A gas chromatography multi-pesticide with an internal standard method has been developed to analyze simultaneously separate nine active ingredients (acephate, carbaryl, chlorpyrifos, chlorothalonil, diazinon, dimethoate, malathion, profenofos, quinalphos) in different commercial pesticide formulations. A mixture of pure standard solution spiked with 1-chloro-4fluorobenzene as the internal stand...

The aim of the study was to develop a bioanalytical method for the determination of temozolomide (TMZ) in human plasma. Plasma concentration of TMZ was determined on a C18 column after liquid-liquid extraction. Isocratic elution was applied with the mixture of aqueous acetic acid and methanol. Theophylline was used as the internal standard. To prevent chemical degradation of TMZ at physiologica...

This work reports the development of a fast chromatographic methodology for quantitation of two phytoestrogens: daidzein (DAI), and genistein (GEN), in river water samples. The proposed method is based on high performance liquid chromatography-diode array detection (HPLC-DAD) data, and multivariate curve resolution-alternative least square (MCR-ALS) second-order calibration. Initially, the meth...

A simple, rapid, and sensitive HPLC method was developed and validated to quantify Amphotericin B (AmB) in human plasma. AmB was extracted from spiked plasma by simple protein precipitation with methanol. The separation was performed on an XBridgeTM C18 (150 × 4.6 mm, 3.5 μm) column, with a mobile phase of acetic acid (0.73%) – acetonitrile (60:40, v/v) and at a flow rate of 1 mL/min. The elute...

A sensitive and selective method is needed to analyse in situ produced vitamin B12 in plant-based materials, potential new dietary sources of vitamin B12. A UHPLC/UV method was developed and validated for the determination of human active vitamin B12 in cell extracts of Propionibacterium freudenreichii subsp. shermanii and after immunoaffinity purification in extracts of cereal matrices ferment...

A high-performance liquid chromatography – tandem mass spectrometry (HPLC– MS–MS) method was developed for the determination of chloramphenicol (CAP) in milk products. Mass spectral acquisition was done using electrospray ionization in the negative ion mode applying multiple reaction monitoring of two diagnostic transition reactions for CAP (m/z 321→152 and m/z 321→257). Milk samples were extra...

An LC-MS/MS assay based on a signature peptide was developed and fully validated for the quantitation of bovine lactoferrin in infant formulas. Three unreported signature peptides were derived and identified from the tryptic peptides of bovine lactoferrin. The peptide ETTVFENLPEK was used for quantification based on assay performance. The blank matrix camel milk powder and bovine lactoferrin pr...

In the present work, a new ligandless-ultrasound-assisted emulsification microextraction (LL-USAEME) method was developed for preconcentration trace amounts of nickel as a prior step to its determination by flame atomic absorption spectrometry. Some factors influencing the extraction efficiency of nickel and its subsequent determination were studied and optimized, such as type and volume of the...

A method has been developed for the selective solid phase extraction of Pd(II) based on the adsorption of its 5(p-dimethylaminobenzylidene)rhodanine (PDR) complex on silica gel-polyethylene glycol (Silica-PEG) as a new synthesized adsorbent. The adsorbed complex was eluted using hydrochloric acid—acetone mixture and the concentration of Pd(II) was determined using flame atomic absorption spectr...

An analytical method involving anion exchange high performance liquid chromatographic determination of vitellogenin (Vtg) in fish plasma after postcolumn fluorescence derivatization with o-phthalaldehyde (OPA) was developed. The retention time of Vtg was about 11 min. The reagent variables for derivatization were optimized. The fluorophore was excited at 335 nm and detected at 435 nm. A calibra...