Journal of chromatographic science最新文献

In this work, a magnetic adsorption material based on metal-organic framework (Fe3O4@ZnAl-LDH@MIL-53(Al)) was synthesized and used as an adsorbent in the process of magnetic solid phase extraction. Then, a high-performance liquid chromatograph was used to quantitatively detect triazole fungicides in samples. In order to verify the successful preparation of the material, a series of characterization analyses were carried out. Besides, the key parameters that may affect the extraction efficiency have been optimized, and under optimal conditions the three triazole fungicides showed good linearity in the range of 10-1000 μg/L (R2 ≥ 0.9796); Limit of detections were ranged from 0.013 to 0.030 μg/mL. Finally, the established method was applied to the detection of triazole fungicides in four fresh juice samples. The results showed that the target analyte was not detected in all the test samples. By detecting the recoveries (73.3-104.3%) and coefficient variation (RSD ≤ 6.8%) of triazole fungicides in fortified samples, it proved that this established method meets the requirements of pesticide residue analysis and showed excellent application potential.

The combination of teneligliptin hydrobromide hydrate and pioglitazone hydrochloride in pharmaceutical formulations has improved type 2 diabetes management. Two chromatographic methods TLC-densitometry and RP-HPLC were developed for simultaneous quantification of teneligliptin hydrobromide hydrate and pioglitazone hydrochloride in pharmaceutical formulations, ensuring accuracy and stability assessment. The TLC method uses a mobile phase of methanol, toluene, ethyl acetate and triethylamine (1:7:2:0.1, v/v/v/v) on TLC silica gel plates, scanned at 268 nm. The RP-HPLC method employs isocratic elution with acetonitrile and sodium acetate buffer (adjust pH 3.6 with glacial acetic acid, 60:40 v/v) on a shimpack C18 column (250 × 4.6 mm i.d., 5 μm), detected at 235 nm. Both methods offer high accuracy and reliability, making them valuable for pharmaceutical quality control. Additionally, an environmental impact assessment was conducted using eco-scale, Analytical Greenness Metric Approach, Green Analytical Procedure Index, and national environmental method index to evaluate solvent consumption, waste generation and energy usage. Statistical comparisons (t-tests and F-tests) validate the outcomes of both methods, ensuring their effectiveness in drug formulation analysis. These methods can enhance pharmaceutical quality control while fulfilling environmental responsibilities.

A sensitive, specific, reliable and low-cost LC-UV method has been developed and validated for simultaneous quantification of brimonidine tartrate (BM) and brinzolamide (BZ) in rabbit aqueous humor (AH) in the presence of N-desethyl-brinzolamide (NDBZ); BZ is a major degradation product, and it is also considered to be its major metabolite. Dorzolamide hydrochloride (DZ) was used as an internal standard (IS). The analytes were extracted from rabbit AH samples by a simple pre-treatment utilizing ZnSO4.7H2O as a deproteinizing agent. The analytes were separated on a cyanopropyl Waters column (4.6 × 200 mm, 5 μm) with an isocratic mobile phase consisting of 25 mM ammonium acetate pH 4.5 (adjusted with 85% phosphoric acid):methanol:acetonitrile (94:4.5:1.5, v/v) at a flow rate of 1.0 mL min-1. The detection was done at 254 nm. The lower limit of quantification in rabbit AH was 100.0 ng mL-1. The method was validated according to EMA guidelines. The method was confirmed to be accurate, precise and linear over a range of 100.0-1000.0 ng mL-1 for BM and BZ. The method developed herein is simple, safe, eco-friendly, rapid and accurately applied for the quantification of BM and BZ, along with the successful separation of NDBZ, which is considered as a potential irritant degradation product of BZ.

Recently, the demand for respiratory disease-related products has surged due to the influence of coronavirus disease 2019, prompting warnings about illegal dietary supplements containing unauthorized substances. Additionally, adulterated dietary supplements are continuously detected in open markets, posing significant public health safety problem. In this study, we developed and validated an analytical method for 11 respiratory drug substances using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) and proposed optimal conditions for LC-quadrupole time-of-flight MS (LC-QTOF-MS) to determine the fragmentation patterns of each substance. This method underwent thorough validation considering specificity, linearity, limits of detection and quantification, accuracy, precision, matrix effect, stability, etc. All results met international guidelines. These validated methods were applied to 52 dietary supplements advertised for treating respiratory diseases and enhancing respiratory function, among which one sample was found to contain 313.7 mg/g of theobromine. This determination was made by comparing the product ion ratios with the standards and subsequent quantification. To re-confirm the detected substances, their fragmentation patterns were compared with those of the standards using LC-QTOF-MS. In conclusion, the mass-based information, coupled with the LC-ESI-MS/MS method development, can be successfully applied to rapidly identify 11 respiratory drug substances in illegal dietary supplements used for respiratory disease treatment. The developed simultaneous detection method contributes to public health and safety improvements.

The concentration of mitoxantrone in the blood of mice was determined by a high-performance liquid chromatography-ultraviolet method with aloe-emodin as the internal standard. The separation was performed on a Hypersil BDS2 column (4.6 × 250 mm, 5 μm) as the analytical column, the mobile Phase A was acetonitrile, and B was 20-mM potassium dihydrogen phosphate (adding 1% triethylamine and adjusting the pH to 2.8 with phosphoric acid) and 4.6-mM sodium octyl sulfonate. The flow rate was 1.0 mL·min-1, the detection wavelength was 243 nm, the column temperature is 25 ± 5°C and the injection amount was 20 μL. Finally, the linear range of mitoxantrone was 5-200 μg·mL-1, and the correlation coefficient was r = 0.9999. The recovery rate of the method was 91.93-105.5%, and the extraction recovery rate was 91.45-105.5%. The intraday precision and interday precision were <3.29% (limit of detection = 0.3 μg·mL-1). The HPLC method established in this paper was simple, rapid, sensitive and accurate, and can be used to determine the content of mitoxantrone in mouse plasma after tail vein injection.

The combination of the tricyclic antidepressant amitriptyline hydrochloride (AMH) and the non-selective beta-adrenergic blocker propranolol hydrochloride (PPH) is used for migraine prophylaxis. Higher doses of AMH trigger cardiac arrhythmias, anxiety, tachycardia, convulsions, hyperglycemia and anticholinergic side effects. The combined dosage formulation of AMH and PPH leads to drug-drug interactions; causes sedation, xerostomia, dysuria, insomnia and bradycardia; and results in patient non-compliance. The quantification of AMH and PPN becomes essential, especially for combination formulations, in addition to regular quality control to avoid clinical issues. Considering these facts into account, the reverse-phase -high-performance liquid chromatography (RP-HPLC) method was developed in accordance with International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use Q2(R1) guidelines for the simultaneous determination of AMH and PPH. The HPLC separation was performed on an HPLC system (Shimadzu, Japan, Prominence I series 2030C) using a Shimadzu Shim-Pack GIST C18 column (100 mm × 4.6 mm, 5 μ), which was equipped with an ultraviolet detector at the isosbestic point 238 nm. The mixture of acetonitrile and orthophosphoric acid (pH 3.5) in a ratio of 35:65 v/v with a flow rate of 0.75 mL/min was used as the mobile phase. The regression coefficients of AMH (r2 > 0.998) and PPH (r2 > 0.999) show good linearity between peak areas and drug concentration ranges. The limits of detection (AMH = 0.67 μg/mL, PPH = 0.67 μg/mL) and limits of quantification (AMH = 2.04 μg/mL, PPH = 2.05 μg/mL) demonstrated the higher detection sensitivity of the proposed method.

Cancer is considered a silent killer. The complexity of cancer makes it earn that title. So far there are only a few approaches to treat cancer. Among them, chemotherapy is considered the best approach. Many chemotherapeutical compounds are commercially available in the market. Among them, doxorubicin (DOX) and lapatinib (LAP) are considered blockbuster molecules. However, DOX suffers from poor bioavailability and exhibits cardiotoxicity. Interestingly, a fixed dose combination of DOX and LAP significantly decreases the cardiotoxic effect of DOX. To enhance the oral bioavailability of DOX and to avail the synergistic effect of LAP, many formulations have been made. To quantify both compounds in any formulation or biological matrix, an Liquid chromatography-Mass Spectrometry (LC-MS) method is required. In this present study, a simple and rapid Ultra High-Performance Liquid Chromatography - Heated Electron Spray Ionization - Mass Spectrometry (UHPLC-HESI-MS) bioanalytical method was developed. The developed method was validated as per the regulatory guidelines. The validated bioanalytical method had a lower limit of quantification of 0.75 ng. A simple protein precipitation technique was optimized to extract the compounds from the rat plasma. All the validation parameters were found to be within the limits as per the regulatory guidelines. A novel and rapid analytical method was successfully developed and validated. This developed method can be used to quantify the DOX and LAP in any formulation and biological matrix.

Ibrutinib is an orally administered compound that functions as an irreversible covalent inhibitor of the Bruton tyrosine kinase, an essential element in multiple cellular processes including B-cell differentiation, proliferation, migration, survival and apoptosis. The compound has been found to demonstrate efficacy against a range of B-cell malignancies. The drug product is available in oral tablet and capsule formulations. The drug degradation profiles of tablets dosage form were assessed in accordance with regulatory guidelines. The results indicate that the drug substance is susceptible to alkaline and oxidative stress. The oxidation degradation led to the identification of three significant unknown degradation impurities. The three compounds were isolated through the application of preparative liquid chromatography, and their structures were determined using analytical techniques such as liquid chromatography-mass spectrometry, high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. Utilizing structural elucidation data, predictions were made regarding the composition of impurities, revealing them to be novel degradation impurities that bear structural resemblance to ibrutinib. Additionally, potential pathways for the formation of the impurities were proposed.