A radioimmunoassay for physostigmine in biological fluids and tissues

The Pharmacology of Physostigmine

“…Physostigmine and physostigmine metabolite (Fig. 1) concentrations can be measured by HPLC (42,141,148,176,177,230,280) and by radioimmune assay (176,177). From these studies, it has been determined that physostigmine has a high clearance, is eliminated almost entirely via metabolic pathways, and has a high hepatic extraction ratio.…”

Biologically active components of Physostigma venenosum

“…A similar approach, with slightly higher sensitivity, was described by Miller and Verma [30]. In their method, antibodies were produced in rabbits immunized with physostigmine conjugated to bovine serum albumin (BSA) by two different methods: a diazo immunogen coupled to BSA with carbodiimide and a Mannich coupled immunogen.…”

“…PK studies with physostigmine have been conducted in several animal species including rat [22][23][24][25][26], guinea pig [27] and dog [28]. Physostigmine and/or its metabolite concentrations can be measured by HPLC [22,23] and by radioimmune assay [29,30]. These studies show that physostigmine has a high clearance and hepatic extraction ratio; and is eliminated almost entirely via several metabolic pathways.…”

“…The specificity of the RIA was further validated by measuring physostigmine concentrations in biological samples in tandem with high-pressure liquid chromatography. The RIA was used to study the time course of plasma concentrations and tissue distribution of physostigmine in rats [30].…”

Analysis of acetylcholinesterase inhibitors: bioanalysis, degradation and metabolism

“…Miller and Verma developed a radioimmunoassay to study the time course of plasma concentrations and tissue distributions of 1 in rats (Miller and Verma, 1989).…”