Simultaneous determination of triazole antifungal drugs in human plasma by sweeping-micellar electrokinetic chromatography

Triazoles in the environment: An update on sample pretreatment and analysis methods

Triazoles, due to their high bactericidal performance, have been widely used in the agricultural, clinical, and chemical industry. However, triazoles have been proven to cause endocrine-toxic and organ impairment in humans as a potentially toxic substance. Besides, because of the improper use and difficulty of degradation, triazoles pesticide residues left in the environment could pose a threat to the environment. Therefore, the rapid, reliable, accurate, and high-sensitivity triazoles analysis methods are significantly essential to effectively monitor their presence in various samples and safeguard human health. This review aims to summarize and update the progress of the pretreatment and analytical methods of triazole fungicides in environmental samples from 2012 to 2024. Common pretreatment methods used to extract and purify targets include simple steps (e.g., protein precipitation and coated blade spray), liquid-liquid extraction, solid-phase extraction, and various microextraction methods such as liquid-phase microextraction and solid-phase microextraction, among others. Detection methods mainly include liquid chromatography-mass spectrometry, gas chromatography-mass spectrometry, supercritical fluid chromatography, sensing methods, and capillary electrophoresis. In addition, we elaborate and compare the advantages and disadvantages of different pretreatment and analytical methods, and their development prospects are discussed.

Electromembrane Extraction of Posaconazole for Matrix-Assisted Laser Desorption/Ionization Mass Spectrometric Detection

A new mode of electromembrane extraction (EME) has been developed for detection via matrix-assisted laser desorption/ionization mass spectrometry (MALDI/MS). Posaconazole, extracted from 8 mL of a 10 mM trifluoroacetic acid solution onto a thin polyvinylidene difluoride (PVDF) membrane, was used as a model analyte. The transport was forced by an electrical potential difference between two electrodes inside the lumen of a hollow fiber and glass tube. Under an application of 80 V, cationic posaconazole in the sample solution moved toward the negative electrode inside the glass tube and was trapped by the PVDF membrane on the side. After 15 min of extraction, 3 μL of α-cyano-4-hydroxycinnamic acid (CHCA) solution was applied on top of the membrane, which was then analyzed by MALDI/MS. Under optimal extraction conditions, the calibration curve of posaconazole was linear over a concentration range of 0.10-100.00 nM. The limit of detection (LOD) at a signal-to-noise ratio of 3 was 0.03 nM with an enhancement factor of 138 for posaconazole. The application of this method to the determination of posaconazole in human serum samples was also successfully demonstrated.

Influence of Organic Solvents and β-cyclodextrins on Capillary Zone Electrophoresis Separation of Five Biogenic Amines and Two B Vitamins

The effects of organic modifiers—alcohols (methanol, isopropanol), acetonitrile, and tetrahydrofuran—and β-cyclodextrins in capillary zone electrophoresis were investigated using a test mixture containing five biogenic amines important from the human health point of view—serotonin, dopamine, adrenaline, noradrenaline, and tyramine—and two B vitamins—thiamine and pyridoxine. The simultaneous addition of tetrahydrofuran and isopropanol was found to improve the resolution of determined analytes and enable effective separation of analytes with very similar electromigration characteristics migrating as one peak (dopamine and serotonin). The developed and optimised separation method based on capillary zone electrophoresis and ultraviolet detection was capable to achieve detection limits at the concentration level in the range of 0.15 to 1.25 μg/mL−1. The developed method was also characterised by other favourable validation parameters, such as linearity (r 2 > 0.99), accuracy (82.9–117.8% for the intraday measurements, and 87.6–119.2% for the interday measurements), and precision (intraday relative standard deviation in the range of 0.4–15.5%, interday relative standard deviation in the range of 0.9–18.3%). The method was finally applied to investigate the stability of the analytes in model water matrix samples under various storage conditions.

Micellar electrokinetic chromatography in the determination of triazoles in fruit peel

Triazole fungicides (TAFs) are frequently used fungicides for various antifungal treatments of crops. Tre treatment is provided foliarly. However, some significant amount of TAFs may remain on/in fruits. We have developed a methodology for the determination of penconazole, tebuconazole and cyproconazole in tomato fruit peel. The extraction of TAFs was provided with chloroform (acidified with 0.1% acetic acid). In the electrokinetic chromatography, the mixed micellar pseudo-stationary phase was composed of anionic detergent sodium dodecyl sulphate (15 mM) and randomly highly sulphated gamma-cyclodextrin (17.5 mg/mL). The background electrolyte consisted of 100 mM phosphoric acid and 100 mM Tris in the mixed hydro-organic solvent water/methanol (80/20 v/v), apparent pH 4.8. Complete separation of penconazole, tebuconazole, and two diastereomers of cyproconazole with resolutions higher than 5.1 were achieved within a relatively short time of less than 17 min in the bare fused silica capillary of 425/500 mm total/effective lengths and 50/375 μm I.D./O.D. at separation voltage -15 kV (cathode at injection capillary end) and at constant capillary cassette temperature of 22°C. The TAFs were detected by a UV-spectrophotometric diode array detector set at 200 nm. The limits of detection and limits of quantification were in the range of 71-92 and 214-278 μg/kg of peel, respectively. Analyses of the peel extracts revealed that even 10 days after the last treatment, TAF concentrations were higher than the recommended maximum residue limits in both application ways, as individual as well as in the TAF binary or ternary mixtures.

Application of HPTLC, spectrofluorimetry and differential pulse voltammetry for determination of the antifungal drug posaconazole in suspension dosage form

This work presents the development, validation and application of three simple and direct analytical methods for determination of posaconazole (PSZ) in its pure form and in suspension dosage form. Method I is based on high performance thin layer chromatography (HPTLC) where effective separation of PSZ and the internal standard (itraconazole) was achieved using Merck HPTLC plates (20×10cm aluminium plates with 250μm layer thickness precoated with silicagel 60 F₂₅₄) and a mobile phase composed of acetone and chloroform (1:2, by volume), followed by densitometric measurement of the drugs' spots at 262nm. Method II involves measurement of the native fluorescence of PSZ in 0.1M H₂SO₄ at excitation and emission wavelengths of 260 and 365nm, respectively. Method III depends on the voltammetric analysis of PSZ. A well-defined cathodic wave was obtained for PSZ in Britton-Robinson buffer pH 6.5 using the differential-pulse mode at the hanging mercury drop electrode (HMDE). The developed methods were validated according to the International Conference on Harmonization (ICH) guidelines regarding linearity, ranges, accuracy, precision, robustness and limits of detection and quantification. The proposed methods showed good linearity over the concentration ranges 5-50, 0.05-0.3, 0.005-0.05μg/mL PSZ for methods I, II, and III respectively. Intra and inter-day precision were verified by the RSD% values which were less than 2%. The proposed methods were successfully applied for the quantification of PSZ in suspension dosage form with no observable interferences. Assay methods were favorably compared with those obtained by previously reported HPLC method.

High Performance Liquid Chromatographic Assay for the Simultaneous Determination of Posaconazole and Vincristine in Rat Plasma

Purpose. Developing a validated HPLC-DAD method for simultaneous determination of posaconazole (PSZ) and vincristine (VCR) in rat plasma. Methods. PSZ, VCR, and itraconazole (ITZ) were extracted from 200 μL plasma using diethyl ether in the presence of 0.1 M sodium hydroxide solution. The organic layer was evaporated in vacuo and dried residue was reconstituted and injected through HC-C18 (4.6 × 250 mm, 5 μm) column. In the mobile phase, acetonitrile and 0.015 M potassium dihydrogen orthophosphate (30 : 70 to 80 : 20, linear gradient over 7 minutes) pumped at 1.5 mL/min. VCR and PSZ were measured at 220 and 262 nm, respectively. Two Sprague Dawley rats were orally dosed PSZ followed by iv dosing of VCR and serial blood sampling was performed. Results. VCR, PSZ, and ITZ were successfully separated within 11 min. Calibration curves were linear over the range of 50–5000 ng/mL for both drugs. The CV% and % error of the mean were ≤18% and limit of quantitation was 50 ng/mL for both drugs. Rat plasma concentrations of PSZ and VCR were simultaneously measured up to 72 h and their calculated pharmacokinetics parameters were comparable to the literature. Conclusion. The assay was validated as per ICH guidelines and is appropriate for pharmacokinetics drug-drug interaction studies.

Therapeutic drug monitoring for triazoles: A needs assessment review and recommendations from a Canadian perspective

Invasive fungal infections cause significant morbidity and mortality in patients with concomitant underlying immunosuppressive diseases. The recent addition of new triazoles to the antifungal armamentarium has allowed for extended-spectrum activity and flexibility of administration. Over the years, clinical use has raised concerns about the degree of drug exposure following standard approved drug dosing, questioning the need for therapeutic drug monitoring (TDM). Accordingly, the present guidelines focus on TDM of triazole antifungal agents. A review of the rationale for triazole TDM, the targeted patient populations and available laboratory methods, as well as practical recommendations based on current evidence from an extended literature review are provided in the present document.

Hollow fiber based liquid–liquid–liquid microextraction combined with sweeping micellar electrokinetic chromatography for the sensitive determination of second-generation antidepressants in human fluids

HF-LPME is combined with sweeping MEKC for the sensitive determination of second-generation antidepressants in human fluids.

A Comparative Study of Newly Developed HPLC-DAD and UHPLC-UV Assays for the Determination of Posaconazole in Bulk Powder and Suspension Dosage Form

Objective. To develop and compare HPLC-DAD and UHPLC-UV assays for the quantitation of posaconazole in bulk powder and suspension dosage form. Methods. Posaconazole linearity range was 5-50 μg/mL for both assays. For HPLC-DAD assay, samples were injected through Zorbax SB-C18 (4.6 × 250 mm, 5 μm) column. The gradient elution composed of the mobile phase acetonitrile: 15 mM potassium dihydrogen orthophosphate (30 : 70 to 80 : 20, linear over 7 minutes) pumped at 1.5 mL/min. For UHPLC-UV assay, samples were injected through Kinetex-C18 (2.1 × 50 mm, 1.3 μm) column. The mobile phase composed of acetonitrile: 15 mM potassium dihydrogen orthophosphate (45 : 55) pumped isocratically at 0.4 mL/min. Detection wavelength was 262 nm in both methods. Results. The run time was 11 and 3 minutes for HPLC-DAD and UHPLC-UV assays, respectively. Both assays were linear (r (2) > 0.999) with CV% and % error of the mean <3%. Limits of detection and quantitation were 0.82 and 2.73 μg/mL for HPLC-DAD and 1.04 and 3.16 μg/mL for UHPLC-UV, respectively. The methods quantitated PSZ in suspension dosage form with no observable interferences. Conclusions. Both assays were proven sensitive and selective according to ICH guidelines. UHPLC-UV assay exhibited some economic and chromatographic separation superiority.

Principles of micellar electrokinetic capillary chromatography applied in pharmaceutical analysis

Since its introduction capillary electrophoresis has shown great potential in areas where electrophoretic techniques have rarely been used before, including here the analysis of pharmaceutical substances. The large majority of pharmaceutical substances are neutral from electrophoretic point of view, consequently separations by the classic capillary zone electrophoresis; where separation is based on the differences between the own electrophoretic mobilities of the analytes; are hard to achieve. Micellar electrokinetic capillary chromatography, a hybrid method that combines chromatographic and electrophoretic separation principles, extends the applicability of capillary electrophoretic methods to neutral analytes. In micellar electrokinetic capillary chromatography, surfactants are added to the buffer solution in concentration above their critical micellar concentrations, consequently micelles are formed; micelles that undergo electrophoretic migration like any other charged particle. The separation is based on the differential partitioning of an analyte between the two-phase system: the mobile aqueous phase and micellar pseudostationary phase. The present paper aims to summarize the basic aspects regarding separation principles and practical applications of micellar electrokinetic capillary chromatography, with particular attention to those relevant in pharmaceutical analysis.