1
|
Guo Z, Chen Y, Wang S, Pang J, Liu Z. Dendritic Mesoporous Silica Nanospheres: Toward the Ultimate Minimum Particle Size for Ultraefficient Liquid Chromatographic Separation. ACS APPLIED MATERIALS & INTERFACES 2021; 13:22970-22977. [PMID: 33956437 DOI: 10.1021/acsami.1c03985] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Use of smaller particle size of packing materials in liquid chromatography leads to faster separation and higher efficiency. This basic law has driven the evolution of packing materials for several generations. However, the use of nanoscale packing materials has been severely hampered by extremely high back pressure. Here, we report a new possibility of solving this issue via introducing novel nanomaterials with highly favorable structures. n-Octyl-modified monodispersed dendritic mesoporous silica nanospheres (DMSNs) with an unprecedentedly small diameter (ca. 170 nm) and appropriate pore size (5.6 nm) were controllably synthesized and demonstrated to be a practically applicable packing material offering ultrahigh efficiency. The center-radial centrosymmetric mesopore channels significantly improved the permeability of packed capillaries, enabling column packing and capillary electrochromatographic separation on regular instruments. Due to the unique morphology, very tiny particle size, and highly uniform packing, the packed column exhibited ultrahigh efficiency up to 3 500 000 plates/m. Powerful separation capability was demonstrated with glycan profiling of cancerous and normal cells, which revealed that cancerous cells exhibited characteristic N-glycans. Because DMSNs with tunable particle size and mesopores can be controllably prepared, DMSNs hold great potential to be a new record toward the ultimate generation of packing materials for ultraefficient liquid chromatographic separation.
Collapse
Affiliation(s)
- Zhanchen Guo
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Yang Chen
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Shuangshou Wang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Jilei Pang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Zhen Liu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| |
Collapse
|
2
|
Rohleder D, Vana P. Near-Infrared-Triggered Photothermal Aggregation of Polymer-Grafted Gold Nanorods in a Simulated Blood Fluid. Biomacromolecules 2021; 22:1614-1624. [PMID: 33689319 DOI: 10.1021/acs.biomac.1c00077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Gold nanorods were decorated with thermoresponsive copolymers of tailored architecture and constructed from N-isopropyl acrylamide and acrylamide. The copolymers were prepared via reversible addition-fragmentation chain transfer polymerization (RAFT) and immobilized on the gold nanorod surface taking advantage of the aurophilicity of its inherently formed trithiocarbonate groups. The topology as well as the average molecular weight of the copolymers was altered using either a monofunctional or 3-arm star RAFT agent. Two-dimensional arrays of the self-assembled core-shell nanostructures were fabricated by drop-casting showing tunable interparticle spacings. In a simulated blood fluid, the lower critical solution temperature of the nanohybrids could be modified over a significant temperature range around body temperature by adjusting the copolymer composition, the architecture, and/or the size of the polymer. The intrinsic photothermal properties of the gold nanorods were utilized to trigger particle aggregation by irradiation at 808 nm in the optical window of human tissues. In effect, a new nanohybrid system with remotely controllable aggregation via an external NIR-light stimulus for nanomedical applications was developed.
Collapse
Affiliation(s)
- Darius Rohleder
- Institute of Physical Chemistry, Georg-August-University Göttingen, Tammannstr. 6, Göttingen 37077, Germany
| | - Philipp Vana
- Institute of Physical Chemistry, Georg-August-University Göttingen, Tammannstr. 6, Göttingen 37077, Germany
| |
Collapse
|
3
|
Wang L, Li Y, Chen D, Chen DDY. Electrospray ionization stability and concentration sensitivity in capillary electrophoresis-mass spectrometry using a flow-through microvial interface. Electrophoresis 2021; 42:360-368. [PMID: 33345341 DOI: 10.1002/elps.202000239] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 11/25/2020] [Accepted: 12/17/2020] [Indexed: 01/02/2023]
Abstract
Concentration sensitivity is a key performance indicator for analytical techniques including for capillary electrophoresis-mass spectrometry (CE-MS) with electrospray ionization (ESI). In this study, a flow-through microvial interface was used to couple CE with MS and improve the ESI stability and detection sensitivity. By infusing a peptide mixture through the interface into an MS detector at a typical flow rate for CE-MS analysis, the spatial region near the interface was mapped for MS signal intensity. When the sprayer tip was within a 6 × 6.5 × 5 mm region in front of the MS inlet, the ESI was stable with no significant loss of signal intensity for ions with m/z 239. Finite element simulations showed that the average electric field strength at the emitter tip did not change significantly with minor changes in emitter tip location. Experiments were conducted with four different mass spectrometer platforms coupled to CE via the flow-through microvial interface. Key performance indicators, that is, limit of detection (LOD) and linearity of calibration curves were measured for nine amino acids and five peptides. Inter- and intraday reproducibility were also tested. The results were shown to be suitable for quantification when internal standards were used.
Collapse
Affiliation(s)
- Lingyu Wang
- Department of Chemistry, University of British Columbia, Vancouver, V6T 1Z1, Canada
| | - Yueyang Li
- Department of Chemistry, University of British Columbia, Vancouver, V6T 1Z1, Canada
| | - Dazhou Chen
- Department of Analytical Chemistry and Stoichiometry, National Institution of Metrology, Beijing, P. R. China
| | - David Da Yong Chen
- Department of Chemistry, University of British Columbia, Vancouver, V6T 1Z1, Canada
| |
Collapse
|
4
|
Identification of intracellular cadmium transformation in HepG2 and MCF-7 cells. Talanta 2020; 218:121065. [PMID: 32797863 DOI: 10.1016/j.talanta.2020.121065] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 04/17/2020] [Accepted: 04/19/2020] [Indexed: 01/14/2023]
Abstract
It is of significance to elucidate or understand the intracellular transformation & migration behaviors of heavy metals in specific cells. Herein, we report the fast and efficient separation of cadmium-metallothioneins (Cd-MTs) and Cd2+in cell lysate by a short column capillary electrophoresis (SC-CE), followed by coupling with inductively coupled plasma mass spectrometry (ICP-MS) to facilitate the speciation of intracellular cadmium species. The incorporation of sodium dodecyl sulfate (SDS) in running buffer significantly reduces the peak width of Cd2+from 170 s to 26 s in the electrophoretogram, causing a 5.3-fold improvement on the sensitivity. Linear ranges of 0.5-50 mg L-1,0.056-5.6 mg L-1 and 0.1-10 mg L-1 are achieved for MTs, Cd-MTs (Cd) and Cd2+, respectively, along with detection limits of 0.013 mg L-1 for Cd-MTs (Cd) and 0.020 mg L-1 for Cd2+. The transformation of cadmium in HepG2 and MCF-7 cells is evaluated after their incubation with Cd2+ reinforced culture medium. Intracellular free Cd2+ cation and Cd-MTs are identified, along with Cd2+ transformation to Cd-glutathione (GSH) adduct/complex, as further demonstrated by ESI-MS.
Collapse
|
5
|
Jiang T, Yu N, Kim J, Murgo JR, Kissai M, Ravichandran K, Miracco EJ, Presnyak V, Hua S. Oligonucleotide Sequence Mapping of Large Therapeutic mRNAs via Parallel Ribonuclease Digestions and LC-MS/MS. Anal Chem 2019; 91:8500-8506. [PMID: 31129964 DOI: 10.1021/acs.analchem.9b01664] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Characterization of mRNA sequences is a critical aspect of mRNA drug development and regulatory filing. Herein, we developed a novel bottom-up oligonucleotide sequence mapping workflow combining multiple endonucleases that cleave mRNA at different frequencies. RNase T1, colicin E5, and mazF were applied in parallel to provide complementary sequence coverage for large mRNAs. Combined use of multiple endonucleases resulted in significantly improved sequence coverage: greater than 70% sequence coverage was achieved on mRNAs near 3000 nucleotides long. Oligonucleotide mapping simulations with large human RNA databases demonstrate that the proposed workflow can positively identify a single correct sequence from hundreds of similarly sized sequences. In addition, the workflow is sensitive and specific enough to detect minor sequence impurities such as single nucleotide polymorphisms (SNPs) with a sensitivity of less than 1%. LC-MS/MS-based oligonucleotide sequence mapping can serve as an orthogonal sequence characterization method to techniques such as Sanger sequencing or next-generation sequencing (NGS), providing high-throughput sequence identification and sensitive impurity detection.
Collapse
Affiliation(s)
- Tao Jiang
- Moderna Inc. , 500 Technology Square , Cambridge , Massachusetts 02139 , United States
| | - Ningxi Yu
- Department of Chemistry , University of Cincinnati , Cincinnati , Ohio 45221 , United States
| | - Jaeah Kim
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy , University of Georgia , Athens , Georgia 30602 , United States
| | - John-Ross Murgo
- Moderna Inc. , 500 Technology Square , Cambridge , Massachusetts 02139 , United States
| | - Mildred Kissai
- Moderna Inc. , 500 Technology Square , Cambridge , Massachusetts 02139 , United States
| | - Kanchana Ravichandran
- Moderna Inc. , 500 Technology Square , Cambridge , Massachusetts 02139 , United States
| | - Edward J Miracco
- Moderna Inc. , 500 Technology Square , Cambridge , Massachusetts 02139 , United States
| | - Vladimir Presnyak
- Moderna Inc. , 500 Technology Square , Cambridge , Massachusetts 02139 , United States
| | - Serenus Hua
- Moderna Inc. , 500 Technology Square , Cambridge , Massachusetts 02139 , United States
| |
Collapse
|
6
|
Xiao X, Zhang Y, Wu J, Jia L. Poly(norepinephrine)-coated open tubular column for the separation of proteins and recombination human erythropoietin by capillary electrochromatography. J Sep Sci 2017; 40:4636-4644. [DOI: 10.1002/jssc.201700720] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/04/2017] [Accepted: 10/01/2017] [Indexed: 01/28/2023]
Affiliation(s)
- Xue Xiao
- Ministry of Education Key Laboratory of Laser Life Science & Institute of Laser Life Science; College of Biophotonics; South China Normal University; Guangzhou China
| | - Yamin Zhang
- Ministry of Education Key Laboratory of Laser Life Science & Institute of Laser Life Science; College of Biophotonics; South China Normal University; Guangzhou China
| | - Jia Wu
- Ministry of Education Key Laboratory of Laser Life Science & Institute of Laser Life Science; College of Biophotonics; South China Normal University; Guangzhou China
| | - Li Jia
- Ministry of Education Key Laboratory of Laser Life Science & Institute of Laser Life Science; College of Biophotonics; South China Normal University; Guangzhou China
| |
Collapse
|
7
|
Khajehsharifi H, Eskandari Z, Sareban N. Using partial least squares and principal component regression in simultaneous spectrophotometric analysis of pyrimidine bases. ARAB J CHEM 2017. [DOI: 10.1016/j.arabjc.2012.07.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
|
8
|
Zhang Y, Wang W, Ma X, Jia L. Polydopamine assisted fabrication of titanium oxide nanoparticles modified column for proteins separation by capillary electrochromatography. Anal Biochem 2016; 512:103-109. [DOI: 10.1016/j.ab.2016.08.015] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 08/12/2016] [Accepted: 08/18/2016] [Indexed: 01/04/2023]
|
9
|
Influence of the ionic strength of acidic background electrolytes on the separation of proteins by capillary electrophoresis. J Chromatogr A 2016; 1432:145-51. [DOI: 10.1016/j.chroma.2015.12.060] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 12/20/2015] [Accepted: 12/21/2015] [Indexed: 12/16/2022]
|
10
|
Carboxyl modified magnetic nanoparticles coated open tubular column for capillary electrochromatographic separation of biomolecules. J Chromatogr A 2015; 1411:92-100. [DOI: 10.1016/j.chroma.2015.07.111] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 07/27/2015] [Accepted: 07/31/2015] [Indexed: 11/17/2022]
|
11
|
Hiruta Y, Nagumo Y, Suzuki Y, Funatsu T, Ishikawa Y, Kanazawa H. The effects of anionic electrolytes and human serum albumin on the LCST of poly( N -isopropylacrylamide)-based temperature-responsive copolymers. Colloids Surf B Biointerfaces 2015; 132:299-304. [DOI: 10.1016/j.colsurfb.2015.05.032] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 04/28/2015] [Accepted: 05/18/2015] [Indexed: 01/01/2023]
|
12
|
Biacchi M, Bhajun R, Saïd N, Beck A, François YN, Leize-Wagner E. Analysis of monoclonal antibody by a novel CE-UV/MALDI-MS interface. Electrophoresis 2014; 35:2986-95. [PMID: 25070377 DOI: 10.1002/elps.201400276] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 07/01/2014] [Accepted: 07/08/2014] [Indexed: 12/16/2022]
Abstract
mAbs are highly complex proteins that present a wide range of microheterogeneity that requires multiple analytical methods for full structure assessment and quality control. As a consequence, the characterization of mAbs on different levels is particularly product- and time-consuming. CE-MS couplings, especially to MALDI, appear really attractive methods for the characterization of biological samples. In this work, we report the last instrumental development and performance of the first totally automated off-line CE-UV/MALDI-MS/MS. This interface is based on the removal of the original UV cell of the CE apparatus, modification of the spotting device geometry, and creation of an integrated delivery matrix system. The performance of the method was evaluated with separation of five intact proteins and a tryptic digest mixture of nine proteins. Intact protein application shows the acquisition of electropherograms with high resolution and high repeatability. In the peptide mapping approach, a total number of 154 unique identified peptides were characterized using MS/MS spectra corresponding to average sequence coverage of 64.1%. Comparison with NanoLC/MALDI-MS/MS showed complementarity at the peptide level with an increase of 42% when using CE/MALDI-MS coupling. Finally, this work represents the first analysis of intact mAb charge variants by CZE using an MS detection. Moreover, using a peptide mapping approach CE-UV/MALDI-MS/MS fragmentation allowed 100% sequence coverage of the light chain and 92% of the heavy chain, and the separation of four major glycosylated peptides and their structural characterization.
Collapse
Affiliation(s)
- Michael Biacchi
- Laboratoire de Spectrométrie de Masse des Interactions et des Systèmes (LSMIS), CNRS-UMR 7140, Université de Strasbourg, Strasbourg, France
| | | | | | | | | | | |
Collapse
|
13
|
Huge BJ, Flaherty RJ, Dada OO, Dovichi NJ. Capillary electrophoresis coupled with automated fraction collection. Talanta 2014; 130:288-93. [PMID: 25159411 DOI: 10.1016/j.talanta.2014.07.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 07/02/2014] [Accepted: 07/07/2014] [Indexed: 10/25/2022]
Abstract
A fraction collector based on a drop-on-demand ink-jet printer was developed to interface capillary zone electrophoresis with a 96 well microtiter plate. We first evaluated the performance of the collector by using capillary zone electrophoresis to analyze a 1mM solution of tetramethylrhodamine; a fluorescent microtiter plate reader was then used to detect the analyte and characterize fraction carryover between wells. Relative standard deviation in peak height was 20% and the relative standard deviation in migration time was 1%. The mean and standard deviation of the tetramethylrhodamine peak width was 5 ± 1 s and likely limited by the 4-s period between droplet deposition. We next injected a complex mixture of DNA fragments and used real-time PCR to quantify the product in a CE-SELEX experiment. The reconstructed electrophoretic peak was 27 s in duration. Finally, we repeated the experiment in the presence of a 30-µM thrombin solution under CE-SELEX conditions; fractions were collected and next-generation sequencing was used to characterize the DNA binders. Over 25,000 sequences were identified with close matches to known thrombin binding aptamers.
Collapse
Affiliation(s)
- Bonnie Jaskowski Huge
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Ryan J Flaherty
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Oluwatosin O Dada
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
| |
Collapse
|
14
|
Zhu G, Sun L, Yan X, Dovichi NJ. Bottom-up proteomics of Escherichia coli using dynamic pH junction preconcentration and capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry. Anal Chem 2014; 86:6331-6. [PMID: 24852005 PMCID: PMC4082393 DOI: 10.1021/ac5004486] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
We report the use of the dynamic
pH junction based capillary zone
electrophoresis-electrospray ionization-tandem mass spectrometry (CZE-ESI-MS/MS)
for bottom-up proteomics with an electrokinetically pumped sheath-flow
nanospray capillary electrophoresis-mass spectrometry (CE-MS) interface
and both LTQ-XL and LTQ-Orbitrap-Velos mass spectrometers. Conventional
injection of 20 nL of a 1 mg/mL BSA digest identified 37 peptides
and produced 66% sequence coverage. In contrast, pH junction injection
of 130 nL (or larger) of a 0.05 mg/mL BSA digest identified 40 peptides
and produced 70% coverage using a pH 6.5 sample buffer and the LTQ.
A 20 nL conventional injection of a 1 mg/mL Escherichia coli digest identified 508 peptides and 199 proteins with the LTQ. A
400 nL pH junction injection of a 0.1 mg/mL E. coli digest identified 527 peptides and 179 proteins with the LTQ. Triplicate
technical replicates of a 0.01 mg/mL sample with 400-nL injection
volume using a pH junction identified 288 ± 9 peptides and 121
± 5 proteins with the LTQ. There was outstanding concordance
in migration time between the pH junction and normal injection. The
pH junction produced narrower peaks and significant concentration
for all but the most acidic components in the sample. Compared with
the conventional stacking method, the pH junction method can generate
comparable performance for small injection volume (20 nL) and significantly
better concentration performance for a large injection volume (200
nL). We also applied the pH junction to three intact standard proteins
and observed a >10× increase in peak intensity compared to
conventional
injection.
Collapse
Affiliation(s)
- Guijie Zhu
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | | | | | | |
Collapse
|
15
|
Zhu G, Sun L, Linkous T, Kernaghan D, McGivney JB, Dovichi NJ. Absolute quantitation of host cell proteins in recombinant human monoclonal antibodies with an automated CZE-ESI-MS/MS system. Electrophoresis 2014; 35:1448-52. [DOI: 10.1002/elps.201300545] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 02/13/2014] [Accepted: 02/14/2014] [Indexed: 01/31/2023]
Affiliation(s)
- Guijie Zhu
- Department of Chemistry and Biochemistry; University of Notre Dame; Notre Dame IN USA
| | - Liangliang Sun
- Department of Chemistry and Biochemistry; University of Notre Dame; Notre Dame IN USA
| | - Travis Linkous
- Department of Analytical Biotechnology; MedImmune; Gaithersburg MD USA
| | - Dawn Kernaghan
- Department of Analytical Biotechnology; MedImmune; Gaithersburg MD USA
| | - James B. McGivney
- Department of Analytical Biotechnology; MedImmune; Gaithersburg MD USA
| | - Norman J. Dovichi
- Department of Chemistry and Biochemistry; University of Notre Dame; Notre Dame IN USA
| |
Collapse
|
16
|
Zhu G, Sun L, Yan X, Dovichi NJ. Stable, reproducible, and automated capillary zone electrophoresis-tandem mass spectrometry system with an electrokinetically pumped sheath-flow nanospray interface. Anal Chim Acta 2014; 810:94-8. [PMID: 24439510 PMCID: PMC3918410 DOI: 10.1016/j.aca.2013.11.057] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 11/24/2013] [Accepted: 11/29/2013] [Indexed: 01/31/2023]
Abstract
A PrinCE autosampler was coupled to a Q-Exactive mass spectrometer by an electrokinetically pumped sheath-flow nanospray interface to perform automated capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry (CZE-ESI-MS/MS). 20ng aliquots of an Escherichia coli digest were injected to evaluate the system. Eight sequential injections over an 8-h period identified 1115±70 (relative standard deviation, RSD=6%) peptides and 270±8 (RSD=3%) proteins per run. The average RSDs of migration time, peak intensity, and peak area were 3%, 24% and 19%, respectively, for 340 peptides with high intensity. This is the first report of an automated CZE-ESI-MS/MS system using the electrokinetically pumped sheath-flow nanospray interface. The results demonstrate that this system is capable of reproducibly identifying over 1000 peptides from an E. coli tryptic digest in a 1-h analysis time.
Collapse
Affiliation(s)
- Guijie Zhu
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Liangliang Sun
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Xiaojing Yan
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Norman J Dovichi
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA.
| |
Collapse
|
17
|
Sun L, Li Y, Champion MM, Zhu G, Wojcik R, Dovichi NJ. Capillary zone electrophoresis-multiple reaction monitoring from 100 pg of RAW 264.7 cell lysate digest. Analyst 2013; 138:3181-8. [PMID: 23591184 DOI: 10.1039/c3an00287j] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Capillary zone electrophoresis-multiple/single reaction monitoring (CZE-MRM/SRM), which employed an electrokinetically driven sheath-flow electrospray interface, was used for the rapid and highly sensitive detection of protein analytes in complex tryptic digests. MRM channels were developed against a commercial exponential mixture of bovine proteins. Five proteins spanning four orders of magnitude concentration range were confidently detected from only 2.5 ng of the digest mixture; the mass detection limits (S/N = 3) of two detected proteins, alpha-casein and glutamate dehydrogenase were about 600 zmol and 30 amol, respectively. This technique was then applied to a RAW 264.7 cell lysate digest. Three proteins were confidently and reproducibly detected from 100 pg of this digest. The sample amount corresponds to the approximate protein content from a single cell, which suggests that CZE-MRM may be a useful analytical tool in chemical cytometry. In addition to providing highly sensitive detection of proteins in complex mixtures, this system is highly rapid; migration time of the protein digests was less than 10 min.
Collapse
Affiliation(s)
- Liangliang Sun
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | | | | | | | | | | |
Collapse
|
18
|
Special Applications. CHROMATOGRAPHY 2013. [DOI: 10.1002/9780471980582.ch15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
19
|
Zhu G, Sun L, Yan X, Dovichi NJ. Single-shot proteomics using capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry with production of more than 1250 Escherichia coli peptide identifications in a 50 min separation. Anal Chem 2013; 85:2569-73. [PMID: 23394296 DOI: 10.1021/ac303750g] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Capillary zone electrophoresis (CZE)-electrospray ionization-tandem mass spectrometry (ESI-MS/MS) was optimized and applied for analysis of 1-100 ng Escherichia coli protein digests in a single run (single-shot analysis). The system employed an electrokinetically pumped nanospray interface, a coated capillary, and stacking conditions for sample injection. More than 1 250 peptides were identified by optimized single-shot CZE-ESI-MS/MS with 100 ng digest loaded and 50 min analysis time. When 10 ng and 1 ng digests were loaded, about 1 000 and 600 peptides were identified in a single-shot analysis, respectively. Compared with single-shot ultraperformance liquid chromatography (UPLC)-ESI-MS/MS, CZE-ESI-MS/MS produced fewer peptide IDs (1 377 ± 128 vs 1 875 ± 32) for large sample loading amounts (100 ng) with the same mass spectrometer time (50 min). However, when the loaded digest was mass limited (1 ng), CZE-ESI-MS/MS generated many more peptide identifications than UPLC-ESI-MS/MS (627 ± 38 vs 342 ± 113). In addition, CZE-ESI-MS/MS and UPLC-ESI -MS/MS provided complementary peptide level identifications. These results suggest that CZE-ESI-MS/MS may be useful for large-scale, comprehensive, and confident proteomics analysis.
Collapse
|
20
|
Electrophoretic heterogeneity limits the utility of streptavidin-β-galactosidase as a probe in free zone capillary electrophoresis separations. Protein J 2013; 32:81-8. [PMID: 23325029 DOI: 10.1007/s10930-013-9464-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Single molecule assays were performed on streptavidin-β-galactosidase using a capillary electrophoresis-based protocol in order to assess the suitability of single molecule β-galactosidase assays for adaptation to the detection of single copies of target DNA. The conjugate was found to have a heterogeneous catalytic rate, showing an average rate of 44,000 ± 24,000 min(-1), which is similar to that of the unmodified enzyme. Electrophoretic mobility was also measured on individual molecules and determined to be -1.32 × 10(-4) ± 0.19 × 10(-4) cm(2)V(-1)s(-1). The variance in mobility was several times that reported for the unmodified enzyme. The electrophoretic heterogeneity was found to result in the formation of a broad window of peaks in the resultant electropherograms of free zone separations of small plugs of streptavidin-β-galactosidase. This range of mobilities largely overlapped with that of the conjugate bound to primer and plasmid containing a target DNA sequence. This overlap suggests that the separation of free conjugate from that bound to target DNA, which is a requirement for application of the single enzyme molecule assay to the detection of target DNA sequences, is not plausible using free zone capillary electrophoresis.
Collapse
|
21
|
Sun L, Zhu G, Li Y, Wojcik R, Yang P, Dovichi NJ. CZE-ESI-MS/MS system for analysis of subnanogram amounts of tryptic digests of a cellular homogenate. Proteomics 2012; 12:3013-9. [PMID: 22888077 DOI: 10.1002/pmic.201200100] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 06/14/2012] [Accepted: 06/18/2012] [Indexed: 12/15/2022]
Abstract
We report the performance of capillary zone electrophoresis coupled with an electrokinetically pumped electrospray interface and an Orbitrap-Velos mass spectrometer for high sensitivity protein analysis. We first investigated the system for quantitation of the tryptic digest of BSA. The system produced outstanding linearity with respect to peak height, number of peptide IDs, and spectral counts across the range of 12 nM to 750 nM (60 amol to 3.5 fmol) of BSA injected. One peptide produced a detection limit of 0.3 nM (1.5 amol) injected. We also analyzed 700 pg of a tryptic digest prepared from a RAW264.7 cell lysate; ten proteins were identified in triplicate analyses after filtering the data with peptide confidence value as high. This sample size corresponds to the protein content of approximately ten eukaryotic cells.
Collapse
Affiliation(s)
- Liangliang Sun
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | | | | | | | | | | |
Collapse
|
22
|
Yoshimura Y, Tanaka H, Dovichi NJ, Hindsgaul O, Palcic MM. Application of Fluorescently-Labeled Glycosphingolipids to Metabolic Profiling in Single Cells Using Capillary Electrophoresis. TRENDS GLYCOSCI GLYC 2012. [DOI: 10.4052/tigg.24.169] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
23
|
Bo T, Liu F, An Li K, Liu H. Comparison of Different Capillary Electrophoresis Modes and HPLC for the Separation of Xanthones. J LIQ CHROMATOGR R T 2011. [DOI: 10.1081/jlc-120018899] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Tao Bo
- a Key Laboratory of Bioorganic Chemistry and Molecular Engineering , Ministry of Education, College of Chemistry and Molecular Engineering, Peking University , Beijing , 100871 , P.R. China
| | - Feng Liu
- a Key Laboratory of Bioorganic Chemistry and Molecular Engineering , Ministry of Education, College of Chemistry and Molecular Engineering, Peking University , Beijing , 100871 , P.R. China
| | - Ke An Li
- a Key Laboratory of Bioorganic Chemistry and Molecular Engineering , Ministry of Education, College of Chemistry and Molecular Engineering, Peking University , Beijing , 100871 , P.R. China
| | - Huwei Liu
- a Key Laboratory of Bioorganic Chemistry and Molecular Engineering , Ministry of Education, College of Chemistry and Molecular Engineering, Peking University , Beijing , 100871 , P.R. China
| |
Collapse
|
24
|
Wang H, Knobel G, Wilson WB, Calimag-Williams K, Campiglia AD. Gold nanoparticles deposited capillaries for in-capillary microextraction capillary zone electrophoresis of monohydroxy-polycyclic aromatic hydrocarbons. Electrophoresis 2011; 32:720-7. [DOI: 10.1002/elps.201000516] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Revised: 01/03/2011] [Accepted: 01/03/2011] [Indexed: 11/10/2022]
|
25
|
Jiang D, Sims CE, Allbritton NL. Microelectrophoresis platform for fast serial analysis of single cells. Electrophoresis 2010; 31:2558-65. [PMID: 20603824 DOI: 10.1002/elps.201000054] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A capillary-based microelectrophoresis platform for fast serial analysis of single cells is described. In this system, the capillary remains fixed and a two-channel flow system is used to rapidly switch the buffer surrounding the capillary inlet from a physiological buffer to an electrophoretic buffer. Single cells are retained in the physiologic buffer channel utilizing an array of cell microwells patterned into the channel floor. The defined addresses of the cells on the array enable the sequential delivery of individual cells to the inlet of the capillary, where a focused laser pulse lyses the cell. The cell chamber is moved along a preordained route so that the inlet of the capillary is located in the electrophoresis buffer for separation and the physiological buffer during cell sampling. The throughput of the current system is limited by peak overlap between successive samples. Key characterizations of this system including the fluid flow rates, the cell array dimensions, and laser energies were performed. To demonstrate this system, 28 cells loaded with Oregon green and fluorescein were serially analyzed in under 16 min, a rate of 1.8 cells/min.
Collapse
Affiliation(s)
- Dechen Jiang
- Department of Chemistry, University of North Carolina, Chapel Hill, NC, USA
| | | | | |
Collapse
|
26
|
Kaushik V, Cook N, Liang AY, Desai UR, Sidorov V. Chemoselective precipitation of lactose from a lactose/sucrose mixture: proof of concept for a new separation methodology. Supramol Chem 2010. [DOI: 10.1080/10610278.2010.500732] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Vivek Kaushik
- a Department of Chemistry , Virginia Commonwealth University , Richmond , VA , 23284 , USA
| | - Nicole Cook
- a Department of Chemistry , Virginia Commonwealth University , Richmond , VA , 23284 , USA
| | - Ayie Y. Liang
- b Institute of Structural Biology and Drug Discovery, Virginia Commonwealth University , Richmond , VA , 23298 , USA
| | - Umesh R. Desai
- b Institute of Structural Biology and Drug Discovery, Virginia Commonwealth University , Richmond , VA , 23298 , USA
| | - Vladimir Sidorov
- a Department of Chemistry , Virginia Commonwealth University , Richmond , VA , 23284 , USA
| |
Collapse
|
27
|
He Y, Lacher NA, Hou W, Wang Q, Isele C, Starkey J, Ruesch M. Analysis of identity, charge variants, and disulfide isomers of monoclonal antibodies with capillary zone electrophoresis in an uncoated capillary column. Anal Chem 2010; 82:3222-30. [PMID: 20345127 DOI: 10.1021/ac9028856] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A set of related capillary zone electrophoresis (CZE) methods have been developed for the analysis of identity, charge variants, and disulfide isoforms of IgG monoclonal antibodies (mAbs). These methods utilize an uncoated capillary column. The combined use of concentrated zwitterionic (e-amino-caproic acid) buffer and acid flushing was effective in minimizing the adsorption of protein to the inner wall of a bare capillary. Under these conditions, a selective and reproducible separation of multiple IgG1 and IgG2 monoclonal antibodies (mAbs) was obtained with a long capillary column (40 cm effective length), allowing the reliable identification of different mAbs by migration time. A rapid ( approximately 10 min) and selective separation of charged variants of IgG mAbs was attained using a short capillary column (10 cm effective length). Finally, the addition of urea in the separation buffer resulted in the separation of disulfide isoforms of IgG2 mAbs by CZE. CZE methods using an uncoated capillary column offer a versatile, generic, and economical approach to the evaluation of identity, charge heterogeneity, and disulfide isoforms of IgG antibodies.
Collapse
Affiliation(s)
- Yan He
- Analytical R&D, Pfizer BioTherapeutics R&D Pharmaceutical Sciences, 700 Chesterfield Parkway West, Chesterfield, Missouri 63017, USA.
| | | | | | | | | | | | | |
Collapse
|
28
|
Ren X, Qu F, Zhang L, Ding J, Liu Q. Continuous intact cell detection and viability determination by CE with dual-wavelength detection. Electrophoresis 2010; 31:324-30. [PMID: 20024918 DOI: 10.1002/elps.200900417] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We introduce here a method for continuous intact cell detection and viability determination of individual trypan blue stained cells by CE with ultraviolet-visible dual-wavelength detection. To avoid cell aggregation or damage during electrophoresis, cells after staining were fixed with 4% formaldehyde and were continuously introduced into the capillary by EOF. The absorbance of a cell at 590 nm was used to determine its viability. An absorbance of two milli-absorbance unit at 590 nm was the clear cut-off point for living and dead Hela cells in our experiments. Good viability correlation between the conventional trypan blue staining assay and our established CE method (correlation coefficient, R(2)=0.9623) was demonstrated by analysis of cell mixtures with varying proportions of living and dead cells. The CE method was also used to analyze the cytotoxicity of methylmercury, and the results were in good agreement with the trypan blue staining assay and 3-(4,5-dimethyl-2-thiazyl)-2,5-diphenyl-2H-tetrazolium bromide methods. Compared with the 3-(4,5-dimethyl-2-thiazyl)-2,5-diphenyl-2H-tetrazolium bromide method, our established CE method can be easily automated to report cell viability based on the state of individual cells. Tedious manual cell counting and human error due to investigator bias can be avoided by using this method.
Collapse
Affiliation(s)
- Xiaomin Ren
- School of Life Science, Beijing Institute of Technology, Beijing, PR China
| | | | | | | | | |
Collapse
|
29
|
Vannatta MW, Whitmore CD, Dovichi NJ. CE-MALDI interface based on inkjet technology. Electrophoresis 2010; 30:4071-4. [PMID: 19960472 DOI: 10.1002/elps.200900414] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
An ink jet printer valve and a nozzle were used to deliver matrix and sample from an electrophoresis capillary onto a MALDI plate. The system was evaluated by the separation of a set of standard peptides. That separation generated up to 40 000 theoretical plates in less than 3 min. Detection limits were 500 amol for an ABI TOF-TOF instrument and 2 fmol for an ABI Q-TOF instrument. Over 70% coverage was obtained for the tryptic digest of alpha-lactalbumin in less than 2.5 min.
Collapse
|
30
|
Lin CY, Tseng WL. Selective enrichment of albumin in biological samples by CE using segmental filling with sodium octyl sulfate in the background electrolyte. Electrophoresis 2009; 30:532-9. [DOI: 10.1002/elps.200800367] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
31
|
Fan XF, Li Q, Wang SL, Xu ZR, Du WB, Fang Q, Fang ZL. High-throughput analysis of DNA fragments using a miniaturized CE system combined with a slotted-vial array sample introduction system. Electrophoresis 2008; 29:4733-8. [DOI: 10.1002/elps.200800287] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
32
|
Lin CY, Liu CH, Chang HC, Tseng WL. Enrichment and separation of acidic and basic proteins using the centrifugal ultrafiltration followed by nanoparticle-filled capillary electrophoresis. Electrophoresis 2008; 29:3024-31. [DOI: 10.1002/elps.200700879] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
33
|
Liu Y, Li W, Ling X, Lai X, Li Y, Zhang Q, Zhao Y. Simultaneous Determination of the Active Ingredients in Abelmoschus manihot (L.) Medicus by CZE. Chromatographia 2008. [DOI: 10.1365/s10337-008-0564-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
34
|
Tempels FWA, Underberg WJM, Somsen GW, de Jong GJ. Design and applications of coupled SPE-CE. Electrophoresis 2008; 29:108-28. [DOI: 10.1002/elps.200700149] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
35
|
Lin CY, Yu CJ, Chen YM, Chang HC, Tseng WL. Simultaneous separation of anionic and cationic proteins by capillary electrophoresis using high concentration of poly(diallyldimethylammonium chloride) as an additive. J Chromatogr A 2007; 1165:219-25. [PMID: 17716677 DOI: 10.1016/j.chroma.2007.07.075] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Revised: 07/24/2007] [Accepted: 07/31/2007] [Indexed: 11/16/2022]
Abstract
The simultaneous separation of anionic and cationic proteins has been achieved by addition of high concentration of poly(diallyldimethylammonium chloride) (PDDAC) in capillary electrophoresis. A capillary was filled with PDDAC so that it would act as ion-pair reagents in the separation of anionic proteins. On the other hand, the PDDAC can also be used as coating additives for the analysis of cationic proteins. Increasing the concentration of PDDAC in the separation buffer had the ability to improve the separation efficiency, change the electrophoretic mobility, and alter the separation selectivity; however, this was not true in the case of analyzing proteins by using the PDDAC larger than 1.6%. By both using a buffer containing 1.6% PDDAC and applying pH-stepwise techniques, 13 proteins with a wide range of pI (4.7-11.1) and molecular masses (6.5-198.0 kDa) could be separated within 30 min in a single run. In addition to this separation, we observed not only more peaks from alpha-chymotrypsinogen A and aprotinin but also the bovine serum albumin (BSA) dimer and trimer. With the 50 nL protein injection sample, the limits of detections at signal-to-noise of 3 for proteins are in the range of 0.07-0.79 microM. Except for BSA, the relative standard derivation values of migration time and peak height for all proteins were <1.3 and <6.9%, respectively. We suggested that this proposed method is a promising approach for clinical diagnosis and proteomics applications.
Collapse
Affiliation(s)
- Chin-Yu Lin
- Department of Chemistry, National Sun Yat-sen University, Taiwan
| | | | | | | | | |
Collapse
|
36
|
pH controlled selective transport of proteins through charged ultrafilter membranes under coupled driving forces: An efficient process for protein separation. J Memb Sci 2007. [DOI: 10.1016/j.memsci.2007.04.043] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
37
|
Tenorio-López FA, Valle-Mondragón L, Martínez-Lazcano JC, Sánchez-Mendoza A, Ríos C, Pastelín-Hernández G, Pérez-Severiano F. CZE Determination of Quinolinic Acid in Rat Brain Tissue and Plasma. Chromatographia 2007. [DOI: 10.1365/s10337-007-0241-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
38
|
Bo T, Li K, Liu H. ANALYSIS OF ACTIVE CONSTITUENTS IN RHIZOMA PICRORHIZAE BY CAPILLARY ZONE ELECTROPHORESIS. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-120014379] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Tao Bo
- a College of Chemistry and Molecular Engineering , Peking University , Beijing, 100871, P. R. China
| | - Ke'an Li
- a College of Chemistry and Molecular Engineering , Peking University , Beijing, 100871, P. R. China
| | - Huwei Liu
- b College of Chemistry and Molecular Engineering , Peking University , Beijing, 100871, P. R. China
| |
Collapse
|
39
|
Liu C, Xu X, Wang Q, Chen J. Mathematical model for DNA separation by capillary electrophoresis in entangled polymer solutions. J Chromatogr A 2007; 1142:222-30. [PMID: 17239893 DOI: 10.1016/j.chroma.2006.12.039] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2006] [Revised: 12/12/2006] [Accepted: 12/12/2006] [Indexed: 11/16/2022]
Abstract
A mathematical model of DNA separation by capillary electrophoresis in entangled polymer solution is presented. The mechanism is modeled as a DNA molecule moving through transient pores formed in polymer solutions and colliding with blobs of polymer molecules encountered during migration. By taking account of the average retardation time (t(c)) of DNA-blob collision and calculating the total collision number (N(c)), a quantitative mathematical equation was reported, leading to predictions for the DNA mobility as a function of the experimental conditions like the size of DNA, the polymer concentration and the electric field strength. For DNA fragments in frequent size range, the initial experimental data agree well with the model. The DNA shape function (f(E)) was suggested and then discussed by the experimental data. The relationship between f(E) and electric field strength E was empirically estimated. Then, the average retardation time t(c) was obtained as about (2 approximately 3)x10(-6)s in linear polyacrylamide (LPA) and hydroxyethylcellulose (HEC) solution.
Collapse
Affiliation(s)
- Chunye Liu
- School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | | | | | | |
Collapse
|
40
|
Guan Y, Wang W, Zu Y, Fu Y, Liu J. Capillary zone electrophoresis method for fingerprint of allantoic fluid in normal and infected SPF embryonated chicken eggs. J Virol Methods 2007; 139:12-6. [PMID: 17055591 DOI: 10.1016/j.jviromet.2006.08.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2005] [Revised: 08/14/2006] [Accepted: 08/29/2006] [Indexed: 10/24/2022]
Abstract
A capillary zone electrophoresis method was developed for fingerprint determination of allantoic fluid in specific pathogen free (SPF) embryonated chicken eggs. The effects of some crucial parameters, such as buffer type, pH, wavelength and running voltage on the separation were studied systematically. The components of the allantoic fluid were well separated using a fused-silica uncoated capillary with an effective length of 50 cm and an internal diameter of 50 microm. One hundred millimolars sodium tetraborate buffer containing 20 mM sodium dihydrogen phosphate with a final pH 9.8 was used as a running buffer. Comparative fingerprints of allantoic fluid in normal and infected with infectious bronchitis virus (IBV) SPF embryonated chicken eggs were also evaluated. The results showed that there were significant differences between composition of normal allantoic fluid and allantoic fluid infected with IBV, which led to different migration behavior. This method was shown to be stable and reproducible with a relative standard deviation of less than 5% for both migration time and peak current.
Collapse
Affiliation(s)
- Yang Guan
- Key Laboratory of Forest Plant Ecology, Northeast Forestry University, Hexing Road 26, 150040 Harbin, China
| | | | | | | | | |
Collapse
|
41
|
Abstract
CE- and microchip-based separations coupled with LIF are powerful tools for the separation, detection and determination of biomolecules. CE with certain configurations has the potential to detect a small number of molecules or even a single molecule, thanks to the high spatial coherence of the laser source which permits the excitation of very small sample volumes with high efficiency. This review article discusses the use of LIF detection for the analysis of peptides and proteins in CE. The most common laser sources, basic instrumentation, derivatization modes and set-ups are briefly presented and special attention is paid to the different fluorogenic agents used for pre-, on- and postcapillary derivatization of the functional groups of these compounds. A table summarizing major applications of these derivatization reactions to the analysis of peptides and proteins in CE-LIF and a bibliography with 184 references are provided which covers papers published to the end of 2005.
Collapse
|
42
|
Hapuarachchi S, Janaway GA, Aspinwall CA. Capillary electrophoresis with a UV light-emitting diode source for chemical monitoring of native and derivatized fluorescent compounds. Electrophoresis 2006; 27:4052-9. [PMID: 16983640 DOI: 10.1002/elps.200600232] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We report the utilization of a high power UV light-emitting diode for fluorescence detection (UV-LED-IF) in CE separations. CE-UV-LED-IF allows analysis of a range of environmentally and biologically important compounds, including PAHs and biogenic amines, including neurotransmitters, amino acids, proteins, and peptides, that have been derivatized with UV-excited fluorogenic labels, e.g., o-phthalic dicarboxaldehyde/beta-mercaptoethanol (OPA/beta-ME). The 365 nm UV-LED was used as a stable, low cost source for detection of UV-excited fluorescent compounds. UV-LED-IF was used with both zonal CE separations and MEKC. Native fluorescence detection of PAHs was accomplished with detection limits ranging from 10 nM to 1.3 microM. Detection limits for OPA/beta-ME-labeled glutamic acid and aspartic acid were 11 and 10 nM, respectively, for off-line labeling, and 47 and 47 nM, respectively, for on-line labeling, comparable to UV-laser-based systems. Analysis of OPA/beta-ME-labeled proteins and peptides was performed with 28 and 47 nM detection limits for BSA and myoglobin, respectively.
Collapse
|
43
|
Schley C, Altmeyer MO, Swart R, Müller R, Huber CG. Proteome Analysis of Myxococcus xanthus by Off-Line Two-Dimensional Chromatographic Separation Using Monolithic Poly-(styrene-divinylbenzene) Columns Combined with Ion-Trap Tandem Mass Spectrometry. J Proteome Res 2006; 5:2760-8. [PMID: 17022647 DOI: 10.1021/pr0602489] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Myxobacteria are potent producers of secondary metabolites exhibiting diverse biological activities and pharmacological potential. The proteome of Myxococcus xanthus DK1622 was characterized by two-dimensional chromatographic separation of tryptic peptides from a lysate followed by tandem mass spectrometric identification. The high degree of orthogonality of the separation system employing polymer-based strong cation-exchange and monolithic reversed-phase stationary phases was clearly demonstrated. Upon automated database searching, 1312 unique peptides were identified, which were associated with 631 unique proteins. High-molecular polyketide synthetases and nonribosomal peptide synthetases, known to be involved in the biosynthesis of various secondary metabolites, were readily detected. Besides the identification of gene products associated with the production of known secondary metabolites, proteins could also be identified for six gene clusters, for which no biosynthetic product has been known so far.
Collapse
Affiliation(s)
- Christian Schley
- Department of Chemistry, Instrumental Analysis and Bioanalysis, Saarland University, 66123 Saarbrücken, Germany
| | | | | | | | | |
Collapse
|
44
|
Xiong X, Ouyang J, Baeyens WRG, Delanghe JR, Shen X, Yang Y. Enhanced separation of purine and pyrimidine bases using carboxylic multiwalled carbon nanotubes as additive in capillary zone electrophoresis. Electrophoresis 2006; 27:3243-53. [PMID: 16858724 DOI: 10.1002/elps.200500870] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This paper describes the enhanced separation of adenine (A), hypoxanthine (HX), 8-azaadenine (8-AA), thymine (T), cytosine (C), uracil (U) and guanine (G) by CZE dispersing carboxylic multiwalled carbon nanotubes (c-MWNTs) into the running buffer. The effect of important factors such as c-MWNT nanoparticle concentration, the acidity and concentration of running buffer, and separation voltage were investigated to acquire the optimum conditions. The seven purine and pyrimidine bases could be well separated within 16 min in a 35 cm effective length fused-silica capillary at a separation voltage of +8.0 kV in a 23 mM tetraborate buffer (pH 9.2) containing 8.0 x 10(-5) g/mL c-MWNTs. Under the optimal conditions, the linear ranges were of 2-250 microg/mL for A (R2 = 0.995), 3-200 microg/mL for U (R2 = 0.990) and G (R2 = 0.992), 3-250 microg/mL for T (R2 = 0.998), 2-200 microg/mL for C (R2 = 0.985) and 4-200 microg/mL for HX (R2 = 0.988) and 8-AA (R2 = 0.990). The detection limits were 0.9 microg/mL for A (S/N = 3), 2.4 microg/mL for U, 2.0 microg/mL for T, 1.5 microg/mL for C, 2.5 microg/mL for G and 3.0 microg/mL for HX and 8-AA. The proposed method was successfully applied for determining five purine and pyrimidine bases in yeast RNA.
Collapse
Affiliation(s)
- Xin Xiong
- Department of Chemistry, Beijing Normal University, Beijing, P R China
| | | | | | | | | | | |
Collapse
|
45
|
|
46
|
|
47
|
Murakami Y, Maeda M. Separation of single-stranded DNAs using DNA conjugates having different migration properties in capillary electrophoresis. J Chromatogr A 2006; 1106:118-23. [PMID: 16443456 DOI: 10.1016/j.chroma.2005.08.073] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2005] [Revised: 08/23/2005] [Accepted: 08/25/2005] [Indexed: 10/25/2022]
Abstract
A probe-regulated simultaneous separation (PRESS) using capillary electrophoresis (CE) was developed for separating single-stranded (ss) DNAs. We synthesized two DNA conjugate probes, -(5'-TGTGTGTGT-3')p-AAm(q)- and -(5'-GCCACCAGC-3')m-AAm(n)-, by copolymerizing 5'-methacryloyl-modified ssDNA with acrylamide (AAm), and characterized them in detail. The two probes showed lower electrophoretic mobilities than 5'-methacryloyl-modified ssDNAs. Furthermore, -(5'-TGTGTGTGT-3')p-AAm(q)- showed slightly faster electrophoretic mobility toward the anode than -(5'-GCCACCAGC-3')m-AAm(n)- due to its higher molar fraction of negatively-charged ssDNA. We successfully separated target ssDNAs having the same chain length by using two ssDNA conjugate probes that showed different electrophoretic mobilities, although the separation of these ssDNAs was difficult in conventional capillary electrophoresis systems.
Collapse
Affiliation(s)
- Y Murakami
- Bioengineering Laboratory, RIKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako-Shi, Saitama 351-0198, Japan
| | | |
Collapse
|
48
|
Jiang TF, Lv ZH, Wang YH, Yue ME. Separation of Plant Hormones from Biofertilizer by Capillary Electrophoresis Using a Capillary Coated Dynamically with Polycationic Polymers. ANAL SCI 2006; 22:811-4. [PMID: 16772676 DOI: 10.2116/analsci.22.811] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A new, simple and rapid capillary electrophoresis (CE) method, using hexadimethrine bromide (HDB) as electroosmotic flow (EOF) modifier, was developed for the identification and quantitative determination of four plant hormones, including gibberellin A3 (GA3), indole-3-acetic acid (IAA), alpha-naphthaleneacetic acid (NAA) and 4-chlorophenoxyacetic acid (4-CA). The optimum separation was achieved with 20 mM borate buffer at pH 10.00 containing 0.005% (w/v) of HDB. The applied voltage was -25 kV and the capillary temperature was kept constant at 25 degrees C. Salicylic acid was used as internal standard for quantification. The calibration dependencies exhibited good linearity within the ratios of the concentrations of standard samples and internal standard and the ratios of the peak areas of samples and internal standard. The correlation coefficients were from 0.9952 to 0.9997. The relative standard deviations of migration times and peak areas were < 1.93 and 6.84%, respectively. The effects of buffer pH, the concentration of HDB and the voltage on the resolution were studied systematically. By this method, the contents of plant hormone in biofertilizer were successfully determined within 7 min, with satisfactory repeatability and recovery.
Collapse
Affiliation(s)
- Ting-Fu Jiang
- Marine Drug and Food Institute, Ocean University of China, Qingdao, P. R. China
| | | | | | | |
Collapse
|
49
|
Liu B, Yue ME, Yang SR, Shi YP. Determination of Phenolic Glucosides in Gentiana piasezkii by Capillary Zone Electrophoresis. Chromatographia 2005. [DOI: 10.1365/s10337-005-0684-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
50
|
Jiang TF, Lv ZH, Wang YH. Separation and determination of anthraquinones inCassia obtusifolia (Leguminosae) by micellar electrokinetic capillary electrophoresis. J Sep Sci 2005; 28:2225-9. [PMID: 16318221 DOI: 10.1002/jssc.200500144] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
An MEKC method was developed for the determination of the five pharmaceutically important anthraquinones: chrysophanol (1), physcion (2), emodin (3), aloe-emodinin (4), and rhein (5) in Cassia obtusifolia (Leguminosae). A buffer solution (pH 9.00) composed of 20 mM sodium borate, 20 mM sodium deoxycholate (DOC), and 15% ACN was found to be the most suitable electrolyte for this separation. Regression equations revealed linear relationships (correlation coefficients: 0.9993, 0.9992, 0.9996, 0.9989, and 0.9991) between the peak area of each compound (1, 2, 3, 4, and 5) and its concentration. The RSDs of migration times and peak areas were <1.23 and 2.72% within 1 day, respectively. The effects of pH value, surfactant (DOC) concentration, and organic modifier on the migration were also studied. By this way, the contents of five anthraquinones in the extracts of the seed of C. obtusifolia (Leguminosae) from different sources were successfully determined within 14 min.
Collapse
Affiliation(s)
- Ting-Fu Jiang
- Key Laboratory of Marine Drugs (Ocean University of China), Ministry of Education, China.
| | | | | |
Collapse
|