Biomedical subjects

Jinglan Wang

Publications and source records attributed to Jinglan Wang.

At least 19 recordsLinked to original sources

PubMed2006

A comparison of electrically induced cardiac arrest with cardiac arrest produced by coronary occlusion.

OBJECTIVE: The present study was undertaken to compare an animal model of electrically induced VF with ischemically induced VF. In a preponderance of models of cardiac arrest and resuscitation in intact animals, ventricular fibrillation (VF) is induced by an alternating current delivered directly to the epicardium or endocardium. Yet, the applicability of such animal models has been challenged for it is not an electrical current alone but rather a current generated in the ischemic myocardium that triggers VF. Accordingly, a potentially more clinically relevant model was investigated in which spontaneous VF followed acute myocardial ischemia. METHODS: Twenty anesthetized pigs were randomized to either electrical fibrillation or myocardial ischemia following transient occlusion of the left anterior descending (LAD) coronary artery. RESULTS: VF was untreated for 7 min in both models after which mechanical ventilation and precordial compression were begun. Defibrillation was attempted after 5 min of CPR in both groups. VF appeared within 5.7+/-2.0 min of LAD occlusion. CONCLUSIONS: A significant increase in the number of post-resuscitation premature ventricular beats and recurrent VF followed ROSC and a significantly greater number of shocks was required for restoration of spontaneous circulation (ROSC) after LAD occlusion. Nevertheless, early post-resuscitation myocardial dysfunction, neurological recovery and 72 h survival were indistinguishable between the two models.

Animals↗

PubMed2006

Microvascular blood flow during cardiopulmonary resuscitation is predictive of outcome.

There is growing evidence that microcirculatory blood flow is the ultimate determinant of the outcome in circulatory shock states. We therefore examined changes in the microcirculation accompanying the most severe form of circulatory failure, namely cardiac arrest and the effects of subsequent cardiopulmonary resuscitation. Ventricular fibrillation was electrically induced in nine pigs and untreated for 5min prior to beginning closed chest cardiac compression and attempting electrical defibrillation. Orthogonal polarization spectral imaging was utilized for visualization of the sublingual microcirculation at baseline, 0.5, 1, 3 and 5min after onset of ventricular fibrillation and at 1 and 5min after start of chest compression. Images were also obtained 1 and 5min after restoration of spontaneous circulation. Microvascular flow was graded from 0 (no flow) to 3 (normal flow). Aortic and right atrial pressures were measured and coronary perfusion pressure was computed continuously. Microcirculatory blood flow decreased to less than one-fourth within 0.5min after inducing ventricular fibrillation. Precordial compression partially restored microvascular flow in each animal. In animals that were successfully resuscitated, microvascular flow was significantly greater after 1 and 5min of chest compression than in animals with failed resuscitation attempts. Microvascular blood flow was highly correlated with coronary perfusion pressure (r=0.82, p<0.01). Microvascular blood flow in the sublingual mucosa is therefore closely related to coronary perfusion pressure during cardiopulmonary resuscitation and both are predictive of outcome.

Animals↗

PubMed2006

Method for quantitative proteomics research by using metal element chelated tags coupled with mass spectrometry.

The mass spectrometry-based methods with a stable isotope as the internal standard in quantitative proteomics have been developed quickly in recent years. But the use of some stable isotope reagents is limited by the relative high price and synthetic difficulties. We have developed a new method for quantitative proteomics research by using metal element chelated tags (MECT) coupled with mass spectrometry. The bicyclic anhydride diethylenetriamine-N,N,N',N' ',N' '-pentaacetic acid (DTPA) is covalently coupled to primary amines of peptides, and the ligand is then chelated to the rare earth metals Y and Tb. The tagged peptides are mixed and analyzed by LC-ESI-MS/MS. Peptides are quantified by measuring the relative signal intensities for the Y and Tb tag pairs in MS, which permits the quantitation of the original proteins generating the corresponding peptides. The protein is then identified by the corresponding peptide sequence from its MS/MS spectrum. The MECT method was evaluated by using standard proteins as model sample. The experimental results showed that metal chelate-tagged peptides chromatographically coeluted successfully during the reversed-phase LC analysis. The relative quantitation results were accurate for proteins using MECT. DTPA modification of the N-terminal of peptides promoted cleaner fragmentation (only y-series ions) in mass spectrometry and improved the confidence level of protein identification. The MECT strategy provides a simple, rapid, and economical alternative to current mass tagging technologies available.

Amino Acid Sequence↗

PubMed2006

A dataset of human fetal liver proteome identified by subcellular fractionation and multiple protein separation and identification technology.

A high throughput process including subcellular fractionation and multiple protein separation and identification technology allowed us to establish the protein expression profile of human fetal liver, which was composed of at least 2,495 distinct proteins and 568 non-isoform groups identified from 64,960 peptides and 24,454 distinct peptides. In addition to the basic protein identification mentioned above, the MS data were used for complementary identification and novel protein mining. By doing the analysis with integrated protein, expressed sequence tag, and genome datasets, 223 proteins and 15 peptides were complementarily identified with high quality MS/MS data.

Cell Membrane↗

PubMed2006

One-shock versus three-shock defibrillation protocol significantly improves outcome in a porcine model of prolonged ventricular fibrillation cardiac arrest.

BACKGROUND: The success of resuscitation with a 1-shock versus the conventional 3-shock defibrillation protocol was investigated subject to the range of treatment variation imposed by automated external defibrillators (AEDs). METHODS AND RESULTS: Ventricular fibrillation was induced in 44 domestic pigs. After 7 minutes of untreated VF, animals were randomized among 4 groups representing all combinations of the 1- versus 3-shock protocol and 2 different AED regimens (AED1, AED2). Because few AEDs support a 1-shock protocol, manual defibrillators were used to replicate the AED treatment regimen: electrical waveform, dose sequence, and cardiopulmonary resuscitation (CPR) interruption intervals. Initial shock(s) were delivered, followed by 60 seconds of CPR, and the treatment was repeated until resuscitation was successful or for 15 minutes. The 1-shock protocol was associated with improved outcome, reducing CPR interruptions from 45% to 34% of total resuscitation time (P=0.019) and increasing survival from 64% to 100% (P=0.004). Survival was 91% for AED1 versus 36% for AED2 (P=0.024) with a 3-shock protocol but was increased to 100% for both by adoption of a 1-shock protocol. Improvements in postresuscitation left ventricular ejection fraction and stroke volume were observed with AED1 compared with AED2 (difference of means, 15% and 28% of baseline respectively, P<0.001) regardless of defibrillation protocol. CONCLUSIONS: Adoption of a 1-shock versus a 3-shock resuscitation protocol improved survival and minimized outcome differences imposed by variations in AED design and implementation. When a conventional 3-shock defibrillation protocol was used, however, the choice of AED had a significant impact on resuscitation outcome.

Animals↗

PubMed2006

The characteristics of postcountershock pulseless electrical activity may indicate the outcome of CPR.

OBJECTIVES: When ventricular fibrillation is cardioverted to pulseless electrical activity (PEA), PEA has been regarded as a non-resuscitatable rhythm. Yet, recent reports and our earlier observations suggested otherwise. We therefore investigated outcomes after postcountershock PEA, and aimed to develop a scoring system for outcome classification at the onset of initial postcountershock PEA. METHODS: Data from 215 domestic pigs were retrospectively reviewed. VF was induced and untreated for 7 min. Defibrillation was attempted with up to three 150 J biphasic shocks. Failing to restore spontaneous circulation (ROSC), 1 min of CPR preceded subsequent sequences of shocks until animals were resuscitated or for a total of 15 min. Fifty-nine instances of PEA followed defibrillation, including 29 animals that attained ROSC. RESULTS: ROSC animals required a shorter interval between the first shock and the initial postcountershock PEA, fewer shocks prior to onset of initial postcountershock PEA, demonstrated a greater VF wavelet amplitude prior to onset of initial PEA, smaller QRS intervals, and higher heart rates. Using Fisher's linear discriminant analysis, 79.3% of the ROSC and 63.3% of non-ROSC cases were predicted correctly. A total of 71.2% of all cases were classified correctly. CONCLUSIONS: Animals in which postcountershock PEA was converted to ROSC required shorter intervals from first shock to initial postcountershock PEA, fewer shocks prior to onset of initial postcountershock PEA, had greater VF wavelet amplitude prior to initial postcountershock PEA, small QRS intervals, and higher heart rates. Fisher's discriminant analysis is helpful in predicting the likelihood of ROSC for an individual animal presenting with postcountershock PEA.

Animals↗

PubMed2006

Phosphopeptide detection using automated online IMAC-capillary LC-ESI-MS/MS.

IMAC has become a commonly used technique in phosphoprotein analysis because of its affinity for phosphopeptides. However, the commonly used strategy combining offline IMAC enrichment with desalting procedures prior to MS/MS makes this method laborious. Here we report the development of a robust and automatic IMAC-capillary RP HPLC-ESI MS/MS technology platform, by which all procedures needed in phosphopeptide analysis including IMAC enrichment, RP HPLC separation and nanospray MS/MS can be done automatically controlled by the MassLynx program. The platform was optimized by analyzing standard phosphopeptide, and was then applied to the identification of phosphorylation sites of recombinant human telomeric repeat binding factor 1 treated with kinase in vitro, and two phosphorylation sites are defined.

Adenosine Triphosphate↗

PubMed2006

Different immunoaffinity fractionation strategies to characterize the human plasma proteome.

Plasma proteins may often serve as indicators of disease and are a rich source for biomarker discovery. However, the intrinsic large dynamic range of plasma proteins makes the analysis very challenging because a large number of low abundance proteins are often masked by a few high abundance proteins. The use of prefractionation methods, such as depletion of higher abundance proteins before protein profiling, can assist in the discovery and detection of less abundant proteins that may ultimately prove to be informative biomarkers. But there are few studies on comprehensive investigation of the proteins both in the fractions depleted and remainder. In the present study, two different immunoaffinity fractionation columns for the top-6 or the top-12 proteins in plasma were investigated and both the proteins in column-bound and flow-through fractions were subsequently analyzed. A two-dimensional peptide separation strategy, utilizing chromatographic separation techniques, combined with tandem mass spectrometry (MS/MS) was employed for proteomic analysis of the four fractions. Using the established HUPO PPP criteria, a total of 2401 unique plasma proteins were identified. The Multiple Affinity Removal System yielded 921 and 725 unique proteins from the flow-through and bound fractions, respectively, whereas the Seppro MIXED 12 column yielded identification of 897 and 730 unique proteins from the flow-through and bound fractions, respectively. When more stringent criteria, based on searching against the reversed database, were implemented, 529 unique proteins were identified from the four fractions with the confidence in peptide identification increased from 73.6% to 99%. To determine whether the presence of nontarget proteins in the immunoaffinity-bound fraction could be attributed to their interaction with high abundance proteins, co-immunoprecipitation analysis with an antibody to human plasma albumin was performed, which resulted in an identification of 40 unique proteins from the coimmunoprecipitate with the more stringent criteria. This study illustrated that combining the column-bound and flow-through fractions from immunoaffinity separation affords more extensive profiling of the protein content of human plasma. The presence of nontarget proteins in the column-bound fractions may be induced by their binding to the higher abundance proteins targeted by the immunoaffinity column.

Amino Acid Sequence↗

PubMed2006

Effects of biphasic waveforms on outcomes of cardiopulmonary resuscitation in a porcine model of prolonged cardiac arrest.

OBJECTIVES: The effects of two clinically available biphasic waveforms on the success of defibrillation and postresuscitation myocardial dysfunction after prolonged ventricular fibrillation were compared with two newly designed dual-path sequential and simultaneous rectilinear biphasic waveforms. Defibrillation via sequential pulses and encircling, overlapping multiple pathway may depolarize a larger myocardial mass and facilitate transthoracic defibrillation. DESIGN: Animal study. SETTING: Experimental laboratory. SUBJECTS: Thirty-two 40 +/- 3 kg pigs. INTERVENTIONS: Ventricular fibrillation was ischemically induced in 32 pigs. After 7 mins of untreated ventricular fibrillation, cardiopulmonary resuscitation was initiated and continued for 5 mins. Animals were then randomized to receive up to three shocks with a) single-path rectilinear biphasic waveform; b) single-path biphasic truncated exponential waveform; c) dual-path rectilinear biphasic sequential defibrillation; or d) dual-path rectilinear biphasic simultaneous defibrillation. MEASUREMENTS AND MAIN RESULTS: Rectilinear biphasic, dual-path sequential defibrillation, and simultaneous defibrillation had significantly fewer shocks (1.1 +/- 0.4, 1.4 +/- 0.5, 1.3 +/- 0.7, respectively) before restoration of spontaneous circulation than biphasic truncated exponential waveform (2.6 +/- 1.4, p < .005) and less postresuscitation myocardial dysfunction (p < .05). Also, dual-path sequential defibrillation had higher postresuscitation ejection fraction than rectilinear biphasic and dual-path simultaneous defibrillation (p < .005). CONCLUSIONS: The energy requirements for terminating ischemically induced ventricular fibrillation were significantly lower and minimized early postresuscitation myocardial dysfunction in the rectilinear biphasic, dual-path sequential defibrillation, and simultaneous defibrillation than the biphasic truncated exponential waveform. Dual-path sequential defibrillation had less postresuscitation myocardial dysfunction than rectilinear biphasic and dual-path simultaneous defibrillation, but at 72 hrs these differences were no longer significant.

Animals↗

PubMed2005

Enrichment and identification of cysteine-containing peptides from tryptic digests of performic oxidized proteins by strong cation exchange LC and MALDI-TOF/TOF MS.

The extreme complexity of sample and uninformative fragmentation of peptides in MS/MS experiments are two of several real challenges faced by proteomics. In this work, a strategy aimed at tackling these two problems is presented. Briefly, proteins were first oxidized by performic acid to cleave the disulfide bonds and simultaneously convert cysteine residue into its sulfonic form. Then the resultant sulfonic peptides were enriched by SCX chromatography, exploiting the negative solution charge of sulfonic group. The sulfonic peptide could be easily detected by MALDI-MS in negative mode and showed both enhanced fragmentation efficiency and a simplified spectrum in MALDI-MS/MS experiment in positive mode. The strength of the strategy was demonstrated by applying it to bovine serum albumin. Potential use of the strategy in proteomics was also discussed.

Amino Acid Sequence↗

PubMed2005

Identification of degradation products formed during performic oxidation of peptides and proteins by high-performance liquid chromatography with matrix-assisted laser desorption/ionization and tandem mass spectrometry.

Oxidation of proteins with performic acid is extensively used to cleave disulfide bonds. Due to its efficiency and many other advantages it deserves more attention especially in proteomics as a method for sample treatment. However, some unwanted degradations can occur during performic oxidation. In this work the degradation products during performic oxidation of two peptides and bovine serum albumin as model substrates were explored by coupling high-performance liquid chromatography (HPLC) to matrix-assisted laser desorption/ionization tandem mass spectrometry (MALDI-TOF/TOFMS). In addition to well-known modifications such as oxidation of tryptophan and oxidation and chlorination of tyrosine, novel degradation products including nonspecific cleavage after asparagine or tryptophan, formylation of lysine, and beta-elimination of cysteine, were observed. Although almost all of these modification/degradation products except oxidation products of tryptophan were formed at sub-stoichiometric levels, they can cause confusion as a result of the sensitivity of mass spectrometry in analysis of the oxidized samples, especially in proteomics research. The results presented here will facilitate the interpretation of analytical data for performate-oxidized samples, and help to select appropriate methods for each unique sample.

Amino Acid Sequence↗

PubMed2005

Levosimendan improves postresuscitation myocardial dysfunction after beta-adrenergic blockade.

In earlier studies, we found that a nonselective beta-adrenergic blocking agent, propranolol, facilitated cardiac resuscitation, reduced postresuscitation myocardial ectopy, and improved postresuscitation survival. However, the potential adverse effects and specifically the negative inotropic actions of propranolol prompted our further investigation of the potential value of a non-beta-adrenergic inotropic drug, levosimendan, in conjunction with propranolol, for minimizing postresuscitation myocardial dysfunction after successful resuscitation from cardiac arrest. Ventricular fibrillation was induced and untreated for 7 minutes in 15 domestic pigs, which were divided into propranolol, propranolol plus levosimendan, and control groups. Propranolol was administered as a bolus dose of 0.1 mg/kg during cardiac arrest. Electrical defibrillation was attempted after 12 minutes of cardiac arrest including 5 minutes of precordial compression. Levosimendan was administered at 10 minutes after successful resuscitation in a dose of 20 microg/kg and followed by infusion of 0.4 microg/kg/min over the ensuing 220 minutes. Propranolol reduced energies or numbers of defibrillatory shocks and postresuscitation myocardial ectopy, and it improved postresuscitation myocardial dysfunction. When levosimendan was added, postresuscitation myocardial contractile function was improved even more.

Adrenergic beta-Antagonists↗

PubMed2005

Comparison between dobutamine and levosimendan for management of postresuscitation myocardial dysfunction.

OBJECTIVE: To investigate the effects of levosimendan, a nonadrenergic inotropic calcium sensitizer, in comparison with adrenergic dobutamine for the management of postresuscitation myocardial dysfunction following resuscitation from prolonged cardiac arrest. DESIGN: Randomized prospective animal study. SETTING: Animal research laboratory. SUBJECTS: Male Yorkshire-cross domestic pigs INTERVENTIONS: Ventricular fibrillation was induced in male domestic pigs weighing between 35 and 40 kg. Cardiopulmonary resuscitation, including precordial compression and mechanical ventilation, was started after 7 mins of untreated cardiac arrest. Electrical defibrillation was attempted after 5 mins of cardiopulmonary resuscitation. Each animal was successfully resuscitated without pharmacologic intervention. Resuscitated animals were randomized to treatment with levosimendan, dobutamine, or saline placebo. The inotropic agents or an equivalent volume of placebo diluents was administered 10 mins after restoration of spontaneous circulation. Levosimendan was administered in a loading dose of 20 microg.kg over 10 mins followed by a 220-min infusion of 0.4 microg.kg.min. Dobutamine was infused into the right atrium in an amount of 5 microg.kg.min. Treatment was continued for a total of 230 mins. MEASUREMENTS AND MAIN RESULTS: Levosimendan and dobutamine produced comparable increases in cardiac output. However, levosimendan produced significantly greater left ventricular ejection fraction and fractional area changes compared with dobutamine and saline placebo. CONCLUSIONS: Levosimendan has the potential of improving postresuscitation myocardial function. It is likely to serve as an alternative to dobutamine as an inotropic agent for management of postresuscitation myocardial dysfunction.

Analysis of Variance↗

PubMed2005

[New advances of high performance separation and analytical techniques for proteins in complex biological systems].

As a new strategy, proteomics is playing more and more important roles in the life sciences after the sequencing of the human genome was completed. Because a biological system is very complex and diverse, the study and application of technological platform for the separation and analysis with high resolution, high sensitivity, high throughput and broad dynamic range have become one of the important and hot spots. The review focused on the new progress of high performance separation and analysis techniques which were applied to the field of proteomics increasingly, such as multidimensional liquid chromatography for pre-fractionation, capillary liquid chromatography coupled with mass spectrometry and capillary electrophoresis interfaced on line with mass spectrometry.

Amino Acid Sequence↗

PubMed2004

Proteomic analysis on structural proteins of Severe Acute Respiratory Syndrome coronavirus.

Recently, a new coronavirus was isolated from the lung tissue of autopsy sample and nasal/throat swabs of the patients with Severe Acute Respiratory Syndrome (SARS) and the causative association with SARS was determined. To reveal further the characteristics of the virus and to provide insight about the molecular mechanism of SARS etiology, a proteomic strategy was utilized to identify the structural proteins of SARS coronavirus (SARS-CoV) isolated from Vero E6 cells infected with the BJ-01 strain of the virus. At first, Western blotting with the convalescent sera from SARS patients demonstrated that there were various structural proteins of SARS-CoV in the cultured supernatant of virus infected-Vero E6 cells and that nucleocaspid (N) protein had a prominent immunogenicity to the convalescent sera from the patients with SARS, while the immune response of spike (S) protein probably binding with membrane (M) glycoprotein was much weaker. Then, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to separate the complex protein constituents, and the strategy of continuous slicing from loading well to the bottom of the gels was utilized to search thoroughly the structural proteins of the virus. The proteins in sliced slots were trypsinized in-gel and identified by mass spectrometry. Three structural proteins named S, N and M proteins of SARS-CoV were uncovered with the sequence coverage of 38.9, 93.1 and 28.1% respectively. Glycosylation modification in S protein was also analyzed and four glycosylation sites were discovered by comparing the mass spectra before and after deglycosylation of the peptides with PNGase F digestion. Matrix-assisted laser desorption/ionization-mass spectrometry determination showed that relative molecular weight of intact N protein is 45 929 Da, which is very close to its theoretically calculated molecular weight 45 935 Da based on the amino acid sequence deduced from the genome with the first amino acid methionine at the N-terminus depleted and second, serine, acetylated, indicating that phosphorylation does not happen at all in the predicted phosphorylation sites within infected cells nor in virus particles. Intriguingly, a series of shorter isoforms of N protein was observed by SDS-PAGE and identified by mass spectrometry characterization. For further confirmation of this phenomenon and its related mechanism, recombinant N protein of SARS-CoV was cleaved in vitro by caspase-3 and -6 respectively. The results demonstrated that these shorter isoforms could be the products from cleavage of caspase-3 rather than that of caspase-6. Further, the relationship between the caspase cleavage and the viral infection to the host cell is discussed.

Amino Acid Sequence↗

PubMed2004

A lazaroid mitigates postresuscitation myocardial dysfunction.

OBJECTIVE: Lazaroids, a series of 21-aminosteroids, reduce free radical mediated injury after ischemia and reperfusion. We hypothesized that the lazaroid U-74389G would minimize postresuscitation myocardial dysfunction and thereby improve neurologically meaningful survival in a rodent model after resuscitation from 8 mins of ventricular fibrillation. DESIGN: Randomized, controlled laboratory study. SETTING: University-affiliated research institute. SUBJECTS: Sprague-Dawley rats. INTERVENTIONS: Ventricular fibrillation was electrically induced in ten anesthetized Sprague-Dawley rats. The lazaroid agent U-74389G in a dose of 1 mg.kg-1 or its vehicle serving as a placebo was injected into the right atrium after 7 mins of untreated ventricular fibrillation. One minute after injection of the compound, precordial compression was begun together with mechanical ventilation and continued for 6 mins before attempted electrical defibrillation. MEASUREMENTS AND MAIN RESULTS: All animals were successfully resuscitated. Postresuscitation cardiac index, left ventricular end-diastolic pressure, the rate of left ventricular pressure increase measured at a left ventricular pressure of 40 mm Hg, and the maximum rate of left ventricular pressure decline were significantly less impaired in lazaroid-treated animals. This contrasted with control animals, which had significantly greater myocardial impairment, greater neurologic deficit, and lesser duration of survival. CONCLUSIONS: The lazaroid compound U-74389G, administered during cardiac arrest, mitigated postresuscitation myocardial dysfunction and improved survival.

Animals↗

PubMed2004

Beta1-adrenergic blockade during cardiopulmonary resuscitation improves survival.

OBJECTIVE: The short-acting beta1-selective adrenergic blocking agent, esmolol, was administrated during cardiopulmonary resuscitation with the hypothesis that initial resuscitation and postresuscitation survival would be improved. DESIGN: Prospective, randomized, controlled study. SETTING: Animal research laboratory. SUBJECTS: Male Sprague-Dawley rats. INTERVENTIONS: Ventricular fibrillation was induced in 18 male Sprague-Dawley rats, which were then left untreated for 6 mins before attempted resuscitation with precordial compression, mechanical ventilation, and electrical defibrillation. Animals were randomized to receive 300 microg/kg esmolol in a volume of 200 microL or an equivalent volume of saline placebo during cardiopulmonary resuscitation. Electrical defibrillation was attempted after 12 mins of ventricular fibrillation. MEASUREMENTS AND MAIN RESULTS: Esmolol-treated animals required a significantly smaller number of electrical shocks before resuscitation. Each of the esmolol-treated but only five of nine placebo-treated animals were successfully resuscitated. Postresuscitation contractile and left ventricular diastolic functions of resuscitated animals were significantly better after esmolol administration and duration of survival was significantly increased. CONCLUSIONS: A short-acting beta1-selective adrenergic blocking agent, when administered during cardiopulmonary resuscitation, significantly improved initial cardiac resuscitation, minimized postresuscitation myocardial dysfunction, and increased the duration of postresuscitation survival.

Adrenergic beta-Antagonists↗

PubMed2004

[Studies on relationship between peak capacity and column length for separation of peptides by high performance liquid chromatography].

In the study of proteomics, the high efficiency separation of peptides is very important for the identification of proteins and their interactions. Therefore, the relationship between peak capacity and column length for the separation of peptides on two reversed-phase columns with different lengths by reversed-phase high performance liquid chromatography was investigated and the effect of gradient times on peak capacity and peak width was examined. The experimental results showed that column length has significant effect on peak capacity. Furthermore, longer gradient times increase not only the peak number, but also the peak width, which is very favorable for the detection of more complicated mixture of peptides when they are separated and identified by capillary liquid chromatography combined with tandem mass spectrometry.

Chromatography, High Pressure Liquid↗