Determination of Plasma Protein Binding Rate of Bencycloquidium Bromide

The plasma protein binding rate of bencycloquidium bromide of rats and human were determined.After addition of internal standard, the plasma samples were deproteinized with methanol, and the supernatant was assayed by LC/ESI/MS.Equilibrium dialysis was employed to determine the plasma protein binding rate of bencycloquidium bromide in rats and human.The plasma protein binding rate of bencycloquidium bromide with rats and human plasma were 42.0% and 71.4%,respectively.The ranges of plasma concentration of bencycloquidium bromide were 105.2 to 1842 ng/ml for rats and 305.3 to 3813 ng/ml for human,respectively,in which the plasma protein binding was linear.The plasma protein binding rate of bencycloquidium bromide in various species was different.The plasma protein binding rate of bencycloquidium bromide in human was greater than in rats and the binding rate of bencycloquidium bromide with human plasma protein was middling strength.