环果糖色谱柱分离4组结构类似物

考察了聚苯乙烯键合天然环果糖色谱柱MCI Gel CRS100、硅胶键合天然环果糖色谱柱Frulic N、硅胶键合异丙基氨基甲酸酯衍生环果糖色谱柱Larihc P、硅胶键合R-萘乙基氨基甲酸酯衍生环果糖色谱柱Larihc RN在正相模式下对免疫抑制剂、维生素E、姜黄类化合物、辣椒碱4组结构类似物的分离能力。考察了固定相支撑物、固定相功能基团、流动相组成等条件对色谱分离效率的影响。结果显示MCI Gel CRS100由于其固定相较强的疏水性适用于正相色谱而不适用于亲水作用色谱。衍生化的环果糖色谱柱Larihc P和Larihc RN比天然环果糖色谱柱Frulic N具有更高的选择性。三氟乙酸的加入对环果糖色谱柱在正相色谱中分离能力的影响较小。     

Enantioselective determination of arotinolol in human plasma by HPLC using teicoplanin chiral stationary phase

A sensitive enantioselective high-performance liquid chromatography (HPLC) method was developed and validated to determine S-(+)- and R-(-)-arotinolol in human plasma. Baseline resolution was achieved by using teicoplanin macrocyclic antibiotic chiral stationary phase (CSP) known as Chirobiotic T with a polar organic mobile phase consisting of methanol:glacial acetic acid:triethylamine, 100:0.1:0.1, (v/v/v) at a fl ow rate of 0.8 mL/min and UV detection set at 317 nm. Human plasma was spiked with stock solution of arotinolol enantiomers and labetalol as the internal standard. The assay involved the use of liquid-liquid extraction procedure with ethyl ether under alkaline condition for human plasma sample prior to HPLC analysis. Recoveries for S-(+)- and R-(-)-arotinolol enantiomers were in the range 93-103% at 200-1400 ng/mL level. Intra-day and inter-day precision calculated as %RSD was in the ranges 1.3-3.4 and 1.9-4.5% for both enantiomers, respectively. Intra-day and inter-day accuracies calculated as percentage error were in the ranges 1.2-3.5 and 1.5-6.2% for both enantiomers, respectively. Linear calibration curves in the concentration range 100-1500 ng/mL for each enantiomer showed a correlation coefficient (r) of 0.9998. The limit of quantitation (LOQ) and limit of detection (LOD) for each enantiomer in human plasma were 100 and 50 ng/mL (S/N = 3), respectively.     

Enantiomeric separation of new phytoalexin analogs with cyclofructan chiral stationary phases in normal‐phase mode

For the first time, three different derivatized cyclofructan chiral stationary phases were used for the direct high‐performance liquid chromatographic enantiomeric separation of 11 new racemic analogs of a natural indole phytoalexin. This class of compounds is known to have significant antiproliferative activity and other potentially useful pharmacological properties. The effect of various experimental factors was investigated to optimize the separations in the normal‐phase mode. It was found that the nature of polar modifier and additive in the mobile phase have significant impact on the enantioseparations. Better chiral recognition of analyzed compounds was achieved on (R)‐naphthylethyl carbamate cyclofructan 6 than on isopropyl carbamate cyclofructan 6 and dimethylphenyl carbamate cyclofructan 7. The thermodynamic parameters showed that the chiral separation was enthalpy controlled in all cases.     

Characterization of cyclofructan-based chiral stationary phases by linear free energy relationship

Cyclofructans (CFs), a new class of chiral selectors, have been recently introduced for application in liquid chromatography and capillary electrophoresis. So far, derivatized CFs have performed interesting separation possibilities for a variety of compounds. The current work is focused on characterization of three different CF-based chiral stationary phases (CF-based CSPs), i.e. isopropyl carbamate cyclofructan 6 (IP-CF6), R-naphthylethyl carbamate cyclofructan 6 (RN-CF6) and dimethylphenyl carbamate cyclofructan 7 (DMP-CF7). The linear free energy relationship (LFER) model was used to reveal the dominant interactions participating in the complex retention mechanism. A set of 44 different test solutes, with known solvation parameters, was used to determine the regression coefficients of the LFER equation under two mobile-phase compositions in normal separation mode. The LFER results showed that hydrogen bond acidity, hydrophobicity and dipolarity/polarizibility mostly affect the retention and separation process on the CF-based columns in the studied separation systems.     

Activated carbamate reagent as chiral derivatizing agent for liquid chromatographic optical resolution of enantiomeric amino compounds

Summary A chiral derivatization reagent having activated succinimido carbamate moieties were developed for the optical resolution of enantiomeric amines by high-performance liquid chromatography. Succinimido R-(+)- or S-(–)-1-phenylethyl and R-(+)- or S-(–)-1-(-naphthyl)-ethyl carbamates were synthesized by the reaction of optically active phenylethyl and naphthylethyl amines with discuccinimido carbonate (DSC). These reagents reacted with both primary and secondary amine enantiomers such as amino acids and -amino alcohols to give the corresponding diastereomeric urea derivatives. These diastereomers were efficiently separated by reversed-phase liquid chromatography and detected by their absorption or the fluorescence of the chromophores. The chiral derivatization procedure was applied to the separation and determination of enantiomeric propranolol in serum.     

Enantioanalysis of bisoprolol in human plasma with a macrocyclic antibiotic HPLC chiral column using fluorescence detection and solid phase extraction

A sensitive, enantioselective, high-performance liquid chromatographic (HPLC) method was developed and validated to determine S-(-)- and R-(+)-bisoprolol in human plasma. Baseline resolution was achieved using the teicoplanin macrocyclic antibiotic chiral stationary phase (CSP) known as Chirobiotic T with a polar ionic mobile phase (PIM) consisting of methanol-glacial acetic acid-triethylamine (100 : 0.02 : 0.025, v/v/v) at a flow rate of 1.5 ml/min and fluorescence detection set at 275 nm for excitation and 305 nm for emission. All analyses with S-(-)-atenolol as the internal standard were conducted at ambient temperature. The assay involved the use of a solid-phase extraction procedure for human plasma samples prior to HPLC analysis. The C18 cartridge gave good recovery rates for both enantiomers without any interference. The method was validated over the range of 20-200 ng/ml for each enantiomer concentration. Recovery rates for S-(-)- and R-(+)-bisoprolol enantiomers were in the range of 95-102%. The method proved to be precise (within-run precision expressed as % RSD ranged from 1.0-6.2% and between-run precision ranged from 0.9-6.7%) and accurate (within-run accuracies expressed as percentage error ranged from 0.2-4.8% and between-run accuracies ranged from 0.3-1.7%). The limit of quantitation and limit of detection for each enantiomer in human plasma were 20 and 5 ng/ml, respectively.     

Characterization of the stereoselective metabolism of thiopental and its metabolite pentobarbital via analysis of their enantiomers in human plasma by capillary electrophoresis.

Using capillary zone electrophoresis (CZE) with a 75 mM phosphate buffer at pH 8.5 containing 5 mM hydroxypropyl-gamma-cyclodextrin (OHP-gamma-CD) as chiral selector, the separation of the enantiomers of thiopental and its oxybarbiturate metabolite, pentobarbital, is reported. Enantiomer assignment was performed via preparation of enantiomerically enriched fractions using chiral recycling isotachophoresis (rITP) processing of racemic barbiturates and analysis of rITP fractions by chiral CZE and circular dichroism spectroscopy. Thiopental and pentobarbital enantiomers in plasma were extracted at low pH using dichloromethane and extracts were reconstituted in acetonitrile or 10-fold diluted, achiral running buffer. The stereoselectivity of the thiopental and pentobarbital metabolism was assessed via analysis of 12 plasma samples that stemmed from patients undergoing prolonged or having completed long-term racemic thiopental infusion. The data obtained revealed a modest stereoselectivity with R-(+)-thiopental/S-(-)-thiopental and R-(+)-pentobarbital/S-(-)-pentobarbital plasma ratios being < 1 (P < 0.05 compared to data obtained with racemic controls) and > 1 (P < 0.001), respectively. The total S-(-)-thiopental plasma concentration was found to be on average about 24% higher compared to the concentration of R-(+)-thiopental, whereas the total R-(+)-pentobarbital plasma level was observed to be on average 29% higher compared to the S-(-)-pentobarbital concentration.     

A validated enantioselective HPLC assay of dexibuprofen in dexibuprofen tablet formulations

A high-performance liquid chromatography-diode array detector (HPLC-DAD) method was developed and validated for the quantitation of dexibuprofen in dexibuprofen tablets using ovomucoid chiral stationary phase (Ultron ES-OVM). The mobile phasewas composed of 0.025 M potassium phosphate dibasic (pH 4.5)-methanol-ethanol (85:10:5 v/v/v). The method was validated for specificity, linearity, range, accuracy, precision and robustness. The method was enantiomerspecific for the determination of dexibuprofen [S-(+)-isomer ibuprofen] in the presence of R-(-)-isomer ibuprofen in bulk drug, pharmaceutical dosage form and under stress degradation. The method was linear over the range 15-35 mg/mL with r2 = 0.9995; accuracy and precision were acceptable with %RSD < 2.0%. The method was found to be specific, precise, accurate, robust and stability-indicating, and can be successfully applied for the routine analysis of dexibuprofen in bulk drug and pharmaceutical dosage form.     

Determination of the enantiomeric impurity in S-(-)pantoprazole using high performance liquid chromatography with sulfobutylether-beta-cyclodextrin as chiral additive

A new and accurate HPLC method using sulfobutylether-beta-cyclodextrin (SBE-beta-CD) as chiral mobile phase additive (CMPA) was developed and validated for the determination of R-(+)pantoprazole in S-(-)pantoprazole. The influences of type and concentration of CD, ACN content and buffer pH of mobile phase on the resolution and retention of enantiomers were investigated. A baseline resolution of pantoprazole enantiomers was achieved on a Spherigel C18 column (150 mm x 4.6 mm, 5 microm) using ACN and 10 mM phosphate buffer (pH 2.5) containing 10 mM SBE-beta-CD (15:85 v/v) as mobile phase with a flow rate of 0.9 mL/min at 20 degrees C. The detection wavelength was set at 290 nm. The method was extensively validated in terms of accuracy, precision and linearity according to the International Conference on Harmonisation (ICH) guidelines and proved to be robust. The LOD and LOQ for R-(+)pantoprazole were 0.2 and 0.5 microg/mL, respectively, with 5 microL injection volume. A good linear relationship was obtained in the concentration range of 0.5-6.0 microg/mL with r(2) >0.999 for R-(+)pantoprazole. The percentage recovery of the R-(+)pantoprazole ranged from 92.1 to 101.2 in bulk drug of S-(-)pantoprazole. The method is capable of determining a minimum limit of 0.05% w/w of R-enantiomer in S-(-)pantoprazole bulk samples.     

Liquid chromatography determination of citalopram enantiomers using beta-cyclodextrin as a chiral mobile phase additive

A reliable and specific method for the determination of citalopram enantiomers was developed and validated. Chromatographic resolution of citalopram enantiomers was made on a Shim-pack (5 microm particle size) cyanopropyl column with beta-cyclodextrin (beta-CD) as an effective chiral mobile phase additive. The composition of the mobile phase was (90 + 10, v/v) aqueous 0.1% triethylammonium acetate buffer, pH 4.0 (adjusted with acetic acid), and acetonitrile, containing 12 mM beta-CD. The flow rate was 0.8 mL/min with ultraviolet detection at 240 nm. The effects of the mobile phase composition, concentration of beta-CD, and pH of the triethylammonium acetate buffer on peak shape and resolution of the enantiomers were investigated. The calibration graphs were linear (r = 0.9999, n = 8) in the range of 1-40 microg/mL for S(+) citalopram and R-(-) citalopram. The limit of detection values were 5.51 x 10(-3) and 4.35 x 10(-3) pg/mL, while the limit of quantification values were found to be 1.84 x 10(-2) and 1.45 x 10(-2) microg/mL for S-(+) citalopram and R-(-) citalopram, respectively.     

Antimicrobial Constituents from Machaerium Pers.: Inhibitory Activities and Synergism of Machaeriols and Machaeridiols against Methicillin-Resistant Staphylococcus aureus,Vancomycin-Resistant Enterococcus faecium,and Permeabilized Gram-Negative Pathogens

Two new epimeric bibenzylated monoterpenes machaerifurogerol (1a) and 5-epi-machaerifurogerol (1b), and four known isoflavonoids (+)-vestitol (2), 7-O-methylvestitol (3), (+)-medicarpin (4), and 3,8-dihydroxy-9-methoxypterocarpan (5) were isolated from Machaerium Pers. This plant was previously assigned as Machaerium multiflorum Spruce, from which machaeriols A-D (6–9) and machaeridiols A-C (10–12) were reported, and all were then re-isolated, except the minor compound 9, for a comprehensive antimicrobial activity evaluation. Structures of the isolated compounds were determined by full NMR and mass spectroscopic data. Among the isolated compounds, the mixture 10 + 11 was the most active with an MIC value of 1.25 μg/mL against methicillin-resistant Staphylococcus aureus (MRSA) strains BAA 1696, −1708, −1717, −33591, and vancomycin-resistant Enterococcus faecium (VRE 700221) and E. faecalis (VRE 51299) and vancomycin-sensitive E. faecalis (VSE 29212). Compounds 6–8 and 10–12 were found to be more potent against MRSA 1708, and 6, 11, and 12 against VRE 700221, than the drug control ciprofloxacin and vancomycin. A combination study using an in vitro Checkerboard method was carried out for machaeriols (7 or 8) and machaeridiols (11 or 12), which exhibited a strong synergistic activity of 12 + 8 (MIC 0.156 and 0.625 µg/mL), with >32- and >8-fold reduction of MIC’s, compared to 12, against MRSA 1708 and −1717, respectively. In the presence of sub-inhibitory concentrations on polymyxin B nonapeptide (PMBN), compounds 10 + 11, 11, 12, and 8 showed activity in the range of 0.5–8 µg/mL for two strains of Acinetobacter baumannii, 2–16 µg/mL against Pseudomonas aeruginosa PAO1, and 2 µg/mL against Escherichia coli NCTC 12923, but were inactive (MIC > 64 µg/mL) against the two isolates of Klebsiella pneumoniae.     

Porphyrin Clathrates. Crystal Structures of Two Unexpected Products Obtained by Solvothermal Reactions of Pt-tetra(4-carboxyphenyl)porphyrin with Copper Acetate

The X-ray crystal structure of IX, perchlorate salt of R-(–-2-ethyl-N-benzyl-4,7,19,13-tetraoxa-8,9-benzo-1-azacyclopentadec-8-ene has been determined. In the molecule, the protonated nitrogen atom participates in two N-HO hydrogen bonds. The unusually high proton affinity of aza crown ether leads to the formation of diastreomer instead of complex formation with chiral R-(+)-1-phenyl ethyl ammonium perchlorate and S-(–)-1-phenyl ethyl ammonium perchlorate. The complex ability of host ethers was evaluated in terms of structural modification.     

Enantiomeric separation and quantification of pindolol in human plasma by chiral liquid chromatography/tandem mass spectrometry using staggered injection with a CTC Trio Valve system

Pindolol is a non-selective beta-adrenergic antagonist (beta-blocker) for the treatment of cardiovascular diseases such as hypertension and angina pectoris. It has one chiral center, and, therefore, two optical isomers. It was essential to develop an enantioselective assay to measure each enantiomer in human plasma. However, separation of enantiomers using chiral chromatography usually requires relatively long retention times. This can pose a problem for rapid turnaround of a large number of samples (i.e., clinical studies). In the present study, a simple and sensitive chiral liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) method was developed and validated for the determination of S-(-)- and R-(+)-pindolol in human plasma. To increase throughput, staggered sample injection was employed using a CTC Trio Valve system on a CTC HTS PAL autosampler. The method exhibited good intra- and inter-day accuracy and precision, and was linear over a dynamic range of 250 pg/mL to 250 ng/mL for each pindolol enantiomer. Intra- and inter-day accuracy ranged between 90.0-106% and 91.6-104% for both quality control (QC) samples of S-(-)- and R-(+)-pindolol, respectively. The respective intra- and inter-day precision ranged between 4.24-7.86% and 4.98-10.4%.     

纤维素-三（3,5-二甲苯基氨基甲酸酯）手性固定相拆分氨鲁米特对映体

以纤维素-三（3,5-二甲苯基氨基甲酸酯）为手性固定相（Chiralcel OD-H）在高效液相色谱上拆分了氨鲁米特对映体。通过测定氨鲁米特在正己烷/乙醇和正己烷/异丙醇中的溶解度,优选了对样品溶解度大的流动相体系,并考察了流动相添加剂乙醇胺对拆分效果的影响。在此基础上进一步研究了流动相中乙醇含量、柱温和进样量对分离因子、分离度、不对称因子和理论板数的影响,从而确定了最佳的拆分条件：固定相为Chiralcel OD-H,流动相为正己烷/乙醇/乙醇胺（体积比为30：70：0.1）,柱温25℃。本文所得结果可为工业放大提供基础数据。     

Separation of 2-naphthol atropisomers on cyclofructan-based chiral stationary phases

A set of fifteen 2-naphthol-derived atropisomers were evaluated on three different cyclofructan-based chiral stationary phases (CSP). The cyclofructan CSPs were a dimethylphenyl-derivatized cyclofructan 7 (CF7-DMP), a isopropyl (CF6-P) and a R-naphthylethyl cyclofructan 6 (CF6-RN) derivative, all bonded to 5-µm spherical fully porous silica particles packed into three 25?cm?×?4.6?mm columns (commercially available as Larihc columns). The 15 atropisomers were analyzed in the normal-phase mode with heptane/alcohol mobile phases. The CF7-DMP column was the most effective partially or fully separating 14 of the 15 compounds (93%). All 15 compounds could be separated by at least one cyclofructan column. Five compounds could be partially or fully separated by all three CSPs. The effect of ethanol, 2-propanol and butanol as 5 and 10% v/v polar modifiers in heptane was studied. A prototype 15?cm?×?4.6?mm column packed with superficially porous 2.7?µm CF6-P bonded particles was tested with the same set of compounds and a standard HPLC system. The increased efficiency and solvent saving were significant.     

Chiral analysis of baclofen by alpha-cyclodextrin-modified capillary electrophoresis and laser-induced fluorescence detection

An enantioselective method for baclofen (4-amino-3-p-chlorophenylbutyric acid) based on capillary electrophoresis (CE) separation and laser-induced fluorescence (LIF) detection has been developed. Naphthalene-2,3-dicarboxaldehyde (NDA) was used for precolumn derivatization of the nonfluorescent drug. alpha-Cyclodextrin (alpha-CD) was included in the buffer as a chiral selector for the separation of NDA-labeled S-(+)- and R-(-)-baclofen. Optimal resolution and detection were obtained with an electrophoretic buffer of 50 mM sodium borate (pH 9.5) containing 7 mM alpha-CD and a He-Cd laser (lambda ex = 442 nm, lambda em = 500 nm). Combined with a simple cleanup procedure, this method can be applied to the analysis of baclofen enantiomers in human plasma. The relative standard deviation (RSD) values on peak areas of a plasma sample containing 1.0 microM racemic baclofen were 6.4 and 4.9% (n = 8) for the S-(+)- and R-(-)-enantiomer, respectively. The RSD value on migration times of both enantiomers was 0.5% (n = 8). Calibration graphs for S-(+)- and R-(-)-baclofen in plasma showed a good linearity (r > or = 0.999) in the concentration range of 0.1-2.0 microM. The limit of detection of baclofen in plasma was about 10 ng/mL.     

Rapid and economic chiral-HPLC method of nebivolol enantiomers resolution in dosage formulation

A fast, economic, reproducible, accurate, effective, rugged and selective chiral-HPLC method was developed and validated for the enantiomeric resolution of nebivolol enantiomers [(+)-RRRS and (-)-SSSR)] in dosage formulation. The method was rapid as chiral separation occurred within only 12 min. The mobile phase used was n-heptane-ethanol-DEA (85:15:0.1, v/v) at 3.0 mL/min flow-rate with 225 nm detection. The column used was an amylase-based 3-AmyCoat (150 × 46 mm) [tris-(3,5-dimethylphenyl carbamate)]. The capacity factors of (+)-RRRS and (-)-SSSR enantiomers were 7.85 and 10.90 while the separation and resolution factors were 1.39 and 1.83, respectively. The limits of detection and quantitation for (+)-RRRS enantiomer were 4.5 and 10.00 μg/mL, while these values for (-)-SSSR enantiomer were 4.1 and 8.2 μg/mL, respectively. The linearity was observed in the concentrations range of 0.10-1.0 mg/mL for both enantiomers. The π-π interactions, hydrogen bonds, dipole-dipole interactions and steric effects control the chiral resolution of nebivolol enantiomers on the reported chiral column. The reported method can be used for the quality control of nebivolol in pharmaceutical preparations with good economy. In addition, this method can also be used for the analysis of (+)-RRRS and (-)-SSSR) enantiomers in biological and environmental samples.     

高效液相色谱-串联质谱法分析毛发中甲基苯丙胺和苯丙胺手性对映异构体

建立了高效液相色谱-串联质谱（HPLC-MS/MS）分析毛发中甲基苯丙胺与苯丙胺对映异构体的手性分离方法。采用SUPELCO Astec CHIROBIOTIC^® V2手性液相色谱柱,以甲醇-含0.1%（v/v）甲酸的20 mmol/L乙酸铵水溶液（99：1,v/v）为流动相进行手性分离。结果表明,甲醇高温水浴超声法能较好地提取苯丙胺类化合物,且峰形较好（拖尾因子>0.95）。S-（+）-甲基苯丙胺、R-（-）-甲基苯丙胺、S-（+）-苯丙胺和R-（-）-苯丙胺在15~300 ng/mg范围内线性关系良好,相关系数均大于0.99;甲基苯丙胺和苯丙胺的检出限分别为0.1 ng/mg和0.15 ng/mg,定量限分别为0.4 ng/mg和0.5 ng/mg;日内精密度均≤6.8%,日间精密度均≤11.4%。采用所建方法对50余嫌疑人毛发进行手性分析,检出单一S-（+）-甲基苯丙胺和S-（+）-苯丙胺的占70%,同时检出S-（+）-甲基苯丙胺、R-（-）-甲基苯丙胺、S-（+）-苯丙胺和R-（-）-苯丙胺的占18%。该法简单快速,精密度好,可为实际法医毒物鉴定案例中的毛发手性分析提供技术支持与科学依据。     

Enantiospecific high-performance liquid chromatographic assay with fluorescence detection for the monoamine oxidase inhibitor tranylcypromine and its applicability in pharmacokinetic studies.

In order to be able to measure low concentrations of tranylcypromine enantiomers in biological material, chiral fluorescent derivatization and high-performance liquid chromatography (HPLC) were employed. The internal standard S-(+)-amphetamine and borate-sodium hydroxide buffer pH 11 were added to plasma or urine sample aliquots. o-Phthaldialdehyde was used for precolumn derivatization in combination with the chiral mercaptan N-acetylcysteine. HPLC resolution of the diastereoisomeric derivatives was possible on an octadecylsilane column. The mobile phase consisted of sodium phosphate buffer solution pH 6.5, methanol and tetrahydrofuran. The fluorescence of the eluate was monitored at 344/442 nm. The intra-day coefficients of variation were below 10%, the limit of determination was 0.5 ng/ml. The assay was found to be applicable for routine analyses in a preliminary pharmacokinetic study, in which an oral dose of 20 mg racemic tranylcypromine sulfate was administered to three healthy volunteers. The plasma concentrations were generally low, and those of S-(-)-tranylcypromine significantly exceeded those of the R-(+)-enantiomer. Average maximum concentrations were 57.5 and 6.3 ng/ml for S- and R-tranylcypromine, respectively. While S-tranylcypromine was well detectable within the whole study period (8 h), R-tranylcypromine concentrations fell below the detection limit after 4 h in two out of the three studied volunteers.     

Simultaneous Determination of Human Serum Albumin and Low-Molecular-Weight Thiols after Derivatization with Monobromobimane

Biothiols are extremely powerful antioxidants that protect cells against the effects of oxidative stress. They are also considered relevant disease biomarkers, specifically risk factors for cardiovascular disease. In this paper, a new procedure for the simultaneous determination of human serum albumin and low-molecular-weight thiols in plasma is described. The method is based on the pre-column derivatization of analytes with a thiol-specific fluorescence labeling reagent, monobromobimane, followed by separation and quantification through reversed-phase high-performance liquid chromatography with fluorescence detection (excitation, 378 nm; emission, 492 nm). Prior to the derivatization step, the oxidized thiols are converted to their reduced forms by reductive cleavage with sodium borohydride. Linearity in the detector response for total thiols was observed in the following ranges: 1.76–30.0 mg mL⁻¹ for human serum albumin, 0.29–5.0 nmol mL⁻¹ for α-lipoic acid, 1.16–35 nmol mL⁻¹ for glutathione, 9.83–450.0 nmol mL⁻¹ for cysteine, 0.55–40.0 nmol mL⁻¹ for homocysteine, 0.34–50.0 nmol mL⁻¹ for N-acetyl-L-cysteine, and 1.45–45.0 nmol mL⁻¹ for cysteinylglycine. Recovery values of 85.16–119.48% were recorded for all the analytes. The developed method is sensitive, repeatable, and linear within the expected ranges of total thiols. The devised procedure can be applied to plasma samples to monitor biochemical processes in various pathophysiological states.