Determination of sildenafil by various methods and in various media is reviewed in this paper. The methods used consist of ultraviolet (UV) spectroscopy, thin layer chromatography (TLC), and high-performance liquid chromatography (HPLC). These methods were used to determine the amount of sildenafil in pharmaceutical preparations, soft drinks, and biological liquids. HPLC was used for evaluation...

Strawberry is rich in anthocyanins, which are responsible for the red color, and contains several colorless phenolic compounds. Among the colorless phenolic compounds, some, such as hydroxycinammic acid derivatives, emit blue-green fluorescence when excited with ultraviolet (UV) light. Here, we investigated the effectiveness of image analyses for estimating the levels of anthocyanins and UV-exc...

In this study, a high-performance liquid chromatographic method (HPLC) and UV spectrophotometric method were developed, validated and applied for the determination of theophylline in biological fluids. Liquid- liquid extraction is performed for isolation of the drug and elimination of plasma and saliva interferences. Urine samples were applied without any extraction. The chromatographic separat...

Hypertension caused by angiotensin II is characterized by an increase in tissue oxidant stress as evidenced by increased quantities of reactive oxygen and nitrogen species. Manganese superoxide dismutase (MnSOD) is a key mitochondrial antioxidant enzyme that is inactivated in conditions of oxidant stress by reacting with peroxynitrite to form 3-nitrotyrosine in its active site. The increase in ...

Simple and sensitive methods using high-performance liquid chromatography-diode array detection (HPLC-DAD) and ultraviolet (UV)-spectrophotometry were developed and compared to quantify lychnopholide (LYC) in poly-ε-caprolactone nanocapsules and to study its release kinetics. Both methods were validated concerning their specificity, linearity, limits of detection and quantification, precision, ...

In this study, a high-performance liquid chromatographic method (HPLC) and UV spectrophotometric method were developed, validated and applied for the determination of theophylline in biological fluids. Liquid- liquid extraction is performed for isolation of the drug and elimination of plasma and saliva interferences. Urine samples were applied without any extraction. The chromatographic separat...

A high-performance liquid chromatography (HPLC) method for normal and formaldehyde-modified deoxynucleosides after hydrolysis of exposed and unexposed human placental DNA was compared with ultraviolet (UV), fluorescence (FL), and electrochemical (EC) detectors. The lower quantifiable limits (LQL) for UV detection at 254 nm were 10-22 pmol for N(6)-hydroxymethyldeoxyadenosine (N(6)-dA), N(2)-hyd...

high-performance liquid chromatography (hplc) methods employing ultraviolet (uv) detector are not sufficiently sensitive to measure the low plasma concentrations following single oral dose of imipramine. therefore, in the present study a simple, rapid and yet sensitive hplc method with uv detection was developed and validated for quantitation of imipramine in human plasma samples. an efficient ...

An unknown vitamin D compound was observed in the HPLC-UV chromatogram of edible mushrooms in the course of analyzing vitamin D(2) as part of a food composition study and confirmed by liquid chromatography-mass spectrometry to be vitamin D(4) (22-dihydroergocalciferol). Vitamin D(4) was quantified by HPLC with UV detection, with vitamin [(3)H] itamin D(3) as an internal standard. White button, ...

Extracts of Phanerochaete chrysosporium cultures grown on birch or on a malt extract-peptone-glucose agar medium were analysed by HPLC. A major component from the two sources appears to be identical by HPLC and UV-visible spectrometry. The product isolated from agar-grown cultures was purified to apparent homogeneity and structure analysis by NMR indicates that the metabolite is the beta-resorc...