A Novel Simultaneous Determination of Sarpogrelate and its Active Metabolite (M-1) in Human Plasma, Using Liquid Chromatography-Tandem Mass Spectrometry: Clinical Application.

BACKGROUND: This study describes a novel analytical method for simultaneously determining sarpogrelate and its metabolite (M-1) in human plasma, using liquid chromatography coupled with tandem mass spectrometry, with electrospray ionization in the positive ion mode. METHODS: Sarpogrelate, M-1, and labeled internal standard (d3-sarpogrelate) were extracted from 50 µL of human plasma by simple protein precipitation. Chromatographic separation was performed by using a linear gradient elution of a mobile phase involving water-formic acid (99.9:0.1, v/v) and acetonitrile-formic acid (99.9:0.1, v/v) over 4 min of run time on a column, with a core-shell-type stationary phase (Kinetex C18, 50 mm×2.1 mm i.d., 2.6-µm particle size, Phenomenex, USA). Detection of the column effluent was performed by using a triple-quadruple mass spectrometer in the multiple-reaction monitoring mode. RESULTS: The developed method was validated in human plasma, with lower limits of quantification of 10 ng/mL for sarpogrelate and 2 ng/mL for M-1. The calibration curves of sarpogrelate and M-1 were linear over the concentration ranges of 10-2,000 and 2-400 ng/mL, respectively (R(2)>0.99). The carry-over effect, precision, accuracy, and stability of the method met the criteria for acceptance. CONCLUSIONS: A simple, fast, robust, and reliable analytical method was successfully developed and applied to the high-throughput determination of sarpogrelate and its metabolite in real plasma samples in a pharmacokinetic study of healthy subjects.

Influence of gelatin and bovine serum lubricants on ultra-high molecular weight polyethylene wear debris generated in in vitro simulations.

Ultra-high molecular weight polyethylene (UHMWPE) wear debris induced osteolysis has a major role in the late aseptic loosening and ultimate failure of total hip replacements (THR). Clinically relevant in vitro simulations of wear are essential to predict the osteolytic potential of bearing surfaces in artificial hip joints. Newborn calf or bovine serum has been accepted as a boundary lubricant for such in vitro tests, but its biological stability has been questioned. This study compared the wear factors, number of wear particles and levels of microbial contamination produced in bovine serum and a gelatin-based lubricant. The wear factors produced by the two lubricants were not significantly different, however the wear debris morphology produced was substantially different. The bovine serum became contaminated with micro-organisms within 28 h, whereas the protein-based lubricant remained uncontaminated. The results showed that bovine serum was not a stable boundary lubricant. They also showed that although the wear factors for the two solutions were not significantly different, the protein-based lubricant was not a suitable alternative to bovine serum because the wear debris produced was not clinically relevant.

Nutritional value of succinic acid monoethyl ester in starvation.

Rats were fasted for 48 h, but infused with either NaCl or the sodium salt of monoethyl succinic acid (EMS), both delivered at a rate of 80 mumol/g body weight per day. The infusion of EMS, as compared to NaCl, failed to affect paraovarian adipose tissue or liver weight, liver or muscle glycogen, and insulinemia. It accentuated the starvation-induced fall in body weight, and decreased both liver and muscle protein content. Nevertheless, the succinate ester increased plasma D-glucose concentration, delayed the rise in ketonemia, maintained a higher glucokinase/hexokinase activity ratio in liver and pancreatic islets, and allowed for a more efficient stimulation of insulin release by D-glucose or 2-ketoisocaproate in isolated pancreatic islets. These findings indicate that monoethyl succinate displays a significant nutritional value when infused in starved rats.