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Gross JH. Matrix-Assisted Laser Desorption/Ionization. Mass Spectrom (Tokyo) 2017. [DOI: 10.1007/978-3-319-54398-7_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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2
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Manard BT, Jones SMH, Marcus RK. Capillary-channeled polymer (C-CP) fibers for the rapid extraction of proteins from urine matrices prior to detection with MALDI-MS. Proteomics Clin Appl 2015; 9:522-30. [PMID: 25450308 DOI: 10.1002/prca.201400081] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 10/10/2014] [Accepted: 11/25/2014] [Indexed: 11/07/2022]
Abstract
PURPOSE While MS is a powerful tool for biomarker determinations, the high salt content and the small molecules present in urine poses incredible challenges. Separation/extraction methods must be employed for the isolation of target species at relevant concentrations. Micropipette tips packed with capillary-channeled polymer (C-CP) fibers are employed for the SPE of proteins from a synthetic and a certified urine matrix. EXPERIMENTAL DESIGN Extractions are performed utilizing a very simple centrifugation method to spin-down species through the C-CP fiber tips. Proteins adsorb to the hydrophobic polypropylene fibers and are eluted in a solvent suitable for MALDI-MS analysis. Figures of merit are determined for representative compounds β2-microglobulin, retinol binding protein, and transferrin. RESULTS The optimum protein processing included a 100 μL aqueous rinse and an elution solvent composition was 10 μL of 55:45 ACN:water (with triflouroacetic acid). MALDI-MS responses for the target proteins are improved from nondetectable levels to eventually yield LOD ranging from 5 to 180 nM in 1 μL aliquots. CONCLUSION AND CLINICAL RELEVANCE C-CP fiber tips offer a plethora of advantages including low materials costs, high throughput, microvolume processing, and the determination of sub-nanogram quantities of analyte; allowing determination of biomarkers that are otherwise undetectable in urine matrices.
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Affiliation(s)
| | - Sarah M H Jones
- Department of Chemistry, Clemson University, Clemson, SC, USA
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3
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Mitrovic B, Eastwood S, Wong V, Dyer D, Kinsel G, Scott C. Peptide/protein separation with cationic polymer brush nanosponges for MALDI-MS analysis. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:696-700. [PMID: 23244629 PMCID: PMC3632665 DOI: 10.1021/la3033995] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
A cationic polymer nanobrush was synthesized, attached to a MALDI target, and used for the fractionation of peptides and proteins based on their pI, prior to analysis by MALDI-MS. The cationic polymer nanobrush was synthesized on a gold substrate by AIBN photoinitiated polymerization, using a 70:30 ratio of 2-aminoethyl methacrylate hydrochloride (AEMA):N-isopropylacrylamide (NIPAAM). This brush showed selectivity for adsorption of acidic peptides and proteins and allowed fractionation of simple two-component mixtures to be completed in less than 10 min. The brush-adsorbed biomolecules were recovered by treating the nanobrush with ammonium hydroxide, which effectively collapsed the brush, thereby releasing the trapped compounds for MALDI MS analysis. These results demonstrate that nanobrush can serve as a convenient platform for rapid fractionation of biomolecules prior to analysis by MALDI-MS.
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4
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Adler B, Laurell T, Ekström S. Optimizing nanovial outlet designs for improved solid-phase extraction in the integrated selective enrichment target-ISET. Electrophoresis 2012; 33:3143-50. [DOI: 10.1002/elps.201200134] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 04/19/2012] [Accepted: 04/23/2012] [Indexed: 01/12/2023]
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5
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Manard BT, Marcus RK. Capillary-channeled polymer (C-CP) fibers as a stationary phase for sample clean-up of protein solutions for matrix-assisted laser/desorption ionization mass spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2012; 23:1419-1423. [PMID: 22653465 DOI: 10.1007/s13361-012-0399-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 04/20/2012] [Accepted: 04/20/2012] [Indexed: 06/01/2023]
Abstract
Capillary-channeled polymer (C-CP) fibers are employed in a micropipette tip format to affect a stationary phase for the solid phase extraction (SPE) of proteins from buffer solutions prior to MALDI-MS analysis. Proteins readily adsorb to the polypropylene (PP) C-CP fibers while buffer species are easily washed off the tips using DI-H(2)O. Elution of the solutes is achieved with an aliquot of 50:50 ACN:H(2)O, which is compatible with the subsequent spotting on the MALDI target with the matrix solution. Lysozyme and cytochrome c are used as test species, with a primary buffer composition of 100 mM Tris-HCl. In this case, direct MALDI-MS produces no discernible protein signals. SPE on the C-CP fibers yields high fidelity mass spectra for 1 μL sample volumes. Limits of detection for cytochrome c in 100 mM Tris-HCl are on the order of 40 nM. Extraction of cytochrome c from buffer concentrations of up to 1 M Tris-HCl, provides signal recoveries that are suppressed by only ~50% versus neat protein solutions. Finally, extraction of 3.1 μM cytochrome c from a synthetic urine matrix exhibits excellent recovery.
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Affiliation(s)
- Benjamin T Manard
- Department of Chemistry, Biosystems Research Complex, Clemson University, Clemson, SC 29633, USA
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6
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Mandal MK, Chen LC, Yu Z, Nonami H, Erra-Balsells R, Hiraoka K. Detection of protein from detergent solutions by probe electrospray ionization mass spectrometry (PESI-MS). JOURNAL OF MASS SPECTROMETRY : JMS 2011; 46:967-975. [PMID: 22012662 DOI: 10.1002/jms.1977] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Detergents are necessarily used for different extraction protocols of proteins from biological cells or tissues. After the extraction, elimination of detergent is necessary for the better performance of electrospray ionization mass spectrometry (ESI-MS). Elimination of detergents is laborious and time-consuming, and also sample loss may be unavoidable. Probe electrospray ionization (PESI) developed in our laboratory has been found to be tolerant to the presence of salts and buffers in sample solutions. In this report, it was examined whether PESI is applicable to the sample solutions that contain high-concentration of detergents. It was found that PESI is highly tolerant to the presence of sodium dodecyl sulphate, cetyl trimethylamminium bromide, Triton X100 and 3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulfonate compared with conventional ESI and nanoESI. Therefore, PESI can be a potential analytical tool for direct analysis of protein extracts and digests containing high-concentration detergents.
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Affiliation(s)
- Mridul Kanti Mandal
- Clean Energy Research Center, University of Yamanashi, Kofu, Yamanashi, Japan
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7
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Detection of peptides in high concentration of salts by electrospray droplet impact/secondary ion mass spectrometry. SURF INTERFACE ANAL 2011. [DOI: 10.1002/sia.3719] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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8
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Gross JH. Matrix-Assisted Laser Desorption/Ionization. Mass Spectrom (Tokyo) 2011. [DOI: 10.1007/978-3-642-10711-5_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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9
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Interferences and contaminants encountered in modern mass spectrometry. Anal Chim Acta 2008; 627:71-81. [PMID: 18790129 DOI: 10.1016/j.aca.2008.04.043] [Citation(s) in RCA: 419] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2008] [Revised: 04/14/2008] [Accepted: 04/16/2008] [Indexed: 12/26/2022]
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10
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Jia W, Wu H, Lu H, Li N, Zhang Y, Cai R, Yang P. Rapid and automatic on-plate desalting protocol for MALDI-MS: using imprinted hydrophobic polymer template. Proteomics 2007; 7:2497-506. [PMID: 17610205 DOI: 10.1002/pmic.200601029] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A novel protocol of rapid and automatic on-plate desalting (OPD) and peptide concentration for 2-DE-MALDI-MS has been developed by the approach of templating the hydrophobic polymer solution over Kapton-etched mask. For the template technique, small hydrophobic polymer [linear poly(methyl methacrylate) (PMMA), PMMA derivatized with fullerene-C60 (PMMA-C60), linear polystyrene (PSt), or PSt derivatized with fullerene-C60 (PSt-C60)] spots (990 microm od) are patterned at the centers of stainless MALDI plate wells (1400 microm id). Tryptic-peptide solution with no predesalting was dropped onto the central hydrophobic spots, resulting in a concentration of proteolytic peptides on the hydrophobic polymer surface with a reduced spot size. The dried peptide layer was then covered subsequently with over-volume matrix solution, causing the removal of redissolved salts from the spot center to the spot edge by means of a natural "outward flow." The proposed OPD protocol exhibited a dramatic enhancement in S/N up to 850 for 14 fmol BSA digests in the coexistence of 100 mM salts, compared with barely detectable peaks in ordinary way. This analysis has shown that the success rate of identification was increased by two-fold for low abundance proteins in the human liver tissue with no need for the conventional ZipPlate desalting strategy.
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Affiliation(s)
- Weitao Jia
- Department of Chemistry, Fudan University, Shanghai, Peoples Republic of China
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11
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Zhang Y, Fang J, Kuang Y, Guo X, Lu H, Yang P. Wash-free in-situ self-desalting and peptide enrichment by block copolymer analyzed with MALDI-TOFMS. Chem Commun (Camb) 2007:4468-70. [PMID: 17971958 DOI: 10.1039/b710741b] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel technique of simultaneous peptide enrichment and wash-free in-situ self-desalting for MALDI analysis is reported, where a newly synthesized block copolymer with a microphase-separated configuration is applied to embed salts with its hydrophilic domain of poly(ethylene oxide) and concentrate peptides with its hydrophobic domain of polysulfone.
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Affiliation(s)
- Ying Zhang
- Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, Shanghai 200433, PR China
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12
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Zhao C, O'Connor PB. Removal of polyethylene glycols from protein samples using titanium dioxide. Anal Biochem 2007; 365:283-5. [PMID: 17462581 PMCID: PMC1949484 DOI: 10.1016/j.ab.2007.03.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Revised: 02/14/2007] [Accepted: 03/20/2007] [Indexed: 11/26/2022]
Affiliation(s)
- Cheng Zhao
- Mass Spectrometry Resource, Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118, USA
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13
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McComb ME, Perlman DH, Huang H, Costello CE. Evaluation of an on-target sample preparation system for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry in conjunction with normal-flow peptide high-performance liquid chromatography for peptide mass fingerprint analyses. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2007; 21:44-58. [PMID: 17133622 DOI: 10.1002/rcm.2805] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Large-scale mass spectrometry (MS)-based proteomic analyses require high-throughput sample preparation techniques due to the increasing numbers of samples that make up a typical proteomics experiment. Moreover, extensive sample pre-treatment steps are necessary prior to MS acquisition for even the most rapid and robust MS-based proteomics methodology, matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS followed by peptide mass fingerprinting (PMF) analysis. These include sample purification and fractionation, removal of digestion buffers or solvents, and spotting of sample with matrix onto the MALDI target. These multiple steps of time-consuming sample handling can result in high overall analysis costs and the likelihood of sample contamination and loss. In order to overcome some of these limitations in sample processing, we have investigated the use of a novel, simple, inexpensive 96-well elastomeric array that affixes to a MALDI target to create an on-target 96-well plate that accommodates a high solution volume (ca. 200 microL), thereby enabling the on-target processing of samples for MALDI-TOFMS. We explored several factors that influence MALDI sample preparation: type of matrix, solution volume, solution organic composition, solution drying rates and matrix/analyte co-crystallization methods. We also investigated the use of the 96-well elastomeric device for coupling MALDI-TOFMS analysis directly to high flow rate (1 mL/min) reversed-phase (rp)-HPLC. By developing an optimized, robust sample preparation protocol, we were able to obtain mass spectra with a high signal-to-noise ratio from peptide standards present at the 50-fmol level in large starting volumes of solution. PMF analyses were possible from 1-pmol and 500-fmol protein-digest standards. Coupling the device to high-flow HPLC (750 microL/min) yielded a robust and semi-automated means to obtain enhanced MALDI-TOFMS data at 500 ng of protein digest. These methodologies developed for this simple, on-target, elastomeric device show promise for streamlining the sample preparation process from HPLC to MALDI-MS.
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Affiliation(s)
- Mark E McComb
- Cardiovascular Proteomics Center, Boston University School of Medicine, Boston, MA 02118-2646, USA.
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14
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Tyan YC, Guo HR, Liu CY, Liao PC. Proteomic profiling of human urinary proteome using nano-high performance liquid chromatography/electrospray ionization tandem mass spectrometry. Anal Chim Acta 2006; 579:158-76. [PMID: 17723740 DOI: 10.1016/j.aca.2006.07.033] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2006] [Revised: 07/13/2006] [Accepted: 07/17/2006] [Indexed: 10/24/2022]
Abstract
Urine, a blood filtrate produced by the urinary system, is an ideal bio-sample and a rich source of biomarkers for diagnostic information. Many components in urine are useful in clinical diagnosis, and urinary proteins can be strong indication for many diseases such as proteinuria, kidney, bladder and urinary tract diseases. To enhance our understanding of urinary proteome, the urine proteins were prepared by different sample cleanup preparation methods and identified by nano-high performance liquid chromatography electrospray ionization tandem mass spectrometry followed by peptide fragmentation pattern. The experimental results demonstrated that a total of 2283 peptides, corresponding to 311 unique proteins, were identified from human urine samples, in which 104 proteins with higher confidence levels. The present study was designed to establish optimal techniques to create a proteomic map of normal urinary proteins. Also, a discussion of novel approaches to urine protein cleanup and constituents is given.
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Affiliation(s)
- Yu-Chang Tyan
- Department of Environmental and Occupational Health, College of Medicine, National Cheng Kung University, 138 Sheng-Li Road, Tainan, Taiwan
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15
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Xu S, Zhou H, Pan C, Fu Y, Zhang Y, Li X, Ye M, Zou H. Iminodiacetic acid derivatized porous silicon as a matrix support for sample pretreatment and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2006; 20:1769-75. [PMID: 16676319 DOI: 10.1002/rcm.2493] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Iminodiacetic acid (IDA)-1,2-epoxy-9-decene has been synthesized and covalently linked to the surface of porous silicon wafer through a photochemical reaction. The negatively charged carboxylic acid groups on the porous silicon wafer are capable of binding oppositely charged species from sample solutions through electrostatic interactions. This allows the removal of contaminants prior to matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) by simply washing the porous silicon surface. The carboxylic acid end groups on porous silicon can be used to selectively bind and concentrate target species in sample solutions. Furthermore, Fe(3+)-IDA-derivatized porous silicon was prepared to specifically and effectively concentrate phosphopeptides from the tryptic digests of phosphoproteins, followed by MALDI-MS analysis.
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Affiliation(s)
- Songyun Xu
- National Chromatographic R & A Center, Dalian Institute of Chemical Physics, The Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, Dalian 116011, China
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16
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Wang Y, Xia X, Guo Y. Porous anodic alumina membrane as a sample support for MALDI-TOF MS analysis of salt-containing proteins. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2005; 16:1488-1492. [PMID: 16023364 DOI: 10.1016/j.jasms.2005.04.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2005] [Revised: 04/25/2005] [Accepted: 04/27/2005] [Indexed: 05/03/2023]
Abstract
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometric (MALDI-TOF MS) analysis of proteins in salt-containing solution was performed for the first time using porous anodic alumina (PAA) membrane as sample support. The resulting spectral quality of proteins under standard sample preparation conditions was superior to that of normal metal sample stages. Analysis of phosphate-doped protein solutions indicated that porous anodic alumina membranes as a target yielded better results than a metallic target for salt-containing solutions. Because of the biocompatibility of the PAA, proteins can be adsorbed on the PAA and thus a washing process can be introduced to remove the salts from the PAA target before MS analysis. This desalting step significantly enhanced spectral quality, and better signal-to-noise ratios were obtained. The present technique is promising for proteomics research.
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Affiliation(s)
- Yuebo Wang
- Key Laboratory of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, 210093, Nanjing, People's Republic of China
- Shanghai Mass Spectrometry Center, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 200032, Shanghai, People's Republic of China
| | - Xinghua Xia
- Key Laboratory of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, 210093, Nanjing, People's Republic of China.
| | - Yinlong Guo
- Shanghai Mass Spectrometry Center, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 200032, Shanghai, People's Republic of China.
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17
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Chung WJ, Kim MS, Cho S, Park SS, Kim JH, Kim YK, Kim BG, Lee YS. Microaffinity purification of proteins based on photolytic elution: Toward an efficient microbead affinity chromatography on a chip. Electrophoresis 2005; 26:694-702. [PMID: 15690422 DOI: 10.1002/elps.200410005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A bead affinity chromatography system, which was based on the photolytic elution method, was integrated into a glass-silicon microchip to purify specific target proteins. CutiCore beads, which were coupled with a photo-cleavable ligand, such as biotin and an RNA aptamer, were introduced into a filter chamber in the microchip. The protein mixture containing target protein labeled with fluorescein isothiocyanate (FITC) was then passed through the packed affinity beads in the microchamber by pressure-driven flow. During the process, the adsorbed protein on the bead was monitored by fluorescence. The concentrated target protein on the affinity bead was released by simple irradiation with UV light at a wavelength of 360 nm, and subsequently eluted with the phosphate buffer flow. The eluted target protein was quantitatively detected via the fluorescence intensity measurements at the downstream of the capillary connected to the outlet of the microchip. The microaffinity purification allowed for a successful method for the identification of specific target proteins from a protein mixture. In addition, the feasibility of this system for use as a diagnosis chip was demonstrated.
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Affiliation(s)
- Woo-Jae Chung
- School of Chemical Engineering, Seoul National University, Kwanak-Gu, Seoul, Korea
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18
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Salplachta J, Rehulka P, Chmelík J. Identification of proteins by combination of size-exclusion chromatography with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and comparison of some desalting procedures for both intact proteins and their tryptic digests. JOURNAL OF MASS SPECTROMETRY : JMS 2004; 39:1395-1401. [PMID: 15578741 DOI: 10.1002/jms.700] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Separation of a protein mixture by size-exclusion chromatography (SEC) was combined with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). Identification of proteins in the collected fractions was performed both as intact proteins by MALDI-TOFMS and using peptide mass fingerprinting (PMF) after their digestion with trypsin. The presence of salts mostly disturbs the MALDI-TOFMS signal and, therefore, proper purification or desalting procedures must be employed. Four desalting procedures (desalting column packed with Sephadex G-100, on-target washing, centrifugal filter devices and ZipTip C(18)) for purification of fractions of proteins separated by SEC and their tryptic digests prior to determination of their exact molecular masses by MALDI-TOFMS were compared. In the case of intact proteins, the experiments showed that the best desalting procedures are the use of ZipTip C(18) pipette tips and Ultrafree CL centrifugal filter devices. The peptide digests can be purified by using ZipTip C(18) pipette tips or on-target washing when both of these procedures provide similar results. On-target washing can be used as a simple procedure to improve the mass spectra of salt-containing samples. Analyses of the droplets collected after the on-target washing show losses of sample and matrix caused by dissolution of these compounds during this procedure. Further, it was found that protein identification based on PMF is more sensitive than analyses of intact proteins and that multiple on-target washing is very advantageous for analyses of peptide mixtures with a high content of salts.
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Affiliation(s)
- Jirí Salplachta
- Institute of Analytical Chemistry, Academy of Sciences of the Czech Republic, Veverí 97, 611 42 Brno, Czech Republic
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19
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Xu Y, Bruening ML, Watson JT. Non-specific, on-probe cleanup methods for MALDI-MS samples. MASS SPECTROMETRY REVIEWS 2003; 22:429-440. [PMID: 14528495 DOI: 10.1002/mas.10064] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
High concentrations of contaminants such as salts and surfactants are often present in biological samples to solubilize or stabilize analytes such as proteins. Unfortunately, the presence of those contaminants often precludes direct analysis by MALDI-MS. Selective adsorption of analytes directly on modified MALDI probes, followed by rinsing to remove contaminants, overcomes this problem. This review focuses on various modifications of MALDI probes to allow the adsorption of proteins and DNA, even in a large excess of salt or surfactant. Interfaces deposited on the MALDI probes to adsorb analytes include films of commercial polymers, thin layers of matrix crystals, self-assembled monolayers, and ultrathin polymer films. Hydrophobic and ionic interactions both effect analyte adsorption on those interfaces, and patterned interfaces allow the concentration and purification of analyte molecules.
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Affiliation(s)
- Yingda Xu
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
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20
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Shen J, Buko A. Rapid identification of proteins in polyethylene glycol-containing samples using capillary electrophoresis electrospray mass spectrometry. Anal Biochem 2002; 311:80-3. [PMID: 12441156 DOI: 10.1016/s0003-2697(02)00381-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Jianwei Shen
- Department of Structural Chemistry, GPRD, Abbott Laboratories, Abbott Park, IL 60064, USA.
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21
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Rubakhin SS, Page JS, Monroe BR, Sweedler JV. Analysis of cellular release using capillary electrophoresis and matrix assisted laser desorption/ionization-time of flight-mass spectrometry. Electrophoresis 2001; 22:3752-8. [PMID: 11699914 DOI: 10.1002/1522-2683(200109)22:17<3752::aid-elps3752>3.0.co;2-h] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In order to increase our understanding of the mechanisms of learning and memory in the central nervous system, it is necessary to know the neurotransmitters and neuromodulators used in the specific neuronal circuits under study. Methods have been developed to identify the peptides released from single neurons and neuronal clusters from the common neuronal model Aplysia californica. Specifically, solid-phase extraction (SPE), capillary electrophoresis (CE) and matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) are combined for profiling neuropeptide releasates. A variety of combinations of SPE and CE were coupled off-line with MALDI-TOF-MS to reduce the high physiological salts, to concentrate the analytes, and to reduce the complexity of the mass spectra using separation. With these protocols, peptides and proteins up to 11000 Da were detected in releasates, offering a much wider mass range compared to direct MALDI analysis of the same releasates. A number of expected and unknown neuropeptides, including egg-laying hormone (ELH) and the partially processed delta/gamma-bag cell peptide were observed in the SPE-treated releasates from a single Aplysia-cultured bag cell neuron. However, by adding a CE separation after the SPE step preceding off-line MALDI-TOF-MS detection, the most complete neuropeptide profiles were obtained.
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Affiliation(s)
- S S Rubakhin
- Department of Chemistry and the Beckman Institute, University of Illinois, Urbana 61801, USA
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22
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Gilar M, Bouvier ES, Compton BJ. Advances in sample preparation in electromigration, chromatographic and mass spectrometric separation methods. J Chromatogr A 2001; 909:111-35. [PMID: 11269513 DOI: 10.1016/s0021-9673(00)01108-0] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The quality of sample preparation is a key factor in determining the success of analysis. While analysis of pharmaceutically important compounds in biological matrixes has driven forward the development of sample clean-up procedures in last 20 years, today's chemists face an additional challenge: sample preparation and analysis of complex biochemical samples for characterization of genotypic or phenotypic information contained in DNA and proteins. This review focuses on various sample pretreatment methods designed to meet the requirements for the analysis of biopolymers and small drugs in complex matrices. We discuss the advances in development of solid-phase extraction (SPE) sorbents, on-line SPE, membrane-based sample preparation, and sample clean-up of biopolymers prior to their analysis by mass spectrometry.
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Affiliation(s)
- M Gilar
- Waters Corp., Milford, MA 01757, USA.
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Abstract
Mass spectrometry (MS) has become the technique of choice to identify proteins. This has been largely accomplished by the combination of high-resolution two-dimensional (2-D) gel separation with robotic sample preparation, automated MS measurement, data analysis, and database query. Developments during the last five years in MS associated with protein gel separation are reviewed.
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Affiliation(s)
- H W Lahm
- F. Hoffmann-LaRoche Ltd., Pharmaceutical Research, Roche Genetics, Basel, Switzerland.
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Abstract
The overall history and recent advances in surface enhanced laser desorption/ionization-time of flight-mass spectrometry (SELDI-TOF-MS) technology is reviewed herein. Fundamentals of SELDI-TOF analysis are presented while drawing comparisons with other laser-based mass spectrometry techniques. The application of SELDI-TOF-MS to functional genomics and biomarker discovery is discussed and exemplified by elucidating a biomarker candidate for prostatic carcinoma. Finally, a short discussion regarding future SELDI requirements and developments is supplied.
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Affiliation(s)
- M Merchant
- Ciphergen Biosystems, Inc., Palo Alto, CA 94306, USA
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