the purpose of this study was to investigate the effect of additives, poly(ethylene glycol) (peg) 1450, poloxamer 407, polyvinyl alcohol (pva) and sodium chloride in order to improve physico-chemical characteristics, encapsulation efficiency and in vitro release of bovine serum albumin, form poly(d,l-lactic-co-glycolic acid) (plga) microparticles prepared by the w/o/w solvent evaporation method...

background: the most reliable indicator of vitamin d status is circulating concentration of 25‑hydroxycalciferol (25(oh) d) routinely determined by enzyme‑immunoassays (eia) methods. this study was performed to compare commonly used competitive protein‑binding assays (cpba)‑based eia with the gold standard, high‑pressure liquid chromatography (hplc). methods: concentrations of 25(oh) d in sera ...

Recent advances in single-molecule enzymology are reviewed. The theoretical underpinning of sincle-molecule enzymatic behaviors is discussed and exemplified by experiements and statistical analyses. In particular, the manifestations of the Michaelis-Menten mechanism, the kinetic scheme with sequential intermediates, and dynamic disorder in single molecule data are presented. A survey of current...

In a sequence of coupled enzyme reactions the steady-state production of product is preceded by a lag period or transition time during which the intermediates of the sequence are accumulating. Provided that a steady state is eventually reached, the magnitude of this lag may be calculated, even when the differentiation equations describing the process have no analytical solution. The calculation...