ABSTRACT
Comparative pharmacokinetics of anti-influenza drug composition Antigrippin-maximum administered in capsules and a powder for preparing solutions has been studied after single administraton in a group of 18 healthy volunteers. Both preparations [manufactured by the Antiviral Research and Production Corporation (St Petersbutg) contain 6 active components, including paracetamol, rimantadine, loratadine, ascorbic acid, calcium gluconate, and rutoside in equal amounts. The concentrations of unchanged paracetamol, rimantadine, and loratadine in the blood plasma were degtermined by HPLC with mass-spectrometric and UV detection. The pharmacokinetic parameters of allindicated active components exhibited no detectable distinctions, except for the time to attaining maximum concentration ofparacetamol and the value of the maximum concentration of loratadine.
Subject(s)
Acetaminophen/pharmacokinetics , Antiviral Agents/pharmacokinetics , Capsules/chemistry , Loratadine/pharmacokinetics , Powders/chemistry , Rimantadine/pharmacokinetics , Acetaminophen/administration & dosage , Acetaminophen/blood , Adult , Antiviral Agents/administration & dosage , Antiviral Agents/blood , Area Under Curve , Biological Availability , Chromatography, High Pressure Liquid , Drug Combinations , Female , Half-Life , Humans , Influenza, Human/drug therapy , Influenza, Human/virology , Loratadine/administration & dosage , Loratadine/blood , Male , Mass Spectrometry , Orthomyxoviridae/drug effects , Rimantadine/administration & dosage , Rimantadine/blood , Russia , Solutions/chemistryABSTRACT
Penicillin acylase substrates suitable for colorimetric determination of the enzyme activity have been tested in this study. The kinetic parameters (Km and kcat) have been elucidated for the following nine substrates: six phenylacetic acid derivatives (p-nitroanilide, p-nitrophenyl ester, p-nitro-m-carboxyanilide, p-nitro-o-carboxyanilide, p-nitro-o-hydroxyanilide, m-nitro-p-carboxyanilide), two D-phenylglycine derivatives (p-nitroanilide, p-nitro-m-carboxyanilide), and also p-nitrophenyl ester of acetic acid (p-nitrophenyl acetate). With the exception of p-nitrophenyl acetate, all the compounds studied are highly specific chromogenic substrates for penicillin acylase, but their reactivity is very variable and kcat/Km values are in a range from 0.8.10(4) to 5.10(6) M(-1).sec(-1).
