary. Capillary/microchip electrophoresis (CE/MCE) can separate biomolecules in nL-scale solution with high resolution, and it is highly compatible with trace samples like a single cell. Coupled with highly sensitive detectors such as laser-induced fluorescence and nano-electrospray ionization-mass spectrometry, zmol level analytes can be detected. For further enhancing sensitivity, online sample preconcentration techniques can be employed. By integrating these high-sensitive techniques, single cell analysis of metabolites, proteins, and lipids have been achieved. This review paper highlights successful research on CE/MCE-based trace bioanalysis in recent 10 years. Firstly, an overview of basic knowledge on CE/MCE including sensitivity enhancement techniques is provided. Applications to trace bioanalysis are then introduced with discussion on current issues and future prospects.
Collapse
Affiliation(s)
- Takayuki Kawai
- RIKEN Center for Biosystems Dynamics Research
- Graduate School of Frontier Biosciences, Osaka University
| |
Collapse
|
24
|
Ahmed E, Xiao D, Kabir KMM, Fletcher J, Donald WA. Ambient Pressure Ion Funnel: Concepts, Simulations, and Analytical Performance. Anal Chem 2020; 92:15811-15817. [DOI: 10.1021/acs.analchem.0c02938] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ezaz Ahmed
- School of Chemistry, University of New South Wales, Sydney, NSW 2052 Australia
| | - Dan Xiao
- School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW 2052 Australia
| | - K. M. Mohibul Kabir
- School of Chemistry, University of New South Wales, Sydney, NSW 2052 Australia
| | - John Fletcher
- School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, NSW 2052 Australia
| | - William A. Donald
- School of Chemistry, University of New South Wales, Sydney, NSW 2052 Australia
| |
Collapse
|
25
|
Sorensen MJ, Kennedy RT. Capillary ultrahigh-pressure liquid chromatography-mass spectrometry for fast and high resolution metabolomics separations. J Chromatogr A 2020; 1635:461706. [PMID: 33229007 DOI: 10.1016/j.chroma.2020.461706] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 11/04/2020] [Accepted: 11/09/2020] [Indexed: 12/15/2022]
Abstract
LC-MS is an important tool for metabolomics due its high sensitivity and broad metabolite coverage. The goal of improving resolution and decreasing analysis time in HPLC has led to the use of 5 - 15 cm long columns packed with 1.7 - 1.9 µm particles requiring pressures of 8 - 12 kpsi. We report on the potential for capillary LC-MS based metabolomics utilizing porous C18 particles down to 1.1 µm diameter and columns up to 50 cm long with an operating pressure of 35 kpsi. Our experiments show that it is possible to pack columns with 1.1 µm porous particles to provide predicted improvements in separation time and efficiency. Using kinetic plots to guide the choice of column length and particle size, we packed 50 cm long columns with 1.7 µm particles and 20 cm long columns with 1.1 µm particles, which should produce equivalent performance in shorter times. Columns were tested by performing isocratic and gradient LC-MS analyses of small molecule metabolites and extracts from plasma. These columns provided approximately 100,000 theoretical plates for metabolite standards and peak capacities over 500 in 100 min for a complex plasma extract with robust interfacing to MS. To generate a given peak capacity, the 1.1 µm particles in 20 cm columns required roughly 75% of the time as 1.7 µm particles in 50 cm columns with both operated at 35 kpsi. The 1.1 µm particle packed columns generated a given peak capacity nearly 3 times faster than 1.7 µm particles in 15 cm columns operated at ~10 kpsi. This latter condition represents commercial state of the art for capillary LC. To consider practical benefits for metabolomics, the effect of different LC-MS variables on mass spectral feature detection was evaluated. Lower flow rates (down to 700 nL/min) and larger injection volumes (up to 1 µL) increased the features detected with modest loss in separation performance. The results demonstrate the potential for fast and high resolution separations for metabolomics using 1.1 µm particles operated at 35 kpsi for capillary LC-MS.
Collapse
Affiliation(s)
- Matthew J Sorensen
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Robert T Kennedy
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA; Department of Pharmacology, University of Michigan, Ann Arbor, MI 48109, USA.
| |
Collapse
|
26
|
Prabhu GRD, Ponnusamy VK, Witek HA, Urban PL. Sample Flow Rate Scan in Electrospray Ionization Mass Spectrometry Reveals Alterations in Protein Charge State Distribution. Anal Chem 2020; 92:13042-13049. [PMID: 32893617 DOI: 10.1021/acs.analchem.0c01945] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sample flow rate is one of the parameters that influence the sensitivity of electrospray ionization (ESI) mass spectrometry. By varying the sample flow rate, initial droplets of different sizes can be generated. Protein molecules in small droplets may form gas-phase ions earlier than the ones in large droplets. Here, we have systematically studied the influence of sample flow rate on the ESI charge state distributions (CSDs) of model proteins. A dedicated programmable sample flow rate scanner was used to infuse protein samples at different flow rates into a mass spectrometer. The synergistic influence of sample flow rate and various electrolytes (ammonium acetate, ammonium bicarbonate, ammonium formate, and piperidine) was studied. Significant alterations to the CSDs with increasing flow rate were observed. For example, in the presence of ammonium acetate, at low flow rates, lower charge states of proteins showed high intensities, while at high flow rates, ions related to higher charge states of proteins dominated the spectra. On the other hand, in the presence of piperidine, a significant reduction in the ion currents of all charge states was observed during the flow rate scan. Our observations suggest that at low flow rates the protein molecules follow a charged residue model of ionization mechanism, and at high flow rates-due to structural changes in protein molecules in large ESI droplets-the charged residue and chain ejection models can possibly coexist. We propose the use of sample flow rate scan as a way to reveal the influence of flow rate on the CSDs of the studied proteins.
Collapse
Affiliation(s)
- Gurpur Rakesh D Prabhu
- Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan.,Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan
| | - Vinoth Kumar Ponnusamy
- Department of Medicinal and Applied Chemistry & Research Center for Environmental Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 807, Taiwan.,Department of Medical Research, Kaohsiung Medical University Hospital, 100 Shih-Chuan 1st Road, Kaohsiung 807, Taiwan
| | - Henryk A Witek
- Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan.,Center for Emergent Functional Matter Science, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan
| | - Pawel L Urban
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan.,Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan
| |
Collapse
|
27
|
Rivera-Albarran ME, Ray SJ. A Novel Combined Microstrip Resonator/Nanospray Ionization Source for Microwave-Assisted Trypsin Digestion of Proteins. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:1684-1696. [PMID: 32573245 DOI: 10.1021/jasms.0c00115] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Enzymatic digestion of proteins is a critical step in bottom-up and middle-down proteomics. Here, we demonstrate a method for decreasing the time required for proteolytic digestion of proteins from multiple hours to minutes by using an in-line microstrip cavity for programmed microwave heating. When a nanospray emitter tip, containing a digestion sample, is exposed to a region of highly focused microwave field, the rate of proteolytic digestion is enhanced and the time required for digestion greatly decreased. The design is advantageous for mass spectrometry because the solution-based digestion can then be directly sprayed from a nanoelectrospray tip emitter, decreasing sample transfer loss and allowing the system to be used in a flow-through proteolytic workflow. Microwave-assisted digestion using this method is evaluated against standard overnight digestion protocols using a variety of proteins, evaluating sequence coverage and observed peptide location, digestion rate, and overall efficacy. The influence of applied microwave power is investigated, and enzymatic kinetic parameters are evaluated to estimate temperature within the microreactor. Finally, the modulation of the proteolytic digestion of proteins based upon the modulation of applied microwave power is demonstrated on a time scale of seconds in a flow-through system.
Collapse
Affiliation(s)
- Maria E Rivera-Albarran
- Department of Chemistry, The State University of New York at Buffalo, Buffalo, New York 14260, United States
| | - Steven J Ray
- Department of Chemistry, The State University of New York at Buffalo, Buffalo, New York 14260, United States
| |
Collapse
|
28
|
Kourtchev I, Szeto P, O'Connor I, Popoola OAM, Maenhaut W, Wenger J, Kalberer M. Comparison of Heated Electrospray Ionization and Nanoelectrospray Ionization Sources Coupled to Ultra-High-Resolution Mass Spectrometry for Analysis of Highly Complex Atmospheric Aerosol Samples. Anal Chem 2020; 92:8396-8403. [PMID: 32394709 DOI: 10.1021/acs.analchem.0c00971] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Direct infusion analysis using soft ionization techniques coupled to ultra-high-resolution mass spectrometers (UHRMS) allows screening of thousands of organic species in complex samples. Despite the high analytical throughput of direct infusion, this technique is known to be prone to matrix effects caused by changes in the ionization efficiency of an analyte, ion suppression, or enhancement due to the presence of certain compounds and inorganic salts in the sample. In this study we compared two soft ionization sources, that is, heated electrospray ionization (HESI) and nano-ESI for the analysis of atmospheric aerosol samples in the negative ionization mode. In-source fragmentation tests were conducted and experiments involving sample desalting through solid-phase extraction (SPE) with a reversed phase functionalized polymeric sorbent and spiking samples with inorganic salt were performed. Both ionization sources showed specific advantages and disadvantages for the direct infusion analysis of atmospheric aerosol extracts. The mass spectra of aerosol samples analyzed using HESI contained a large number of high molecular weight homologues containing sulfur and nitrogen, suggesting that this source is prone to formation of salt adducts and noncovalent compounds in samples enriched with inorganic salts. Data from the same aerosol sample extracts analyzed using nanoelectrospray ionization (nano-ESI) show less adduct formation; however, a decrease in the number of homologues was observed, as well as loss of molecules at higher mass range, indicating that the nano-ESI source is more prone to ion suppression. Irrespective of ionization source, SPE pretreatment significantly improved ion recoveries for organic species with nonpolar and moderately polar functional groups, but lower recoveries were obtained for highly oxygenated molecules. Therefore, while SPE reduced in-source adduct formation, it also limited the range of compounds identified through a single analysis.
Collapse
Affiliation(s)
- I Kourtchev
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - P Szeto
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - I O'Connor
- School of Chemistry and Environmental Research Institute, University College Cork, College Road, Cork T12 K8AF, Ireland
| | - O A M Popoola
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - W Maenhaut
- Department of Chemistry, Ghent University, Krijgslaan 281, S12, Ghent 9000, Belgium
| | - J Wenger
- School of Chemistry and Environmental Research Institute, University College Cork, College Road, Cork T12 K8AF, Ireland
| | - M Kalberer
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.,Department of Environmental Sciences, University of Basel, Klingelbergstrasse 27, Basel 4056, Switzerland
| |
Collapse
|
29
|
Wang W, Bajic S, John B, Emerson DR. Numerical Simulation of Flow Field and Ion Transport for Different Ion Source Sampling Interfaces of a Mass Spectrometer. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:840-855. [PMID: 32134651 DOI: 10.1021/jasms.9b00103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Understanding ion transport mechanisms in the flow expansion section of the first vacuum region of a mass spectrometer (MS) with an atmospheric pressure ionization source is essential for optimizing the MS sampling interface design. In this study, numerical simulations of three types of ions in two different MS interface designs have been carried out. In contrast to previously reported numerical studies, nonequilibrium gas dynamics due to rarefied gas effects has been considered in modeling the flow expansion and a realistic space charge effect has been considered in a continuous ion injection mode. Numerical simulations reveal that a flat plate interface has a higher peak buffer gas velocity but a narrower zone of silence compared to the conical interface. Shock wave structures are clearly captured, and the Knudsen number distribution is displayed. Simulation results show that in the axial direction the buffer gas effect is much stronger than the electric force effect in the current configuration. The conical interface leads to both a strong ion acceleration in the zone of silence and a strong ion deceleration downstream. In the radial direction, both the electric force and buffer gas drag force play an important role. The conical interface introduces a relatively stronger ion focusing effect from the radial buffer gas effect and a stronger ion dispersion from the radial electric force than the flat plate interface. The net effect for the current configuration is an increase in ion losses for the conical interface. Nanoelectrospray ionization experiments were carried out to validate the ion transmission efficiency.
Collapse
Affiliation(s)
- Wei Wang
- STFC, Daresbury Laboratory, Warrington, Cheshire WA4 4AD, U.K
- Waters Corporation, Altrincham Rd, Wilmslow, Cheshire SK9 4AX, U.K
| | - Steve Bajic
- Waters Corporation, Altrincham Rd, Wilmslow, Cheshire SK9 4AX, U.K
| | - Benzi John
- STFC, Daresbury Laboratory, Warrington, Cheshire WA4 4AD, U.K
| | - David R Emerson
- STFC, Daresbury Laboratory, Warrington, Cheshire WA4 4AD, U.K
| |
Collapse
|
30
|
Yun BH, Guo J, Bellamri M, Turesky RJ. DNA adducts: Formation, biological effects, and new biospecimens for mass spectrometric measurements in humans. MASS SPECTROMETRY REVIEWS 2020; 39:55-82. [PMID: 29889312 PMCID: PMC6289887 DOI: 10.1002/mas.21570] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 04/25/2018] [Indexed: 05/18/2023]
Abstract
Hazardous chemicals in the environment and diet or their electrophilic metabolites can form adducts with genomic DNA, which can lead to mutations and the initiation of cancer. In addition, reactive intermediates can be generated in the body through oxidative stress and damage the genome. The identification and measurement of DNA adducts are required for understanding exposure and the causal role of a genotoxic chemical in cancer risk. Over the past three decades, 32 P-postlabeling, immunoassays, gas chromatography/mass spectrometry, and liquid chromatography/mass spectrometry (LC/MS) methods have been established to assess exposures to chemicals through measurements of DNA adducts. It is now possible to measure some DNA adducts in human biopsy samples, by LC/MS, with as little as several milligrams of tissue. In this review article, we highlight the formation and biological effects of DNA adducts, and highlight our advances in human biomonitoring by mass spectrometric analysis of formalin-fixed paraffin-embedded tissues, untapped biospecimens for carcinogen DNA adduct biomarker research.
Collapse
Affiliation(s)
- Byeong Hwa Yun
- Masonic Cancer Center and Department of Medicinal Chemistry, University of Minnesota, 2231 6 St. SE, Minneapolis, Minnesota, 55455, United States
| | - Jingshu Guo
- Masonic Cancer Center and Department of Medicinal Chemistry, University of Minnesota, 2231 6 St. SE, Minneapolis, Minnesota, 55455, United States
| | - Medjda Bellamri
- Masonic Cancer Center and Department of Medicinal Chemistry, University of Minnesota, 2231 6 St. SE, Minneapolis, Minnesota, 55455, United States
| | - Robert J. Turesky
- Masonic Cancer Center and Department of Medicinal Chemistry, University of Minnesota, 2231 6 St. SE, Minneapolis, Minnesota, 55455, United States
| |
Collapse
|
31
|
Wu Z, Bagarolo GI, Thoröe-Boveleth S, Jankowski J. "Lipidomics": Mass spectrometric and chemometric analyses of lipids. Adv Drug Deliv Rev 2020; 159:294-307. [PMID: 32553782 DOI: 10.1016/j.addr.2020.06.009] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 06/03/2020] [Accepted: 06/06/2020] [Indexed: 01/01/2023]
Abstract
Lipids are ubiquitous in the human organism and play essential roles as components of cell membranes and hormones, for energy storage or as mediators of cell signaling pathways. As crucial mediators of the human metabolism, lipids are also involved in metabolic diseases, cardiovascular and renal diseases, cancer and/or hepatological and neurological disorders. With rapidly growing evidence supporting the impact of lipids on both the genesis and progression of these diseases as well as patient wellbeing, the characterization of the human lipidome has gained high interest and importance in life sciences and clinical diagnostics within the last 15 years. This is mostly due to technically advanced molecular identification and quantification methods, mainly based on mass spectrometry. Mass spectrometry has become one of the most powerful tools for the identification of lipids. New lipidic mediators or biomarkers of diseases can be analysed by state-of-the art mass spectrometry techniques supported by sophisticated bioinformatics and biostatistics. The lipidomic approach has developed dramatically in the realm of life sciences and clinical diagnostics due to the available mass spectrometric methods and in particular due to the adaptation of biostatistical methods in recent years. Therefore, the current knowledge of lipid extraction methods, mass-spectrometric approaches, biostatistical data analysis, including workflows for the interpretation of lipidomic high-throughput data, are reviewed in this manuscript.
Collapse
Affiliation(s)
- Zhuojun Wu
- Institute for Molecular Cardiovascular Research, University Hospital RWTH Aachen, Aachen, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Giulia Ilaria Bagarolo
- Institute for Molecular Cardiovascular Research, University Hospital RWTH Aachen, Aachen, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Sven Thoröe-Boveleth
- Institute for Molecular Cardiovascular Research, University Hospital RWTH Aachen, Aachen, Pauwelsstraße 30, 52074 Aachen, Germany
| | - Joachim Jankowski
- Institute for Molecular Cardiovascular Research, University Hospital RWTH Aachen, Aachen, Pauwelsstraße 30, 52074 Aachen, Germany; School for Cardiovascular Diseases, Maastricht University, Universiteitssingel 50, Maastricht, The Netherlands.
| |
Collapse
|
32
|
Kang Y, Schneider BB, Bedford L, Covey TR. Design Characteristics to Eliminate the Need for Parameter Optimization in Nanoflow ESI-MS. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:2347-2357. [PMID: 31418126 DOI: 10.1007/s13361-019-02301-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/23/2019] [Accepted: 07/23/2019] [Indexed: 06/10/2023]
Abstract
The sampling efficiency in electrospray ionization-mass spectrometry (ESI-MS) can be improved by decreasing the liquid flow rate to the nanoflow regime, where it is possible to draw a large fraction of the ESI plume into the mass spectrometer. This mode of operation is typically more difficult than ESI-MS at higher flow rates because it requires careful optimization of a number of parameters to achieve optimal sampling efficiency. In this work, we screened the relative impact on signal intensity and spray stability of factors that included sprayer position, spray electrode protrusion, sprayer tip shape, spray angle relative to the MS inlet, nebulizer gas flow rate, ESI potential, and means for generating the electric field to initiate electrospray. Based on the screening results, we explore the possibility of providing fixed optimal values for many of the key source parameters to eliminate much of the tuning that is required for conventional nanoflow sources. This approach has potential to greatly simplify nanoflow ESI-MS, while providing optimized sensitivity, stability, and robustness, with decreased variability between analyses.
Collapse
Affiliation(s)
- Yang Kang
- SCIEX, 71 Four Valley Drive, Concord, Ontario, L4K 4V8, Canada.
| | | | - Leigh Bedford
- SCIEX, 71 Four Valley Drive, Concord, Ontario, L4K 4V8, Canada
| | - Thomas R Covey
- SCIEX, 71 Four Valley Drive, Concord, Ontario, L4K 4V8, Canada
| |
Collapse
|
33
|
Tang Y, Zhang JL. Recent developments in DNA adduct analysis using liquid chromatography coupled with mass spectrometry. J Sep Sci 2019; 43:31-55. [PMID: 31573133 DOI: 10.1002/jssc.201900737] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 09/04/2019] [Accepted: 09/27/2019] [Indexed: 12/15/2022]
Abstract
The formation of DNA adducts by genotoxic agents is an early event in cancer development, and it may lead to gene mutations, thereby initiating tumor development. The measurement of DNA adducts can provide critical information about the genotoxic potential of a chemical and its mechanism of carcinogenesis. In recent decades, liquid chromatography coupled with mass spectrometry has become the most important technique for analyzing DNA adducts. The improvements in resolution achievable with new chromatographic separation techniques coupled with the high specificity and sensitivity and wide dynamic range of new mass spectrometry systems have been used for both qualitative and quantitative analyses of DNA adducts. This review discusses the challenges in qualitative and quantitative analyses of DNA adducts by liquid chromatography coupled with mass spectrometry and highlights recent developments towards overcoming the limitations of liquid chromatography coupled with mass spectrometry methods. The key steps and new solutions, such as sample preparation, mass spectrometry fragmentation, and method validation, are summarized. In addition, the fundamental principles and latest advances in DNA adductomic approaches are reviewed.
Collapse
Affiliation(s)
- Yu Tang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, P. R. China
| | - Jin-Lan Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, P. R. China
| |
Collapse
|
34
|
Kulyk DS, Swiner DJ, Sahraeian T, Badu-Tawiah AK. Direct Mass Spectrometry Analysis of Complex Mixtures by Nanoelectrospray with Simultaneous Atmospheric Pressure Chemical Ionization and Electrophoretic Separation Capabilities. Anal Chem 2019; 91:11562-11568. [PMID: 31449396 DOI: 10.1021/acs.analchem.9b01456] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Accurate and rapid analysis of complex microsamples are challenging tasks in translational research. Nanoelectrospray ionization (nESI) is the method of choice for analyzing small sample volumes by mass spectrometry (MS), but this technique works well only for polar analytes. Herein, we describe a versatile dual noncontact nESI/nAPCI (nanoatmospheric pressure chemical ionization) source that allows simultaneous detection of both polar and nonpolar analytes in microliter quantities of samples under ambient conditions and without pretreatment. The same device can be activated to enable electrophoretic separation. The noncontact nESI/nAPCI MS platform was applied to analyze different samples, including high sensitive direct analysis of biofluids and the efficient detection of proteins in buffers with high concentration of nonvolatile salts. Excellent linearity, accuracy and limits of detection were achieved for compounds with different chemical properties in different matrices. The high sensitivity, universality, simplicity, and ease of operation make this MS technique promising for use in clinical and forensic applications.
Collapse
Affiliation(s)
- Dmytro S Kulyk
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Devin J Swiner
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Taghi Sahraeian
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Abraham K Badu-Tawiah
- Department of Chemistry and Biochemistry , The Ohio State University , Columbus , Ohio 43210 , United States
| |
Collapse
|
35
|
Rahman MM, Wu D, Chingin K, Xu W, Chen H. High ohmic resistor hyphenated gel loading tip nano-electrospray ionization source for mini mass spectrometer. Talanta 2019; 202:59-66. [PMID: 31171225 DOI: 10.1016/j.talanta.2019.04.052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 04/16/2019] [Accepted: 04/19/2019] [Indexed: 10/27/2022]
Abstract
The deployment of mini mass spectrometers on the field strongly demands efficient ionization sources that are easy-to-operate. Nano-electrospray (nESI) ion source has been widely used in the field of chemistry, biology, medicine, pharmaceutical industry, clinical assessment and forensic science. In this study, a high ohmic resistor hyphenated gel loading tip nESI source was coupled with our home developed mini mass spectrometer. This ionization source has the advantages of simple-in-design, disposable and low-in-cost, therefore it could be frequently used for analysis of aqueous samples without leading to cross contamination. Performances of the gel loading tip nESI emitter were similar to pulled glass capillary, and highly compatible for the analysis of biomolecule in aqueous solution. Different peptide and small molecules have been confirmed with a continuous atmospheric pressure-interfaced (CAPI) mini mass spectrometer. The corona discharge, which was usually observed at nESI emitter tip under high aqueous solvent conditions, resulting in low ion intensity, has been successfully quenched using a 10 GΩ resistor in both a pulled glass capillary and a gel loading tip as nESI emitter in this study. Compared with conventional ESI, the metal wire assisted gel loading tip facilitated loading and direct analysis of biological samples without sample pretreatment.
Collapse
Affiliation(s)
- Md Matiur Rahman
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Nanchang, 330013, China.
| | - Debo Wu
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Nanchang, 330013, China
| | - Konstantin Chingin
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Nanchang, 330013, China
| | - Wei Xu
- College of Information of Science, Shenzhen University, Shenzhen, 518060, China; School of Life Science, Beijing Institute of Technology, Beijing, 100081, China.
| | - Huanwen Chen
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Nanchang, 330013, China
| |
Collapse
|
36
|
Zhang F, Hong J, Xu W, Qu F. Straight nano-electrospray ionization and its coupling of mobility capillary electrophoresis to mass spectrometry. Talanta 2019; 206:120183. [PMID: 31514879 DOI: 10.1016/j.talanta.2019.120183] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/24/2019] [Accepted: 07/26/2019] [Indexed: 12/18/2022]
Abstract
Mobility capillary electrophoresis (MCE) was developed previously in our group, which has the capabilities of ion separation and biomolecule hydrodynamic radius analysis. The coupling of MCE with mass spectrometry (MS) would greatly improve complex sample identification capability as well as system detection sensitivity. In the present study, a simple and robust ionization source, named as straight nano-electrospray ionization (nanoESI) source was developed, which was applied to couple MCE with MS. A stainless-steel needle attached directly at the end of an MCE capillary was used as the nanoESI emitter, and the connection between this emitter to the liquid flow in the MCE separation channel was established through a liquid bridge. After optimization, this straight nanoESI source enhanced the ion signal intensity by ~10 times when compared with a commercial nanoESI source. The MCE-straight nanoESI-MS system was also characterized in terms of mixture separation and peptide hydrodynamic radius measurements. Compared to our previous work when a UV detector was used in a commercial Lumex CE system (model Capel 105 M, St. Petersburg, Russia), peptides with much lower concentrations could be analyzed (from ~1 mg/mL to ~20 μg/mL) in terms of radius measurement.
Collapse
Affiliation(s)
- Fei Zhang
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Jie Hong
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Wei Xu
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, China.
| | - Feng Qu
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, China.
| |
Collapse
|
37
|
Xu Z, Wu H, Tang Y, Xu W, Zhai Y. Electric modeling and characterization of pulsed high-voltage nanoelectrospray ionization sources by a miniature ion trap mass spectrometer. JOURNAL OF MASS SPECTROMETRY : JMS 2019; 54:583-591. [PMID: 30989769 DOI: 10.1002/jms.4361] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 04/01/2019] [Accepted: 04/08/2019] [Indexed: 06/09/2023]
Abstract
A better understanding of nanoelectrospray ionization (nano-ESI) would be beneficial in further improving the performances of nano-ESI. In this work, the pulsed high-voltage (HV) nano-ESI has been electrically modeled and then systematically characterized by both voltage-current and mass spectrometry measurements. First, the equivalent resistance of a nano-ESI source changes with respect to both emitter tip diameter and the HV applied. Increased voltage could improve both spray current and ionization efficiency of the pulsed HV nano-ESI. Compared with conventional DC HV method, a pulsed HV has less heating effect on the capillary tip and thus allowing the application of a much higher voltage onto a nano-ESI source. As a result, a pulsed HV nano-ESI could further boost the ionization efficiency of nano-ESI by employing even higher voltages than conventional DC nano-ESI sources.
Collapse
Affiliation(s)
- Zuqiang Xu
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Hanyan Wu
- Beijing Institute for Drug Control, Beijing, 102206, China
| | - Yang Tang
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Wei Xu
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| | - Yanbing Zhai
- School of Life Science, Beijing Institute of Technology, Beijing, 100081, China
| |
Collapse
|
38
|
Rahman M, Wu D, Chingin K. Direct Analysis of Aqueous Solutions and Untreated Biological Samples Using Nanoelectrospray Ionization Mass Spectrometry with Pipette Tip in Series with High-Ohmic Resistor as Ion Source. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:814-823. [PMID: 30834507 DOI: 10.1007/s13361-019-02142-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 12/28/2018] [Accepted: 01/21/2019] [Indexed: 06/09/2023]
Abstract
Commercially available disposable plastic pipette tip with the inner diameter of ca. 120 μm in series with a high-ohmic resistor (10 GΩ) was adapted as a low-cost alternative ion source for high-throughput nanoelectrospray mass spectrometry (nESI-MS) analysis of a variety of samples, especially aqueous solutions, without sample pretreatment. The use of high-ohmic resistor enabled the formation of stable electrospray of aqueous solutions at ambient conditions. In addition, corona discharge was avoided even with a high voltage applied. Quantitative analysis of vitamin B in water was successfully conducted by tip-ESI. The results exhibited a good linearity (R ˃ 0.9983), a low detection limit (0.25 ng/mL), and a wide dynamic response range (0.25-1000 ng/mL). Our study revealed that tip-ESI not only performed equally well to capillary nESI in terms of flow rate (˂ 100 nL/min), signal sensitivity, and sample consumption, but also offered a number of additional advantages, including better signal duration, tolerance to high analyte concentration (> 100 μg/mL) and high ionizing voltage (up to 6 kV), and obviation of tip clogging and corona discharge. High compatibility of tip-ESI with various kinds of samples (aqueous, viscous, solid, or bulk biological samples) makes it a promising tool for direct MS analysis.
Collapse
Affiliation(s)
- Matiur Rahman
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Nanchang, 330013, People's Republic of China
| | - Debo Wu
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Nanchang, 330013, People's Republic of China.
| | - Konstantin Chingin
- Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Nanchang, 330013, People's Republic of China
| |
Collapse
|
39
|
Tang Y, Harrington PB. Noninteger Root Transformations for Preprocessing Nanoelectrospray Ionization High-Resolution Mass Spectra for the Classification of Cannabis. Anal Chem 2019; 91:1328-1334. [PMID: 30565911 DOI: 10.1021/acs.analchem.8b03145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Typically, for measurements with a high dynamic range, the range is reduced by using the square root transform. By using noninteger roots coupled with systematic experimental design, improvements to the measurements may be obtained. The effect of using noninteger root transformation was evaluated using high-resolution mass spectrometry (HRMS) combined with nanoelectrospray ionization (Nano-ESI) to differentiate 23 samples of Cannabis. The mass spectra were evaluated and classified using different mass resolving powers and noninteger root transformations. Classification was achieved by super partial least-squares discriminant analysis (sPLS-DA), support vector machine (SVM), and SVM classification tree type entropy (SVMTreeH). The 2.5 root transformation gave the best overall performance at different resolving powers for chemical profiling from a multilevel factorial experimental design using 2 factors and more than 4 levels. Response surface modeling using a cubic polynomial model of the bootstrapped sPLS-DA average prediction accuracies yielded optima at 0.005 for resolving power and 2.3 for the root transformation. Root transformation is an important spectral preprocessing tool for decreasing the dynamic range so that the relative variance of smaller but more important features may be inflated. For the classification of Cannabis using Nano-ESI, the optimal ranges of root and resolution were broad. The chasing-the-optimum method has been introduced for refining the polynomial response surface model.
Collapse
Affiliation(s)
- Yue Tang
- Ohio University Center for Intelligent Chemical Instrumentation , Department of Chemistry and Biochemistry, Clippinger Laboratories , Athens , Ohio 45701-2979 , United States
| | - Peter B Harrington
- Ohio University Center for Intelligent Chemical Instrumentation , Department of Chemistry and Biochemistry, Clippinger Laboratories , Athens , Ohio 45701-2979 , United States
| |
Collapse
|
40
|
Improvement of electrospray stability in negative ion mode for nano-PGC-LC-MS glycoanalysis via post-column make-up flow. Glycoconj J 2018; 35:499-509. [DOI: 10.1007/s10719-018-9848-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 10/28/2018] [Accepted: 11/05/2018] [Indexed: 01/01/2023]
|
41
|
de Jesus J, Bunch J, Verbeck G, Webb RP, Costa C, Goodwin RJA, Bailey MJ. Application of Various Normalization Methods for Microscale Analysis of Tissues Using Direct Analyte Probed Nanoextraction. Anal Chem 2018; 90:12094-12100. [PMID: 30260213 DOI: 10.1021/acs.analchem.8b03016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Direct analyte probed nanoextraction (DAPNe) is a method of extracting material from a microscale region of a sample and provides the opportunity for detailed mass spectrometry analysis of extracted analytes from a small area. The technique has been shown to provide enhanced sensitivity compared with bulk analysis by selectively removing analytes from their matrix and has been applied for selective analysis of single cells and even single organelles. However, the quantitative capabilities of the technique are yet to be fully evaluated. In this study, various normalization techniques were investigated in order to improve the quantitative capabilities of the technique. Two methods of internal standard incorporation were applied to test substrates, which were designed to replicate biological sample matrices. Additionally, normalization to the extraction spot area and matrix compounds were investigated for suitability in situations when an internal standard is not available. The variability observed can be significantly reduced by using a sprayed internal standard and, in some cases, by normalizing to the extracted area.
Collapse
Affiliation(s)
- Janella de Jesus
- Department of Chemistry , University of Surrey , Guildford , Surrey GU2 7XH , United Kingdom.,The National Physical Laboratory , Teddington , Middlesex TW11 0LW , United Kingdom
| | - Josephine Bunch
- The National Physical Laboratory , Teddington , Middlesex TW11 0LW , United Kingdom
| | - Guido Verbeck
- University of North Texas , Denton , Texas 76203 , United States
| | - Roger P Webb
- University of Surrey Ion Beam Centre , Guildford , Surrey GU2 7XH , United Kingdom
| | - Catia Costa
- University of Surrey Ion Beam Centre , Guildford , Surrey GU2 7XH , United Kingdom
| | - Richard J A Goodwin
- Pathology Sciences, Drug Safety & Metabolism , IMED Biotech Unit, AstraZeneca , Cambridge , United Kingdom
| | - Melanie J Bailey
- Department of Chemistry , University of Surrey , Guildford , Surrey GU2 7XH , United Kingdom
| |
Collapse
|
42
|
Rahman MM, Chen LC. Analytical characteristics of nano-electrospray operated under super-atmospheric pressure. Anal Chim Acta 2018; 1021:78-84. [DOI: 10.1016/j.aca.2018.03.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Revised: 03/08/2018] [Accepted: 03/10/2018] [Indexed: 10/17/2022]
|
43
|
Keating JE, Glish GL. Dual Emitter Nano-Electrospray Ionization Coupled to Differential Ion Mobility Spectrometry-Mass Spectrometry for Shotgun Lipidomics. Anal Chem 2018; 90:9117-9124. [PMID: 29989393 DOI: 10.1021/acs.analchem.8b01528] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Current lipidomics workflows are centered around acquisition of large data sets followed by lengthy data processing. A dual nESI-DIMS-MS platform was developed to perform real-time relative quantification between samples, providing data required for biomarker discovery and validation more quickly than traditional ESI-MS approaches. Nanosprayer activity and DIMS compensation field settings were controlled by a LabVIEW program synced to the accumulation portion of the ion trap scan function, allowing for full integration of the platform with a commercial mass spectrometer. By comparing samples with short electrospray pulses rather than constant electrospray, the DIMS and MS performance is normalized within an experiment, as signals are compared between individual mass spectra (ms time scale) rather than individual experiments (min-hr time scale). The platform was validated with lipid standards and extracts from nitrogen-deprived microalgae. Dual nESI-DIMS requires minimal system modification and is compatible with all traditional ion activation techniques and mass analyzers, making it a versatile improvement to shotgun lipidomics workflows.
Collapse
Affiliation(s)
- James E Keating
- Department of Chemistry , The University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 United States
| | - Gary L Glish
- Department of Chemistry , The University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 United States
| |
Collapse
|
44
|
Characterization of a nanoflow sheath liquid interface and comparison to a sheath liquid and a sheathless porous-tip interface for CE-ESI-MS in positive and negative ionization. Anal Bioanal Chem 2018; 410:5265-5275. [DOI: 10.1007/s00216-018-1179-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 05/24/2018] [Accepted: 05/30/2018] [Indexed: 01/22/2023]
|
45
|
Ammonium hydroxide enhancing electrospray response and boosting sensitivity of bisphenol A and its analogs. Talanta 2018; 182:590-594. [DOI: 10.1016/j.talanta.2018.02.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 02/05/2018] [Accepted: 02/07/2018] [Indexed: 11/23/2022]
|
46
|
How can native mass spectrometry contribute to characterization of biomacromolecular higher-order structure and interactions? Methods 2018; 144:3-13. [PMID: 29704661 DOI: 10.1016/j.ymeth.2018.04.025] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 04/03/2018] [Accepted: 04/21/2018] [Indexed: 01/16/2023] Open
Abstract
Native mass spectrometry (MS) is an emerging approach for characterizing biomacromolecular structure and interactions under physiologically relevant conditions. In native MS measurement, intact macromolecules or macromolecular complexes are directly ionized from a non-denaturing solvent, and key noncovalent interactions that hold the complexes together can be preserved for MS analysis in the gas phase. This technique provides unique multi-level structural information such as conformational changes, stoichiometry, topology and dynamics, complementing conventional biophysical techniques. Despite the maturation of native MS and greatly expanded range of applications in recent decades, further dissemination is needed to make the community aware of such a technique. In this review, we attempt to provide an overview of the current body of knowledge regarding major aspects of native MS and explain how such technique contributes to the characterization of biomacromolecular higher-order structure and interactions.
Collapse
|
47
|
Bernier L, Pinfold H, Pauly M, Rauschenbach S, Reiss J. Gas Flow and Ion Transfer in Heated ESI Capillary Interfaces. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2018; 29:761-773. [PMID: 29468502 DOI: 10.1007/s13361-018-1895-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 01/10/2018] [Accepted: 01/16/2018] [Indexed: 06/08/2023]
Abstract
Transfer capillaries are the preferred means to transport ions, generated by electrospray ionization, from ambient conditions to vacuum. During the transfer of ions through the narrow, long tubes into vacuum, substantial losses are typical. However, recently it was demonstrated that these losses can be avoided altogether. To understand the experimental observation and provide a general model for the ion transport, here, we investigate the ion transport through capillaries by numerical simulation of interacting ions. The simulation encompasses all relevant factors, such as space charge, diffusion, gas flow, and heating. Special attention is paid to the influence of the gas flow on the transmission and especially the change imposed by heating. The gas flow is modeled by a one-dimensional gas dynamics description. A large number of ions are treated as point particles in this gas flow. This allows to investigate the influence of the capillary heating on the gas flow and by this on the ion transport. The results are compared with experimental findings. Graphical Abstract ᅟ.
Collapse
Affiliation(s)
| | | | - Matthias Pauly
- MPI f. Solid State Research, Stuttgart, Germany
- CNRS, Institut Charles Sadron, Université de Strasbourg, Strasbourg, France
| | - Stephan Rauschenbach
- MPI f. Solid State Research, Stuttgart, Germany
- Department of Chemistry, Oxford University, Oxford, UK
| | | |
Collapse
|
48
|
Conformational states during vinculin unlocking differentially regulate focal adhesion properties. Sci Rep 2018; 8:2693. [PMID: 29426917 PMCID: PMC5807537 DOI: 10.1038/s41598-018-21006-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 01/29/2018] [Indexed: 12/22/2022] Open
Abstract
Focal adhesions (FAs) are multi-protein complexes that connect the actin cytoskeleton to the extracellular matrix, via integrin receptors. The growth, stability and adhesive functionality of these structures are tightly regulated by mechanical stress, yet, despite the extensive characterization of the integrin adhesome, the detailed molecular mechanisms underlying FA mechanosensitivity are still unclear. Besides talin, another key candidate for regulating FA-associated mechanosensing, is vinculin, a prominent FA component, which possesses either closed (“auto-inhibited”) or open (“active”) conformation. A direct experimental demonstration, however, of the conformational transition between the two states is still absent. In this study, we combined multiple structural and biological approaches to probe the transition from the auto-inhibited to the active conformation, and determine its effects on FA structure and dynamics. We further show that the transition from a closed to an open conformation requires two sequential steps that can differentially regulate FA growth and stability.
Collapse
|
49
|
Abstract
Experimental methods for the characterization of protein complexes have been instrumental in achieving our current understanding of the protein universe and continue to progress with each year that passes. In this chapter, we review some of the most important tools and techniques in the field, covering the important points in X-ray crystallography, cryo-electron microscopy, NMR spectroscopy, and mass spectrometry. Novel developments are making it possible to study large protein complexes at near-atomic resolutions, and we also now have the ability to study the dynamics and assembly pathways of protein complexes across a range of sizes.
Collapse
Affiliation(s)
- Jonathan N Wells
- MRC Human Genetics Unit, Institute of Genetics & Molecular Medicine, University of Edinburgh, Edinburgh, UK.
| | - Joseph A Marsh
- MRC Human Genetics Unit, Institute of Genetics & Molecular Medicine, University of Edinburgh, Edinburgh, UK
| |
Collapse
|
50
|
Hollerbach A, Logsdon D, Iyer K, Li A, Schaber JA, Graham Cooks R. Sizing sub-diffraction limit electrosprayed droplets by structured illumination microscopy. Analyst 2018; 143:232-240. [PMID: 29138765 DOI: 10.1039/c7an01278k] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Electrosprayed droplets are widely studied for their role in the formation of ions at atmospheric pressure.
Collapse
Affiliation(s)
| | - David Logsdon
- Chemistry Department
- Purdue University
- West Lafayette
- USA
| | - Kiran Iyer
- Chemistry Department
- Purdue University
- West Lafayette
- USA
| | - Anyin Li
- Chemistry Department
- Purdue University
- West Lafayette
- USA
| | - J. Andy Schaber
- Bioscience Imaging Facility
- Bindley Bioscience Center
- Purdue University
- West Lafayette
- USA
| | | |
Collapse
|