1
|
Rollo D, Kulkarni A, Yu K, Fabris D. Investigating the Merits of Microfluidic Capillary Zone Electrophoresis-Mass Spectrometry (CZE-MS) in the Bottom-Up Characterization of Larger RNAs. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:561-574. [PMID: 38350102 DOI: 10.1021/jasms.3c00411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/15/2024]
Abstract
Established bottom-up approaches for the characterization of nucleic acids (NAs) rely on the strand-cleavage activity of nucleotide-specific endonucleases to generate smaller oligonucleotides amenable to gas-phase sequencing. The complexity of these hydrolytic mixtures calls for the utilization of a front-end separation to facilitate full mass spectrometric (MS) characterization. This report explored the merits of microfluidic capillary zone electrophoresis (CZE) as a possible alternative to common liquid chromatography techniques. An oligonucleotide ladder was initially employed to investigate the roles of fundamental analyte features and experimental parameters in determining the outcome of CZE-MS analyses. The results demonstrated the ability to fully resolve the various rungs into discrete electrophoretic peaks with full-width half-height (FWHH) resolution that was visibly affected by the overall amount of material injected into the system. Analogous results were obtained from a digestion mixture prepared by treating yeast tRNAPhe (75 nt) with RNase T1, which provided several well-resolved peaks in spite of the increasing sample heterogeneity. The regular shapes of such peaks, however, belied the fact that most of them contained sets of comigrating species, as shown by the corresponding MS spectra. Even though it was not possible to segregate each species into an individual electrophoretic peak, the analysis still proved capable of unambiguously identifying a total of 29 hydrolytic products, which were sufficient to cover 96% of the tRNAPhe's sequence. Their masses accurately reflected the presence of modified nucleotides characteristic of this type of substrate. The analysis of a digestion mixture obtained from the 364 nt HIV-1 5'-UTR proved to be more challenging. The electropherogram displayed fewer well-resolved peaks and significantly greater incidence of product comigration. In this case, fractionating the highly heterogeneous mixture into discrete bands helped reduce signal suppression and detection bias. As a result, the corresponding MS data enabled the assignment of 248 products out of the possible 513 predicted from the 5'-UTR sequence, which afforded 100% sequence coverage. This figure represented a significant improvement over the 36 total products identified earlier under suboptimal conditions, which afforded only 57% coverage, or the 83 observed by direct infusion nanospray-MS (72%). These results provided a measure of the excellent potential of the technique to support the bottom-up characterization of progressively larger NA samples, such as putative NA therapeutics and mRNA vaccines.
Collapse
Affiliation(s)
- Daniele Rollo
- University of Connecticut, Storrs, Connecticut 06269, United States
| | | | - Kate Yu
- 908 Devices, Boston, Massachusetts 02210, United States
| | - Daniele Fabris
- University of Connecticut, Storrs, Connecticut 06269, United States
| |
Collapse
|
2
|
Analysis of therapeutic nucleic acids by capillary electrophoresis. J Pharm Biomed Anal 2022; 219:114928. [PMID: 35853263 DOI: 10.1016/j.jpba.2022.114928] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 05/04/2022] [Accepted: 07/02/2022] [Indexed: 12/19/2022]
Abstract
Nucleic acids are getting increased attention to fulfill unmet medical needs. The past five years have seen more than ten FDA approvals of nucleic acid based therapeutics. New analytical challenges have been posed in discovery, characterization, quality control and bioanalysis of therapeutic nucleic acids. Capillary electrophoresis (CE) has proven to be an efficient separation technique and has been widely used for analyzing oligonucleotides and nucleic acids. This review discusses the recent technical advances of CE in nucleic acid analysis such as polymeric matrices, separation conditions and detection methods, and the applications of CE to various therapeutic nucleic acids including antisense oligonucleotide (ASO), small interfering ribonucleic acid (siRNA), messenger RNA (mRNA), gene editing tools such as clustered regularly interspaced short palindromic repeats (CRISPR)-based gene and cell therapy, and other nucleic acid related therapeutics.
Collapse
|
3
|
Liu SL, Wang ZG, Xie HY, Liu AA, Lamb DC, Pang DW. Single-Virus Tracking: From Imaging Methodologies to Virological Applications. Chem Rev 2020; 120:1936-1979. [PMID: 31951121 PMCID: PMC7075663 DOI: 10.1021/acs.chemrev.9b00692] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
![]()
Uncovering
the mechanisms of virus infection and assembly is crucial
for preventing the spread of viruses and treating viral disease. The
technique of single-virus tracking (SVT), also known as single-virus
tracing, allows one to follow individual viruses at different parts
of their life cycle and thereby provides dynamic insights into fundamental
processes of viruses occurring in live cells. SVT is typically based
on fluorescence imaging and reveals insights into previously unreported
infection mechanisms. In this review article, we provide the readers
a broad overview of the SVT technique. We first summarize recent advances
in SVT, from the choice of fluorescent labels and labeling strategies
to imaging implementation and analytical methodologies. We then describe
representative applications in detail to elucidate how SVT serves
as a valuable tool in virological research. Finally, we present our
perspectives regarding the future possibilities and challenges of
SVT.
Collapse
Affiliation(s)
- Shu-Lin Liu
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Research Center for Analytical Sciences, College of Chemistry, and School of Medicine , Nankai University , Tianjin 300071 , P. R. China.,Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry , China University of Geosciences , Wuhan 430074 , P. R. China
| | - Zhi-Gang Wang
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Research Center for Analytical Sciences, College of Chemistry, and School of Medicine , Nankai University , Tianjin 300071 , P. R. China
| | - Hai-Yan Xie
- School of Life Science , Beijing Institute of Technology , Beijing 100081 , P. R. China
| | - An-An Liu
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Research Center for Analytical Sciences, College of Chemistry, and School of Medicine , Nankai University , Tianjin 300071 , P. R. China
| | - Don C Lamb
- Physical Chemistry, Department of Chemistry, Center for Nanoscience (CeNS), and Center for Integrated Protein Science Munich (CIPSM) and Nanosystems Initiative Munich (NIM) , Ludwig-Maximilians-Universität , München , 81377 , Germany
| | - Dai-Wen Pang
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Research Center for Analytical Sciences, College of Chemistry, and School of Medicine , Nankai University , Tianjin 300071 , P. R. China.,College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, The Institute for Advanced Studies, and Wuhan Institute of Biotechnology , Wuhan University , Wuhan 430072 , P. R. China
| |
Collapse
|
4
|
Chen CF, Wharton K. Characterization and failure mode analyses of air plasma oxidized PDMS–PDMS bonding by peel testing. RSC Adv 2017. [DOI: 10.1039/c6ra25947b] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
(a) Specimen geometry for peel test. (b) Specimen setup in Instron without loading (c) and under loading. (Units in mm. Dimensions not to scale.)
Collapse
Affiliation(s)
- C.-f. Chen
- Department of Mechanical Engineering
- University of Alaska Fairbanks
- USA
| | - K. Wharton
- Department of Mechanical Engineering
- University of Alaska Fairbanks
- USA
| |
Collapse
|
5
|
Sydes D, Kler PA, Meyer H, Zipfl P, Lutz D, Huhn C. On-chip intermediate LED-IF-based detection for the control of electromigration in multichannel networks. Anal Bioanal Chem 2016; 408:8713-8725. [DOI: 10.1007/s00216-016-0033-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 10/08/2016] [Accepted: 10/13/2016] [Indexed: 11/30/2022]
|
6
|
Hsieh MK, Shih PY, Wei CF, Vickroy TW, Chou CC. Detection of undeclared animal by-products in commercial canine canned foods: Comparative analyses by ELISA and PCR-RFLP coupled with slab gel electrophoresis or capillary gel electrophoresis. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2016; 96:1659-1665. [PMID: 25996551 DOI: 10.1002/jsfa.7268] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 04/23/2015] [Accepted: 05/18/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND The potential presence of undeclared animal by-products in pet foods is not subject to routine examination. Previously published methods for species-based identification of animal by-products have not been used routinely owing to inconsistent results. The present study evaluated the utility of several approaches for accurate identification of animal by-products in 11 commercial brands of canine canned foods. RESULTS Canine canned foods from several countries were analysed by ELISA, PCR-RFLP coupled with slab-gel electrophoresis (SGE) and capillary gel electrophoresis (CGE) to test for evidence of by-products derived from cattle, chicken, sheep or pig. While CGE-based analysis detected all (24) animal-derived by-products that were reported for the 11 test samples, SGE and ELISA detected only 22/24 (92%) and 14/24 (58%) of labelled by-products, respectively. In addition, undeclared animal by-products were found using all three analytical approaches with CGE detecting more positives (19) than SGE (17) or ELISA (5). CONCLUSION Significant disparities were evident between the labelled contents and the detected content of animal by-products. CGE-based testing for PCR products appears to provide greater sensitivity and accuracy than either SGE or ELISA-based methods. As testing of commercial products becomes more reliable and mainstream, manufacturers will need to develop more thorough and accurate labelling protocols.
Collapse
Affiliation(s)
- Ming-Kun Hsieh
- Graduate Institute of Microbiology and Public Health, National Chung Hsing University, Taichung, 402, Taiwan
| | - Pei-Yin Shih
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung Hsing University, Taichung, 402, Taiwan
| | - Chia-Fong Wei
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung Hsing University, Taichung, 402, Taiwan
| | - Thomas W Vickroy
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Chi-Chung Chou
- Department of Veterinary Medicine, College of Veterinary Medicine, National Chung Hsing University, Taichung, 402, Taiwan
| |
Collapse
|
7
|
Ban E, Song EJ. Recent developments and applications of capillary electrophoresis with laser-induced fluorescence detection in biological samples. J Chromatogr B Analyt Technol Biomed Life Sci 2013; 929:180-6. [DOI: 10.1016/j.jchromb.2013.04.028] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 04/18/2013] [Accepted: 04/20/2013] [Indexed: 12/15/2022]
|
8
|
Shen X, Chen X, Tabor DE, Liu Y, Albarghouthi M, Zhang YF, Galinski MS. Size analysis of residual host cell DNA in cell culture-produced vaccines by capillary gel electrophoresis. Biologicals 2013; 41:201-8. [DOI: 10.1016/j.biologicals.2012.12.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 11/27/2012] [Accepted: 12/04/2012] [Indexed: 12/19/2022] Open
|
9
|
Mikuš P, Veizerová L, Piešťanský J, Maráková K, Havránek E. On-line coupled capillary isotachophoresis-capillary zone electrophoresis in hydrodynamically closed separation system hyphenated with laser induced fluorescence detection. Electrophoresis 2013; 34:1223-31. [DOI: 10.1002/elps.201200556] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 12/05/2012] [Accepted: 12/05/2012] [Indexed: 11/05/2022]
Affiliation(s)
- Peter Mikuš
- Department of Pharmaceutical Analysis and Nuclear Pharmacy; Faculty of Pharmacy, Comenius University; Odbojárov; Bratislava; Slovak Republic
| | - Lucia Veizerová
- Department of Pharmaceutical Analysis and Nuclear Pharmacy; Faculty of Pharmacy, Comenius University; Odbojárov; Bratislava; Slovak Republic
| | - Juraj Piešťanský
- Department of Pharmaceutical Analysis and Nuclear Pharmacy; Faculty of Pharmacy, Comenius University; Odbojárov; Bratislava; Slovak Republic
| | - Katarína Maráková
- Department of Pharmaceutical Analysis and Nuclear Pharmacy; Faculty of Pharmacy, Comenius University; Odbojárov; Bratislava; Slovak Republic
| | - Emil Havránek
- Department of Pharmaceutical Analysis and Nuclear Pharmacy; Faculty of Pharmacy, Comenius University; Odbojárov; Bratislava; Slovak Republic
| |
Collapse
|
10
|
Rapid and easy identification of capsular serotypes of Streptococcus pneumoniae by use of fragment analysis by automated fluorescence-based capillary electrophoresis. J Clin Microbiol 2012; 50:3451-7. [PMID: 22875895 DOI: 10.1128/jcm.01368-12] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The purpose of this study was to develop a high-throughput method for the identification of pneumococcal capsular types. Multiplex PCR combined with fragment analysis and automated fluorescent capillary electrophoresis (FAF-mPCR) was utilized. FAF-mPCR was composed of only 3 PCRs for the specific detection of serotypes 1, 2, 3, 4, 5, 6A/6B, 6C, 7F/7A, 7C/(7B/40), 8, 9V/9A, 9N/9L, 10A, 10F/(10C/33C), 11A/11D/11F, 12F/(12A/44/46), 13, 14, 15A/15F, 15B/15C, 16F, 17F, 18/(18A/18B/18C/18F), 19A, 19F, 20, 21, 22F/22A, 23A, 23B, 23F, 24/(24A/24B/24F), 31, 33F/(33A/37), 34, 35A/(35C/42), 35B, 35F/47F, 38/25F, and 39. In order to evaluate the assay, all invasive pneumococcal isolates (n = 394) characterized at Hospital Sant Joan de Déu, Barcelona, Spain, from July 2010 to July 2011 were included in this study. The Wallace coefficient was used to evaluate the overall agreement between two typing methods (Quellung reaction versus FAF-mPCR). A high concordance with Quellung was found: 97.2% (383/394) of samples. The Wallace coefficient was 0.981 (range, 0.965 to 0.997). Only 11 results were discordant with the Quellung reaction. However, latex reaction and Quellung results of the second reference laboratory agreed with FAF-mPCR for 9 of these 11 strains (82%). Therefore, we considered that only 2 of 394 strains (0.5%) were not properly characterized by the new assay. The automation of the process allowed the typing of 30 isolates in a few hours with a lower cost than that of the Quellung reaction. These results indicate that FAF-mPCR is a good method to determine the capsular serotype of Streptococcus pneumoniae.
Collapse
|
11
|
Manta B, Obal G, Ricciardi A, Pritsch O, Denicola A. Tools to evaluate the conformation of protein products. Biotechnol J 2011; 6:731-41. [DOI: 10.1002/biot.201100107] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Revised: 03/31/2011] [Accepted: 04/04/2011] [Indexed: 11/10/2022]
|
12
|
Zhang S, Jiang C, Jia L. Tetrabutylammonium phosphate-assisted separation of multiplex polymerase chain reaction products in non-gel sieving capillary electrophoresis. Anal Biochem 2011; 408:284-8. [DOI: 10.1016/j.ab.2010.09.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Revised: 09/13/2010] [Accepted: 09/15/2010] [Indexed: 10/19/2022]
|
13
|
Elbashir AA, Aboul-Enein HY. Applications of capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C4D) in pharmaceutical and biological analysis. Biomed Chromatogr 2010; 24:1038-44. [DOI: 10.1002/bmc.1417] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
14
|
Microwave-accelerated derivatization for capillary electrophoresis with laser-induced fluorescence detection: A case study for determination of histidine, 1- and 3-methylhistidine in human urine. Talanta 2010; 82:72-7. [DOI: 10.1016/j.talanta.2010.03.061] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Revised: 03/25/2010] [Accepted: 03/27/2010] [Indexed: 11/19/2022]
|
15
|
Ryvolová M, Preisler J, Foret F, Hauser PC, Krásenský P, Paull B, Macka M. Combined Contactless Conductometric, Photometric, and Fluorimetric Single Point Detector for Capillary Separation Methods. Anal Chem 2009; 82:129-35. [DOI: 10.1021/ac902376v] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Markéta Ryvolová
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Jan Preisler
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - František Foret
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Peter C. Hauser
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Pavel Krásenský
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Brett Paull
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Mirek Macka
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| |
Collapse
|
16
|
Stefanowicz-Hajduk J, Filipowicz N, Kosinski I, Ochocka JR. Capillary electrophoresis with dual laser detection in separation of amplified fragment length polymorphism fragments. J Sep Sci 2009; 32:3539-43. [DOI: 10.1002/jssc.200900297] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
17
|
Wang Z, Wang C, Yin J, Li T, Song M, Lu M, Wang H. Focusing and stabilization of bis-intercalating dye-DNA complexes for high-sensitive CE-LIF DNA analysis. Electrophoresis 2008; 29:4454-62. [DOI: 10.1002/elps.200800230] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
18
|
Lai HH, Quinto-Su PA, Sims CE, Bachman M, Li GP, Venugopalan V, Allbritton NL. Characterization and use of laser-based lysis for cell analysis on-chip. J R Soc Interface 2008; 5 Suppl 2:S113-21. [PMID: 18583277 DOI: 10.1098/rsif.2008.0177.focus] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We demonstrate the use of a pulsed laser microbeam for cell lysis followed by electrophoretic separation of cellular analytes in a microfluidic device. The influence of pulse energy and laser focal point within the microchannel on the threshold for plasma formation was measured. The thickness of the poly(dimethylsiloxane) (PDMS) layer through which the beam travelled was a critical determinant of the threshold energy. An effective optical path length, Leff, for the laser beam can be used to predict the threshold for optical breakdown at different microchannel locations. A key benefit of laser-based cell lysis is the very limited zone (less than 5 microm) of lysis. A second asset is the rapid cell lysis times (approx. microseconds). These features enable two analytes, fluorescein and Oregon Green, from a cell to be electrophoretically separated in the channel in which cell lysis occurred. The resolution and efficiency of the separation of the cellular analytes are similar to those of standards demonstrating the feasibility of using a pulsed laser microbeam in single-cell analysis.
Collapse
Affiliation(s)
- Hsuan-Hong Lai
- Department of Electrical Engineering and Computer Science, University of California, Irvine, CA 92697, USA
| | | | | | | | | | | | | |
Collapse
|
19
|
Guo L, Qiu B, Chi Y, Chen G. Using multiple PCR and CE with chemiluminescence detection for simultaneous qualitative and quantitative analysis of genetically modified organism. Electrophoresis 2008; 29:3801-9. [DOI: 10.1002/elps.200800103] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Longhua Guo
- Ministry of Education Key Laboratory of Analysis and Detection Technology for Food Safety, Fuzhou University, Fuzhou, P. R. China
- Department of Chemistry, Fuzhou University, Fuzhou, P. R. China
| | - Bin Qiu
- Ministry of Education Key Laboratory of Analysis and Detection Technology for Food Safety, Fuzhou University, Fuzhou, P. R. China
- Department of Chemistry, Fuzhou University, Fuzhou, P. R. China
| | - Yuwu Chi
- Ministry of Education Key Laboratory of Analysis and Detection Technology for Food Safety, Fuzhou University, Fuzhou, P. R. China
- Department of Chemistry, Fuzhou University, Fuzhou, P. R. China
| | - Guonan Chen
- Ministry of Education Key Laboratory of Analysis and Detection Technology for Food Safety, Fuzhou University, Fuzhou, P. R. China
- Department of Chemistry, Fuzhou University, Fuzhou, P. R. China
| |
Collapse
|
20
|
Liu K, Wang H, Bai J, Wang L. Home-made capillary array electrophoresis for high-throughput amino acid analysis. Anal Chim Acta 2008; 622:169-74. [DOI: 10.1016/j.aca.2008.05.062] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 05/23/2008] [Accepted: 05/27/2008] [Indexed: 11/25/2022]
|
21
|
Lord HL, Rosenfeld J, Raha S, Hamadeh MJ. Automated derivatization and analysis of malondialdehyde using column switching sample preparation HPLC with fluorescence detection. J Sep Sci 2008; 31:387-401. [PMID: 18196531 DOI: 10.1002/jssc.200700390] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Analyte derivatization is advantageous for the analysis of malondialdehyde (MDA) as a biomarker of oxidative stress in biological samples. Conventionally, however, derivatization is time consuming, error-prone and has limited options for automation. We have addressed these challenges for the solid phase analytical derivatization of MDA from small volume tissue homogenate samples. A manual derivatization method was first developed using Amberlite XAD-2 (12 mg) as the solid phase. Subsequently an automated column switching process was developed that provided simultaneous derivatization and extraction of the MDA-DH hydrazone product on a cartridge packed with XAD-2, followed by quantitative elution of the product to an analytical LC column (Waters NovoPak C18, 3.9 x 150 mm). The LOD was 0.02 microg/mL and recovery was quantitative. The method was linear (r(2) >0.999) with precision < 5% from the LOQ (0.06 microg/mL) to at least 35 microg/mL. The method was successfully applied to the analysis of small volume (30 microL) mouse tissue homogenate samples. Endogenous levels of MDA in the tissues ranged from 20 to 40 nmol/g tissue (ca. 0.1-0.2 microg/mL homogenate). Compared to conventional MDA analyses, the current method has advantages in automation, selectivity, precision and sensitivity for analysis from very small sample volumes.
Collapse
Affiliation(s)
- Heather L Lord
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Canada
| | | | | | | |
Collapse
|
22
|
Zhou L, Zhou X, Luo Z, Wang W, Yan N, Hu Z. In-capillary derivatization and analysis of ephedrine and pseudoephedrine by micellar electrokinetic chromatography with laser-induced fluorescence detection. J Chromatogr A 2008; 1190:383-9. [DOI: 10.1016/j.chroma.2008.03.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2008] [Revised: 02/29/2008] [Accepted: 03/06/2008] [Indexed: 10/22/2022]
|
23
|
Nonaqueous capillary electrophoresis with laser-induced fluorescence detection: A case study of comparison with aqueous media. Anal Chim Acta 2008; 611:212-9. [DOI: 10.1016/j.aca.2008.01.084] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2007] [Revised: 01/25/2008] [Accepted: 01/28/2008] [Indexed: 11/22/2022]
|
24
|
Synthesis and spectroscopic properties of new 5-oxazolone derivatives containing an N-phenyl-aza-15-crown-5 moiety. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.08.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
25
|
Gudnason H, Dufva M, Bang D, Wolff A. Comparison of multiple DNA dyes for real-time PCR: effects of dye concentration and sequence composition on DNA amplification and melting temperature. Nucleic Acids Res 2007; 35:e127. [PMID: 17897966 PMCID: PMC2095797 DOI: 10.1093/nar/gkm671] [Citation(s) in RCA: 196] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The importance of real-time polymerase chain reaction (PCR) has increased steadily in clinical applications over the last decade. Many applications utilize SYBR Green I dye to follow the accumulation of amplicons in real time. SYBR Green I has, however, a number of limitations that include the inhibition of PCR, preferential binding to GC-rich sequences and effects on melting curve analysis. Although a few alternative dyes without some of these limitations have been recently proposed, no large-scale investigation into the properties of intercalating dyes has been performed. In this study, we investigate 15 different intercalating DNA dyes for their inhibitory effects on PCR, effects on DNA melting temperature and possible preferential binding to GC-rich sequences. Our results demonstrated that in contrast to the results of SYBR Green I, two intercalating dyes SYTO-13 and SYTO-82 do not inhibit PCR, show no preferential binding to GC rich sequences and do not influence melting temperature, Tm, even at high concentrations. In addition, SYTO-82 demonstrated a 50-fold lower detection limit in a dilution series assay. In conclusion, the properties of SYTO-82 and SYTO-13 will simplify the development of multiplex assays and increase the sensitivity of real-time PCR.
Collapse
Affiliation(s)
- Haukur Gudnason
- Department of Micro- and Nanotechnology, Technical University of Denmark, bldg. 345, DK-2800 Lyngby and Laboratory of Applied Micro-nanotechnology, Department of Poultry, Fish, and Fur Animals, The National Veterinary Institute, Technical University of Denmark, Hangovej 2, DK-8200 Aarhus N, Denmark
| | - Martin Dufva
- Department of Micro- and Nanotechnology, Technical University of Denmark, bldg. 345, DK-2800 Lyngby and Laboratory of Applied Micro-nanotechnology, Department of Poultry, Fish, and Fur Animals, The National Veterinary Institute, Technical University of Denmark, Hangovej 2, DK-8200 Aarhus N, Denmark
| | - D.D. Bang
- Department of Micro- and Nanotechnology, Technical University of Denmark, bldg. 345, DK-2800 Lyngby and Laboratory of Applied Micro-nanotechnology, Department of Poultry, Fish, and Fur Animals, The National Veterinary Institute, Technical University of Denmark, Hangovej 2, DK-8200 Aarhus N, Denmark
| | - Anders Wolff
- Department of Micro- and Nanotechnology, Technical University of Denmark, bldg. 345, DK-2800 Lyngby and Laboratory of Applied Micro-nanotechnology, Department of Poultry, Fish, and Fur Animals, The National Veterinary Institute, Technical University of Denmark, Hangovej 2, DK-8200 Aarhus N, Denmark
- *To whom correspondence should be addressed. Tel:+45 45256305 +45 45887762
| |
Collapse
|
26
|
Chen H, Wu YH, Song DY, Zhang W, Dong XY, Li PW, Lu CM. On-line pre-concentration and UV determination of DNA fragments by dynamic coating capillary electrophoresis and its application to detection of genetically modified oilseed rape based on PCR. Microchem J 2007. [DOI: 10.1016/j.microc.2006.09.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
27
|
Sniehotta M, Schiffer E, Zürbig P, Novak J, Mischak H. CE – a multifunctional application for clinical diagnosis. Electrophoresis 2007; 28:1407-17. [PMID: 17427258 DOI: 10.1002/elps.200600581] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
CE has been used widely as an analytical tool with high separation power taking advantage of size, charge-to-size ratio, or isoelectric point of various analytes. In combination with detection methods, such as UV absorption, electrochemical detection, fluorescence, or mass spectrometry (MS), it allows the separation and detection of inorganic and organic ions, as well as complex compounds, such as polypeptides, nucleic acids, including PCR amplicons from viruses or bacteria. Recent interest in identification of biomarkers of diseases using body fluids leads to development of CE-MS techniques. These applications allowed identification of new potential biomarkers for clinical diagnosis and monitoring of therapeutic interventions. In this report, we present a technical overview of various CE techniques and discuss their applications in clinical medicine.
Collapse
Affiliation(s)
- Maike Sniehotta
- Mosaiques Diagnostics and Therapeutics AG, Hannover, Germany
| | | | | | | | | |
Collapse
|
28
|
Zhou L, Luo Z, Wang S, Hui Y, Hu Z, Chen X. In-capillary derivatization and laser-induced fluorescence detection for the analysis of organophosphorus pesticides by micellar electrokinetic chromatography. J Chromatogr A 2007; 1149:377-84. [PMID: 17412355 DOI: 10.1016/j.chroma.2007.03.040] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Revised: 02/26/2007] [Accepted: 03/05/2007] [Indexed: 11/26/2022]
Abstract
We developed a rapid and sensitive method using in-capillary derivatization and laser-induced fluorescence (LIF) detection for the fully automated analysis of organophosphorus pesticides (OPPs), including glufosinate, aminomethylphosphonic acid (AMPA) and glyphosate by micellar electrokinetic chromatography (MEKC). The potential of 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) as in-capillary derivatization reagent is described for the first time. The unique feature of this MEKC method is the capillary being used as a small reaction chamber. In in-capillary derivatization, the sample and reagent solutions were injected directly into the capillary by tandem mode, followed by an electrokinetic step to enhance the mixing efficiency of analytes and reagent plugs in accordance with their different electrophoretic mobilities. Standing a specified time for reaction, the derivatives were then immediately separated and determined. Careful optimization of the derivatization and separation conditions allowed the determination of glufosinate, AMPA and glyphosate with detection limits of 2.8, 3.6 and 32.2 ng/mL, respectively. These detection limits were comparable to those of 1.4, 1.9 and 23.8 ng/mL obtained from conventional pre-capillary derivatization. Furthermore, repeatability better than 0.40% for migration time and 3.4% for peak area, as well as shorter migration time, was obtained. The method was successfully applied to the analysis of spiked river water sample with satisfactory results.
Collapse
Affiliation(s)
- Lei Zhou
- Department of Chemistry, Lanzhou University, Lanzhou 730000, China
| | | | | | | | | | | |
Collapse
|
29
|
|
30
|
Chiu TC, Chang HT. Stacking and separation of fluorescent derivatives of amino acids by micellar electrokinetic chromatography in the presence of poly(ethylene oxide). J Chromatogr A 2007; 1146:118-24. [PMID: 17300792 DOI: 10.1016/j.chroma.2007.01.113] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2006] [Revised: 01/20/2007] [Accepted: 01/26/2007] [Indexed: 10/23/2022]
Abstract
A new approach for the analysis of large-volume naphthalene-2,3-dicarboxaldehyde (NDA) derivatives of amino acids by micellar electrokinetic chromatography (MEKC) in conjunction with a purple light-emitting diode-induced fluorescence detection is described. In order to optimize resolution, speed, and stacking efficiency, a discontinuous condition is essential for the analysis of NDA-amino acid derivatives. The optimum conditions use 2.0M TB (pH 10.0) buffer containing 40mM sodium dodecyl sulfate (SDS) to fill the capillary, deionized water to dilute samples, and 200mM TB (pH 9.0) containing 10mM SDS to prepare 0.6% poly(ethylene oxide) (PEO). Once high voltage is applied, PEO solution enters the capillary via electroosmotic flow and SDS micelles interact and thus sweep the NDA-amino acid derivatives having smaller electrophoretic mobilities than that of SDS micelles in the sample zone. When the aggregates between SDS micelles and NDA amino acid derivatives enter PEO zone, they are stacked due to decrease in electric field and increases in viscosity. Under the optimum conditions, the concentration and separation of 0.53-microL 13 NDA-amino acid derivatives that are negatively charged has been demonstrated by using a 60-cm capillary, with the efficiencies 0.3-9.0x10(5) theoretical plates and the LODs at signal-to-noise ratio 3 ranging from 0.30 to 2.76nM. When compared to standard injection (30-cm height for 10s), the approach allows the sensitivity enhancements over the range of 50-800 folds for the derivatives. The new approach has been applied to the analysis of a red wine sample, with great linearity of fluorescent intensity against concentrations (R(2)>0.98) and the RSD (three repetitive runs in one day) values of the migration times for the ten identified amino acids less than 2.8%.
Collapse
Affiliation(s)
- Tai-Chia Chiu
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
| | | |
Collapse
|
31
|
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
|
32
|
Xu X, Li L, Weber SG. Electrochemical and optical detectors for capillary and chip separations. Trends Analyt Chem 2007; 26:68-79. [PMID: 18167508 PMCID: PMC1832263 DOI: 10.1016/j.trac.2006.11.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In separations in capillaries or on chips, the most predominant detectors outside of the field of proteomics are electrochemical (EC) and optical. These detectors operate in the μM to pM range on nL peak volumes with ms time resolution. The driving forces for improvement are different for the two classes of detectors.With EC detectors, there are two limitations that the field is trying to overcome. One is the ever-present surface of the electrode which, while often advantageous for its catalytic or adsorptive properties, is also frequently responsible for changes in sensitivity over time. The other is the decoupling of the electrical systems that operate electrokinetic separations from the system operating the detector.With optical detectors, there are similarly a small number of important limitations. One is the need to bring the portability (size, weight and power requirements) of the detection system into the range of EC detectors. The other is broadening and simplifying the applications of fluorescence detection, as it almost always involves derivatization.Limitations aside, the ability to make detector electrodes and focused laser beams of the order of 1 μm in size, and the rapid time response of both detectors has vaulted capillary and chip separations to the forefront of small sample, fast, low mass-detection limit analysis.
Collapse
Affiliation(s)
- Xiaomi Xu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA USA
| | - Ling Li
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA USA
| | - Stephen G. Weber
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA USA
| |
Collapse
|
33
|
Li P, Li SP, Wang YT. Optimization of CZE for analysis of phytochemical bioactive compounds. Electrophoresis 2006; 27:4808-19. [PMID: 17136720 DOI: 10.1002/elps.200600219] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Advantages of CZE such as high efficiency, low cost, short analysis time, and easy implementation result in its wide applications for analysis of phytochemical bioactive compounds (e.g. flavonoids, alkaloids, terpenoids, phenolic acid, saponins, anthraquinones and coumarins). However, several aspects, including sample preparation, separation, and detection have significant effects on CZE analysis. Therefore, optimization of these procedures is necessary for development of the method. In this review, sample preparation such as extraction method and preconcentration, separation factors including buffer type, concentration and pH, additives, voltage and temperature, as well as detection, e.g. direct and indirect UV detection, LIF and MS were discussed for optimization of CZE analysis on phytochemical bioactive compounds. The optimized strategies were also reviewed.
Collapse
Affiliation(s)
- Peng Li
- Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau, China
| | | | | |
Collapse
|
34
|
Casado-Terrones S, Cortacero-Ramírez S, Carrasco-Pancorbo A, Segura-Carretero A, Fernández-Gutiérrez A. Comparative study between a commercial and a homemade capillary electrophoresis instrument for the simultaneous determination of aminated compounds by induced fluorescence detection. Anal Bioanal Chem 2006; 386:1835-47. [PMID: 16964474 DOI: 10.1007/s00216-006-0731-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2006] [Revised: 07/25/2006] [Accepted: 08/03/2006] [Indexed: 10/24/2022]
Abstract
The performance of two capillary electrophoresis (CE) instruments, one commercial and one homemade device, were compared for the determination of derivatised aminated compounds with fluorescein isothiocyanate (FITC). The commercial CE system first uses an argon ion laser as excitation source; the homemade CE device uses an inexpensive blue-light-emitting diode (LED) as the light source and a charge-coupled device (CCD) as the detection system. After fine optimisation of several separation parameters in both devices, a co-electroosmotic flow CE methodology was achieved in coated capillary tubing with 0.001% hexadimetrine bromide (HDB), and 50 mmol L-1 sodium borate at pH 9.3 with 20% 2-propanol for the determination of several amines and aminoacids. Analytical performances, applicability in beer samples and other aspects such as cost or potential for miniaturization have been compared for both devices.
Collapse
Affiliation(s)
- Silvia Casado-Terrones
- Department of Analytical Chemistry, Faculty of Sciences, University of Granada, Avda. Fuentenueva s/n, 18071, Granada, Spain
| | | | | | | | | |
Collapse
|
35
|
Huang YF, Huang CC, Hu CC, Chang HT. Capillary electrophoresis-based separation techniques for the analysis of proteins. Electrophoresis 2006; 27:3503-22. [PMID: 16927348 DOI: 10.1002/elps.200600100] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
CE offers the advantages of high speed, great efficiency, as well as the requirement of minimum amounts of sample and buffer for the analysis of proteins. In this review, we summarize the CE-based techniques coupled with absorption, LIF, and MS detection systems for the analysis of proteins mostly within the past 5 years. The basic principle of each technique and its advantages and disadvantages for protein analysis are discussed in brief. Advanced CE techniques, including on-column concentration techniques and high-efficiency multidimensional separation techniques, for high-throughput protein profiling of complex biological samples and/or of single cells are emphasized. Although the developed techniques provide improved peak capacity, they have not become practical tools for proteomics, mainly because of poor reproducibility, low-sample lading capacity, and low throughput due to ineffective interfaces between two separation dimensions and that between separation and MS systems. In order to identify the complexities and dynamics of the proteomes expressed by cells, tissues, or organisms, techniques providing improved analytical sensitivity, throughput, and dynamic ranges are still demanded.
Collapse
Affiliation(s)
- Yu-Fen Huang
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
| | | | | | | |
Collapse
|
36
|
Lara FJ, García-Campaña AM, Gámiz-Gracia L, Bosque-Sendra JM, Alés-Barrero F. Determination of phenothiazines in pharmaceutical formulations and human urine using capillary electrophoresis with chemiluminescence detection. Electrophoresis 2006; 27:2348-59. [PMID: 16718647 DOI: 10.1002/elps.200500863] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A CE instrument coupled with chemiluminescence (CL) detection was designed for the determination of promethazine hydrochloride (PTH) and promazine hydrochloride (PMH) in real samples. An important enhancement of the CL emission of luminol with potassium ferricyanide was observed in the presence of these phenothiazines; so this system was selected for their detection after CE separation. Parameters affecting the electrophoretic separation were optimized in a univariate way, while those affecting CL detection were optimized by means of a multivariate approach based on the use of experimental designs. Chemometrics was also employed for the study of the robustness of the factors influencing the postcolumn CL detection. The method allows the separation of the phenothiazines in less than 4 min, achieving LODs of 80 ng/mL for PMH and 334 ng/mL for PTH, using sample injection by gravity. Electrokinetic injection was used to obtain lower LODs for the determination of the compounds in biological samples. The applicability of the CE-CL method was illustrated in the determination of PTH in pharmaceutical formulations and in the analysis of PMH in human urine, using a previous SPE procedure, achieving an LOD of 1 ng/mL and recoveries higher than 85%.
Collapse
Affiliation(s)
- Francisco J Lara
- Department of Analytical Chemistry, Faculty of Sciences, University of Granada, Granada, Spain
| | | | | | | | | |
Collapse
|
37
|
Chang PL, Chiu TC, Chang HT. Stacking, derivatization, and separation by capillary electrophoresis of amino acids from cerebrospinal fluids. Electrophoresis 2006; 27:1922-31. [PMID: 16703625 DOI: 10.1002/elps.200500496] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This paper describes the in-column derivatization, stacking, and separation of amino acids by CE in conjunction with light-emitting diode-induced fluorescence using naphthalene-2,3-dicarboxaldehyde (NDA). According to the relative electrophoretic mobilities and the migration direction in tetraborate solution (pH 9.3), the injection order is cyanide, then amino acids, then NDA. Once poly(ethylene oxide) (PEO) migrates through the capillary under EOF, the amino acid.NDA derivatives, amino acids, and CN- ions migrating against the EOF enter the PEO zone. As a result of increases in viscosity and possible interactions with PEO molecules, the reagents/analytes slow down such that they become stacked at the boundary. In comparison with the off-column approach to the analysis of amino acids, our proposed method provides a lower degree of interference from polymeric NDA compounds and other side products. As a result, the plot of the peak height as a function of gamma-aminobutyric acid (GABA) concentration is linear over the range from 10(-5) to 10(-8) M, with the LOD being 4 nM. We demonstrate the diagnostic potential of this approach for the determination of amino acids, including GABA and glutamine, in biological samples through the analysis of large volumes of cerebral spinal fluids without the need for sample pretreatment.
Collapse
Affiliation(s)
- Po-Ling Chang
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
| | | | | |
Collapse
|
38
|
Abstract
This review article with 304 references describes recent developments in CE of proteins, and covers the two years since the previous review (Hutterer, K., Dolník, V., Electrophoresis 2003, 24, 3998-4012) through Spring 2005. It covers topics related to CE of proteins, including modeling of the electrophoretic migration of proteins, sample pretreatment, wall coatings, improving separation, various forms of detection, special electrophoretic techniques such as affinity CE, CIEF, and applications of CE to the analysis of proteins in real-world samples including human body fluids, food and agricultural samples, protein pharmaceuticals, and recombinant protein preparations.
Collapse
|
39
|
Sieben VJ, Backhouse CJ. Rapid on-chip postcolumn labeling and high-resolution separations of DNA. Electrophoresis 2005; 26:4729-42. [PMID: 16283693 DOI: 10.1002/elps.200500459] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
When performing genetic analysis on microfluidic systems, labeling the sample DNA for detection is a critical preparation step. Labeling procedures often involve fluorescently tagged primers and PCRs, which lengthen experimental run times and introduce higher levels of complexity, increasing the overall cost per analysis. Alternatively, on-chip labeling techniques based on intercalating dyes permit rapid labeling of DNA fragments. However, as noted in the literature, the stochastic nature of dye-DNA complex formation hinders the native electrophoretic migration of DNA fragments, degrading the separation resolution. In this study, we present a novel method of controllably labeling DNA fragments at the end of the electrophoretic separation channel in a glass microfluidic chip. Permitting the DNA to separate and labeling just before detection, achieves the rapid labeling associated with intercalators while maintaining the high resolution of native DNA separations. Our analyses are completed in minutes, rather than the hours typical of sample prelabeling. We demonstrate an electrophoretic microchip-based intercalator labeling technique that achieves higher resolution performance than reported in the literature to date.
Collapse
Affiliation(s)
- Vincent J Sieben
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta, Canada
| | | |
Collapse
|
40
|
Minjie X, Wei W, Zhou Z, Yongfei Y. Capillary electrophoresis analysis of hydrogen peroxide induced apoptosis in PC12 cells. J Pharm Biomed Anal 2005; 39:853-60. [PMID: 16039084 DOI: 10.1016/j.jpba.2005.06.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2005] [Revised: 05/13/2005] [Accepted: 06/02/2005] [Indexed: 12/27/2022]
Abstract
Apoptosis is a highly regulated and controlled process of cell death that plays a fundamental role in many biological processes. Abnormal apoptosis of cells is closely related to some diseases such as cancer. Development of a simple and effective method to detect apoptosis is of great importance. In the present paper, capillary electrophoresis (CE) method was applied to distinguish cell apoptosis and necrosis of rat pheochromocytoma (PC12) cells treated by hydrogen peroxide by characterizing the DNA fragmentation. Firstly, effects of separation conditions (voltage, polymer concentration, temperature and injection time) on DNA separation were studied using 100 bp DNA ladders as the analyte. Under optimal separation condition (polyacrylamide coated capillaries: 57.5 cm x 75 microm i.d., effective length: 50 cm; running buffer: 1x TBE containing 2% PVP and 1.2% HEC; separation voltage: 5 kV; temperature: 25 degrees C; electrokinetic injection: 10 kV x 10 s), CE was used to monitor the progress of hydrogen peroxide induced apoptosis of PC12 cells by analyze DNA fragmentation. It was found that normal, apoptotic and neurotic cells had distinct DNA fragmentation patterns analyzed by CE. The results by CE were tested by other current methods (DAPI nuclei staining, flow cytometry analysis and TUNEL) to detect apoptosis and correlated well with those methods. Results show that CE can distinguish cell apoptosis and necrosis, quantify the degree of apoptosis in cells and have advantages of high efficiency, fast sample analysis speed, minute sample consumption and reliable results, which provides an accessorial method in the research of multiple diseases with abnormal apoptosis such as cancer and neurodegenerative diseases.
Collapse
Affiliation(s)
- Xie Minjie
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, PR China.
| | | | | | | |
Collapse
|
41
|
Frade VH, Gonçalves MST, Moura JC. Synthesis and fluorescence properties of side-chain carboxylated 5,9-diaminobenzo[a]phenoxazinium salts. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2005.05.105] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
42
|
Lu MJ, Chiu TC, Chang PL, Ho HT, Chang HT. Determination of glycine, glutamine, glutamate, and γ-aminobutyric acid in cerebrospinal fluids by capillary electrophoresis with light-emitting diode-induced fluorescence detection. Anal Chim Acta 2005. [DOI: 10.1016/j.aca.2005.02.041] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
43
|
Chirino AJ, Mire-Sluis A. Characterizing biological products and assessing comparability following manufacturing changes. Nat Biotechnol 2005; 22:1383-91. [PMID: 15529163 DOI: 10.1038/nbt1030] [Citation(s) in RCA: 237] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Changes in production methods of a biological product may necessitate an assessment of comparability to ensure that these manufacturing changes have not affected the safety, identity, purity, or efficacy of the product. Depending on the nature of the protein or the change, this assessment consists of a hierarchy of sequential tests in analytical testing, preclinical animal studies and clinical studies. Differences in analytical test results between pre- and post-change products may require functional testing to establish the biological or clinical significance of the observed difference. An underlying principle of comparability is that under certain conditions, protein products may be considered comparable on the basis of analytical testing results alone. However, the ability to compare biological materials is solely dependent on the tests used, since no single analytical method is able to compare every aspect of protein structure or function. The advantages and disadvantages of any given method depends on the protein property being characterized.
Collapse
Affiliation(s)
- Arthur J Chirino
- Xencor Inc., 111 West Lemon Avenue, Monrovia, Calfornia 91016, USA.
| | | |
Collapse
|
44
|
Fluorescence detection in capillary electrophoresis. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/s0166-526x(05)45006-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|