期刊,Journal of chromatography 2022年1204卷期_国家学术搜索

期刊信息/Journal information

Journal of chromatography

Elsevier

主办单位：Elsevier

国际刊号：1570-0232

Journal of chromatography/Journal Journal of chromatography

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Evaluation of hybrid surface technology for the analysis of the B-group vitamins by LC-ESI-MS/MS

Yang, JinchuanWilson, IanRainville, Paul

8页

查看更多>>摘要：Recently, a novel hybrid surface technology (HST) has been developed to mitigate metal analyte adsorption in liquid chromatography. The HST provides a hybrid organic-inorganic surface on the metal fluidic path, from injection to detector and including the column frits and wall, to mitigate the interaction between analytes and metals. Here the impact of the HST on the analysis of B group vitamins using liquid chromatography coupled with electrospray tandem mass spectrometry (LC-ESI-MS/MS) has been evaluated. Significant improvements in analyte intensity, limit of quantification (LOQ), carry-over, and peak shape were observed using an LC-ESI-MS/ MS system and column that incorporated the HST. The key observed improvements include a 3-10 times increase in sensitivity (providing a lower LOQ) for riboflavin, thiamine, nicotinamide, FMN, PLP, and 5MTHF, no carryover, and a more symmetrical peak for thiamine. When applied to the analysis of B group vitamins in energy drinks and B vitamin dietary supplement samples, the HST system demonstrated excellent accuracy and repeatability.

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NSTL
Elsevier

A mixed deep eutectic solvents-based air-assisted liquid-liquid microextraction of surfactants from exhaled breath condensate samples prior to HPLC-MS/MS analysis

Khoubnasabjafari, MaryamJouyban, AbolghasemHosseini, MohamadbagherFarajzadeh, Mir Ali...

7页

查看更多>>摘要：A ternary solvent system-based air-assisted liquid-liquid microextraction procedure was developed for the extraction of three surfactants from exhaled breath condensate samples prior to their determination by high performance liquid chromatography-tandem mass spectrometry. In this approach, different deep eutectic solvents were synthesized based on phosphocholine chloride and fatty acids and their mixtures were used as the extraction solvents to effective extraction of the analytes. To obtain the optimum composition of the extraction solvents, a simplex centroid design approach was used. Then the effective parameters were studied by response surface methodology using central composite design. The obtained data after optimization showed that 6 times was the best extraction time for the developed procedure. When the sample solution pH was adjusted at 3.7, the method reached to higher extraction efficiency which can be related to the fact that the analytes were in the protonated forms. Increasing the sample solution temperature up to 50 degrees C enhanced the migration rate of the analytes into the extraction solvent and the method efficacy was increased. Also addition of sodium chloride at 2.8% (w/v) had a positive effect on the method efficiency which can be related to decreasing the analytes solubility in the sample solution. Under optimal conditions, the method showed satisfactory coefficient of determination (>0.9979), low limit of detection (0.12-0.23 ng mL-1) and quantification (0.39-0.76 ng mL-1), acceptable repeatability in deionized water (relative standard deviation < 8.2%) and in exhaled breath condensate (relative standard deviation < 7.2%), and acceptable extraction recovery (75-86%) and enrichment factor (71-86). Considering these results, the developed method provided a quick and efficient way to determine surfactants in the exhaled breath condensate collected from expiratory circuit of the mechanical ventilator. It can be used in drug monitoring and clinical studies.

原文链接:

NSTL
Elsevier

Supercharging reagents in LC-MS/MS hormone analyses: Enhancing ionization, not limit of quantification

de Kleijne, Vera H.Heijboer, Annemieke C.de Jonge, RobertAckermans, Mariette T....

9页

查看更多>>摘要：One of the critical steps during LC-MS/MS hormone analyses that affects the sensitivity of the assay is the ionization process. Enhancing ionization efficiencies by the addition of supercharging reagents might be one way to improve sensitivity and reduce the limit of quantification (LOQ). Therefore, we investigated whether the addition of the supercharging reagents m-nitrobenzyl alcohol (m-NBA), sulfolane, propylene carbonate, and onitroanisole (o-NA) increased ionization efficiency and improved assay LOQ of insulin, oxytocin, sex steroids, and corticosteroids in test solutions. Additionally, the influence of the supercharging reagents was tested in serum samples after sample pretreatment to determine whether ionization would be enhanced similarly in routine analyses and, subsequently, lead to improved sensitivity. The screening experiments showed that the impact of the supercharging reagents varied for each hormone; although the addition of m-NBA increased the signal of all hormones, the other reagents only enhanced ionization efficiencies for some hormones. While the addition of 0.05 v/v% m-NBA and 0.05 v/v% o-NA did result in an increase in peak area in both test solutions and serum samples, it did not significantly improve the signal-to-noise ratio, as a simultaneous increase in noise was observed. In conclusion, even though supercharging reagents can enhance ionization efficiencies of hormones significantly, the addition of these reagents does not result in an improved LOQ for hormone measurements with LC-MS/MS.

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NSTL
Elsevier

Mono-PEGylated lysozyme purification with increased productivity and isomer differentiation through heparin monolith chromatography

Menjia-Manzano, Luis AlbertoCampos-Garcia, Victor R.Perdomo-Abundez, Francisco C.Medina-Rivero, Emilio...

8页

查看更多>>摘要：PEGylated protein purification with the required quality attributes has represented a bioengineering challenge and Affinity Monolith Chromatography (AMC) has never been exploited for this goal. This work reports the generation of a heparin-modified affinity monolith disk by reductive alkylation with raised ligand density for its use as chromatographic support in the separation of lysozyme PEGylation reactions (LPRs) with three different PEG sizes (1, 20 and 40 kDa). For immobilized heparin determination a modified toluidine colorimetric assay adapted to microplate format was proposed. The heparin modified-disk was able to differentiate positional isomers of 20 kDa mono-PEGylated lysozyme at neutral pH using a salt linear gradient. Identity of PEGconjugates was verified by SDS-PAGE and positional isomers were partially characterized by peptide mapping mass spectrometry. 20 kDa mono-PEGylated lysozyme conjugate purity (99.69 +/- 0.05%) was comparable with traditional chromatographic methods while productivity (0.0964 +/- 0.0001 mg/mL*min) was increased up to 6.1 times compared to that obtained in heparin packed-bed affinity chromatography procedures. The proposed AMC method represents a reliable, efficient, easy-handling, fast and single-step operation for the analysis or preparative isolation of PEGylated proteins containing a heparin binding domain.

原文链接:

NSTL
Elsevier

Determination of ions in Caenorhabditis elegans by ion chromatography

Moura, Alexandre VaraSilva, Alex Aparecido RosiniDa Silva, Jose Domingos SantoPedroza, Lucas Aleixo Leal...

6页

查看更多>>摘要：The Caenorhabditis elegans (C. elegans) is a model organism that has been increasingly used in health and environmental toxicity assessments. The quantification of such elements in vivo can assist in studies that seek to relate the exposure concentration to possible biological effects. Therefore, this study is the first to propose a method of quantitative analysis of 21 ions by ion chromatography (IC), which can be applied in different toxicity studies in C. elegans. The developed method was validated for 12 anionic species (fluoride, acetate, chloride, nitrite, bromide, nitrate, sulfate, oxalate, molybdate, dichromate, phosphate, and perchlorate), and 9 cationic species (lithium, sodium, ammonium, thallium, potassium, magnesium, manganese, calcium, and barium). The method did not present the presence of interfering species, with R2 varying between 0.9991 and 0.9999, with a linear range from 1 to 100 mu g L-1. Limits of detection (LOD) and limits of quantification (LOQ) values ranged from 0.2319 mu g L-1 to 1.7160 mu g L-1 and 0.7028 mu g L-1 to 5.1999 mu g L-1, respectively. The intraday and interday precision tests showed an Relative Standard Deviation (RSD) below 10.0 % and recovery ranging from 71.0 % to 118.0 % with a maximum RSD of 5.5 %. The method was applied to real samples of C. elegans treated with 200 uM of thallium acetate solution, determining the uptake and bioaccumulated Tl+ content during acute exposure.

原文链接:

NSTL
Elsevier

Development and validation of a gradient HPLC-UV method for mitragynine following in vitro skin permeation studies

Sim, Yee ShanChong, Zan YangAzizi, JuzailiGoh, Choon Fu...

13页

查看更多>>摘要：Mitragynine is a promising candidate for pain relief and opiate replacement but the investigations for drug delivery are lacking. This study aims to investigate the potential of mitragynine to be delivered through the skin with an emphasis on developing and validating a gradient HPLC-UV analytical method to determine mitragynine in the samples collected during in vitro skin permeation studies. The optimised method involves a gradient elution using a C18 column with a mobile phase comprising acetonitrile and 0.1 %v/v of formic acid (0-1 min: 30:70 to 70:30 (v/v) and hold up to 4 min; 4-6 min: return to 30:70 (v/v) and hold up to 10 min) at a flow rate of 1.2 mL/min. This method was validated based on the standards set by the International Council on Harmonisation guidelines. The method showed mitragynine elution at 4 min with adequate linearity (R-2 >= 0.999 for concentration ranges of 0.5-10 and 10-175 mu g/mL) and acceptable limits of detection and quantification at 0.47 and 1.43 mu g/mL, respectively. The analytical performance is robust with excellent precision and accuracy. This method was used to evaluate the in vitro skin permeation of mitragynine (5 %w/v) from simple solvent systems over 48 hr. The results showed a cumulative amount of mitragynine permeated at similar to 11 mu g/cm(2) for dimethyl sulfoxide and similar to 4 mu g/cm(2) for propylene glycol. The study not only addressed the issues of the currently available HPLC-UV methods that limit the direct application but also affirmed the potential of mitragynine to be delivered through the skin.

原文链接:

NSTL
Elsevier

High performance thin layer chromatography based chemo profiling of Ashvagandharishta and its antidepressant activity

Gupta, TinkuAeri, VidhuYadav, Ketan

11页

查看更多>>摘要：Withania somnifera (L.) has long been used as a traditional rasayana herb against a variety of human ailments. This research presents a high performance thin layer chromatography based chemo profiling of Ashva-gandharishta and its antidepressant activity. The in-house formulation was made using a fermentation process according to the Indian Pharmacopoeia. Physiochemical standardization of the formulation was performed using different quality control parameters such as total ash, acid insoluble ash, alcohol soluble extract value and water soluble extract value. A column chromatography and high performance thin layer chromatography method was used to isolate and estimation of withanolide-A, withaferin-A & beta-sitosterol from the root of W. somnifera. In addition. The antidepressant effect of different formulations were carried out by force swimming test in albino mice. The thiobarbituric acid reactive substances (TBARS) and Glutathione (GSH) assay was used to find out the oxidative stress. W. somnifera root has been standardized macroscopically, microscopically, physico-chemically according to the guidelines of the Ayurvedic Pharmacopoeia. The qualitative and quantitative analysis was performed using high performance thin layer chromatography and it was performed on each formulation and found the content of withanolide-A and-sitosterol in the in-house formulation is higher while withaferin-A is rather contained in the decoction. The antidepressant effect showed that the immobility time was lowest in the case of the standard formulation followed by in house formulation, while the increase in glutathione and the reduction in thiobarbituric acid reactive substances levels revealed the antioxidant nature of the formulation. In conclusion, based on the above results, we can conclude that Ashvagandharishta could be a breakthrough for the treatment of depression in the future.

原文链接:

NSTL
Elsevier