The chromatographic behavior of some basic and acidic drugs was studied on C18, Phenyl-Hexyl and Polar RP columns with methanol or acetonitrile as organic modifiers of aqueous mobile phases containing addition of diethylamine. Diethylamine plays a double function of silanol blocker reagent in analysis of basic drugs and ion-pair reagent in analysis of acidic drugs. Most symmetrical peaks and hi...

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 ...

In this study, optimization, extension, and validation of a streamlined, qualitative and quantitative multiclass, multiresidue method was conducted to monitor >100 veterinary drug residues in meat using ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Optimization centered on extensive ruggedness evaluation of the method. Various clean-up sorbents were tested ...

Introduction. To date, the use of unmanned aerial vehicles (UAVs) in Ukraine for agricultural lands treatment is a new promising technology that requires detailed study and development approaches to risk assessment hygienic regulation. Development method will allow measuring content diamond blue FCF sorption material (filter paper) relevant. The aim – determining synthetic dye by high-performan...

In this study, high performance liquid chromatography (HPLC) was used to analyze the protodioscin content in Tribulus terrestris samples. They were separated by C18 column, gradient with 0.1 % phosphoric acid solution and acetonitrile as mobile phase flow rate of 0.5 mL/min, column temperature 45 °C, detection wavelength 203 nm. The results showed that has a good linear correlation (r>0.999)...

Most methods for automated full-bore rock core image analysis (description, colour, properties distribution, etc.) are based on separate column analyses. The is usually imaged in a box because of the significant amount time taken to get an each column. work presents innovative method and algorithm columns extraction from boxes. conditions boxes imaging may differ tremendously. Such differences ...

A new fast screening method has been developed for the analysis of organochlorine pesticides in water that takes less than 10 min to perform and has detection limits of the order of 10 ng l21. Pesticide extraction was achieved by solid-phase microextraction and the separation was performed using a micro-bore (0.1 mm) capillary column. A laboratory-built cryotrap system was used to focus the ana...

The mechanism of degradation of dantrolene in aqueous buffer solutions was studied at various pH values in the range of pH 1.2 9.5 and at temperatures ranging from 25 ̊C to 75 ̊C to determine the optimum pH and temperature requirements for its stability and eventual product performance over the human gastrointestinal pH range. Dantrolene was analyzed by reversed phase ultra-performance liquid chr...