A rapid and simple method of utilizing thin-layer chromatography (TLC) and pyrolysis gas chromatography (PyGC) for the identification and determination of methylbenactyzium bromide in human urine was studied in this report. Methylbenactyzium bromide was extracted from urine with ODS-cartridge (Sep-Pak C18), then spotted onto a silica gel 60 F254 TLC plate. After development, the separated spot ...

An analytical method using pentafluorobenzyl bromide (PFBB) derivatization and gas chromatography/mass spectrometry (GC/MS) has been applied to identify and quantify chloro-, bromo- and dichlorophenols in air, water and sediment samples. Phenols in air sample were collected with a PS-2 Sep-PAK cartridge, and eluted with 2-propanol. For water and sediment samples, liquid-liquid extraction with d...

A high-performance liquid chromatography method coupled with electrospray ionization-mass spectrometry for the determination of polyphenols in tobacco is studied. The polyphenols are extracted from a tobacco sample by being refluxed in a boiling water bath with 80% methanol and purified by solid-phase extraction with a C18 cartridge. The chlorogenic acid, rutin, scopoletin, caffeic acid, scopol...

Insulin is readily concentrated from 10 to 50 ml of urine with better than 75% recovery using octadecylsilyl (ODS) silica columns (C18Sep-Pak cartridge) and can then be measured by radioimmunoassay. Fractionation on Sephadex G50 gel filtration reveals that the apparent immunoreactivity corresponds for the most part to 6000 dalton insulin. Renal clearance of insulin in 5 normal subjects does not...

We previously developed an HPLC method for determination of lanatoside C, digoxin and α-acetyldigoxin in digitalis glycosides isolated from Digitalis lanata leaves. Here, we present an improved HPLC-UV method to determine those compounds and deslanoside. We used the improved method to examine the effects of various pretreatments on the amounts of the four compounds isolated from the leaves, wit...

A simple and selective high-performance liquid chromatographic (HPLC) method has been developed for determination of ciprofloxacin in human gingival crevicular fluid (GCF). GCF samples were collected with paper strips. Ciprofloxacin was extracted from the pooled strips with methanol–water, 50:50 (v/v), and separated on a cartridge column (Radial-pak C18, 100 mm × 8 mm, 10 μm) with acetonitrile–...

A simple and reliable method using liquid chromatography-electrospray ionization-mass spectrometry (LC/ESI-MS) has been developed for the determination of the macrolide antibiotics spiramycin and tilmicosin in meat and fish. The drugs were extracted from meat and fish with 0.2% metaphosphoric acid-methanol (6:4), and the extracts were cleaned up on an Oasis HLB cartridge (60 mg). Positive ioniz...

Isolated rat hindlegs were perfused with Krebs-Ringer solution, and immunoreactive angiotensin II (irAng II) released into the perfusate was directly determined using a Sep-Pak C18 cartridge connected to the perfusion system. High performance liquid chromatography clearly demonstrated the presence of angiotensin I (Ang I), angiotensin II (Ang II), and a small amount of angiotensin III. The spon...

IAA in plant tissues has been analyzed by a number of physico-chernical methods. GC-MS has been used for both qualitative and quantitative analyses with deuterium-labeled IAA as the internal standard (Caruso et al. 1978, Magnus et al. 1980, Pengelly et al. 1981). This GC-MS method however, requires extensive purification of the plant extract and additional procedures for the preparation of vola...

Adenosine may be a physiological modulator of vascular smooth muscle tone, sympathetic neurotransmission, renin release, and renal and cardiac function. To facilitate the elucidation of the physiological role of adenosine, a microassay for adenosine was developed that allows accurate quantitation of adenosine in 75 microliters of rat plasma, thus permitting multiple determinations of plasma ade...