The chromatographic behavior of some flavonoids was established by RP-HPLC on RP-18 (LiChroCART, LiChrosphere RP-18e), RP-8 (Zorbax, Eclipse XDB-C8), CN (S
ulentechnik, LiChrosphere CN100) columns. The mobile phases were mixtures of methanol- water in different volume proportions from 70 to 80% v/v for RP-18 and RP-8, while for the CN column the proportions were between 66 and 70% v/v. The lipophilicity was expressed through different lipophilicity

A study of quantitative analysis of some flavonoids in Satureja hortensis L. extracts is presented. The HPTLC analyses were performed in a normal chromatographic chamber on silica gel plates, with an appropriate mobile phase. Photodensitometric evaluation of the chromatographic plates was performed by UV–visible absorbance at 320 nm for rosmarinic acid and 349 nm for luteoline, after pulverizing with NTS reagent (diphenylboryloxyethylamine). Quantitative

Estrogens have been shown to be present in the water compartment, mainly due to the inefficient removal in wastewater treatment plants (WWTP). The concentrations of these compounds, although very low (low ng/L), are sufficient to induce estrogenic responses and alter the normal reproduction and development of wildlife organisms. The compounds have been determined, by a variety of analytical procedures, in the influents and effluents of WWTP, fresh

Lipophilicity indices for vitamins A and E, and for some precursors of vitamin A, have been determined for the first time by reversed-phase high-performance liquid chromatography (RPHPLC) on C18 and C8 columns. For each column the mobile phases were methanol–water mixtures with methanol in volume proportions from 86 to 90% (v/v) in 1% steps. The regression correlation coefficients obtained for both stationary phases were excellent (usually >0.999).

Rapid separation of 18 synthetic preservatives on the silica gel chemically modified HPTLC plates (RP-18F254s, RP-18wF254s, CN F254s and Nano-SIL Diol/UV254) has been achieved with methanol-water as mobile phase. The development distance was 8 cm in all cases. Identification of the separated preservatives was performed by UV light at l=254 nm. Potassium sorbate, sodium benzoate and ascorbic acid were identified in some soft drinks after sample preparation

A simple and reliable thin layer chromatography (TLC) method for simultaneous separation of some carotenoids (β-carotene, lycopene, lutein, astaxanthin and zeaxanthin), retinoids (retinol, retinoic acid, 9-cisretinal and all-trans-retinal) and tocopherols (α-tocopherol, γ-tocopherol and δ-tocopherol) was described. For a proper separation of all compounds three different mobile phases (Benzene: Petroleum Ether, 10:90, v/v; Methanol: Benzene: