In this study, electrochemical molecularly imprinted sensors were fabricated and used for the determination of ascorbic acid (AA). Nanofiber membranes of cellulose acetate (CA)/multi-walled carbon nanotubes (MWCNTs)/polyvinylpyrrolidone (PVP) (CA/MWCNTs/PVP) were prepared by electrospinning technique. After being transferred to a glass carbon electrode (GC), the nanofiber interface was further ...

The use of beta-blockers to enhance performance in some sports is forbidden. Based on this regulation, there is a demand for dynamic analytical procedures for analyzing these compounds quickly and without manual sample preparation. Therefore, the use of a molecularly imprinted polymer (MIP) in a multidimensional liquid chromatographic system coupled to a mass spectrometer provides a good altern...

With the aim of preparing the 16 possible ribodinucleotides derived from the four principal ribonucleotides, we made a kinetic study to determine the optimum conditions for a partial alkaline hydrolysis of RNA. Satisfactory results were obtained when the hydrolysis of RNA (1g.) in 0.2m-sodium hydroxide (100ml.) at 37 degrees was ceased approx. 10min. after the start of the reaction. The relativ...

A biotinylated nucleotide analog containing a disulfide bond in the 12-atom linker joining biotin to the C-5 of the pyrimidine ring has been synthesized. This analog, Bio-SS-dUTP, is an efficient substrate for Escherichia coli DNA polymerase I. Bio-SS-dUTP supported DNA synthesis in a standard nick-translation reaction at 35%-40% the rate of an equal concentration of the normal nucleotide, TTP....

The degree of conversion (DC) and the released bisphenol A diglycidyl ether dimethacrylate (BisGMA), triethylene glycol dimethacrylate (TEGDMA) and urethane dimethacrylate (UDMA) monomers of bulk-fill composites compared to that of conventional flowable ones were assessed using micro-Raman spectroscopy and high performance liquid chromatography (HPLC). Four millimeter-thick samples were prepare...

An enolase has been purified to apparent homogeneity, as measured by gel electrophoresis, some 400-fold from spinach (Spinacia oleracea). This is the first plant enolase that has been purified to homogeneity. At moderate ionic strengths, the 5,5-dithio-bis-2-(nitrobenzoate) (DTNB)-or parachloromercuribenzoate-reacted enzyme elutes from a Bio-Gel P-200 column with somewhat greater volumes than t...

Ion exchange is a very useful technique to separate protein mixtures under mild conditions, most commonly by applying a shallow gradient of increasing salt concentration as eluent. pH gradient elution is used much less frequently, except in specialist applications such as chromatofocusing, and can require complex buffer systems. However, today’s modern quaternary HPLC systems are ideally suited...

Even though antibiotic eluting bone cements are successfully used in orthopedic practice, adding chemotherapy drugs to bone cement pose a different set of problems. This is mainly due to the toxicity concerns associated with the use of chemotherapy agents. To avoid local or systemic toxicity, the drug elution profile of a particular bone cement/drug concentration need to be determined. The drug...

A modified broth-disk elution method for routine susceptibility testing of anaerobic bacteria was compared with the proposed reference agar dilution method under study by the National Committee on Clinical Laboratory Standards. The broth-disk elution method used a 24-h test incubation period, Schaedler broth medium supplemented with menadione, and GasPak (BBL Microbiology Systems) incubation. R...