A high-performance liquid chromatography:chemiluminescence method for potential determination of vardenafil in dietary supplement.

A flow method of high-performance liquid chromatography (HPLC) seperation and chemiluminescence (CL) detection for sensitive vardenafil analysis in dietary supplements was developed. The vardenafil separation was achieved on a C18 column at 30°C using ethanol-H(3)PO(4) and ethylenediaminetetraacetic acid disodium salt (Na(2)EDTA) aqueous solution (25 : 75, v/v%) as mobile phase. The followed continuous CL detection was conducted based on the strong CL enhancement by the presence of vardenafil to luminol-K(3)Fe(CN)(6) reaction in alkaline medium.

Three-dimensional positron emission tomography/computed tomography analysis of 13NO3- uptake and 13N distribution in growing kohlrabi.

We report the application of three-dimensional positron emission tomography/computed tomography (PET/CT) for the analysis of (13)NO(3)(-) uptake and (13)N distribution in growing kohlrabi. The analytical procedures, equipment parameters, and image reconstruction mode for plant imaging were tested and selected. (13)N in growing kohlrabi plants was imaged versus time using both PET movies and PET/CT tomograms.

Utilizing multibubble sonophotoluminscence for calcium quantitative analysis in pharmaceuticals.

Sonoluminescence can photoexcite fluorescent solutes yielding sonophotoluminescence (SPL). The possibility of applying multibubble sonophotoluminescence (MBSPL) for chemical quantitative analysis is examined in this work. Special devices for MBSPL quantitative detection are designed and fabricated.