Preparation and release and pharmacokinetics of sustained-release isoniazid / 中国药学杂志

ABSTRACT

To prepare and study the pharmacokinetics and release bioavailability in olunteers and concentrations in plasma in patients. METHODS: Ethylcellulose was used matrix in phase separation-coacervation for preparation of microencapsulation. The release experiments were performed in a rotating shaker. The isoniazid concentration in plasma was determined by spectrophotometrical method following a single oral dose of sustained-release cupsule and ordinary tablet respectively given to 10 volunteers in a open randomized cross-over test. MCP86 was used to process main pharmacokinetic parameters. RESULTS: The sustained-release of capsule and ordinary teblet in vitro, T50 was 1 h and 0.032 h respectively. The drug in sustained-release capsule was sustained release over 10 h. The main parameters in body ordinary tablets cmax=11.12 μgml-1, tmax=1.41 h, K=0.201 h-1; sustained release capsule cmax=4.99 μgml-1, tmax=1.80 h, K=0.03 h-1. The concentration of blood at 36 h was (0±0)μgml-1 and 1.63 μgml-1 respectively. Except tmax, there was significant difference between the two fomulations (P＜0.01). The concentration of blood in patient at 1.5 h and 36 h. ordinary tablet and sustained-release capsule respectively were (8.24±2.60)μgml-1, (0±0)μgml-1and (3.69±0.86)μgml-1, (2.09±0.56)μgml-1. CONCLUSION: The sustained-release capsule will play an important part in prevention and treatment of tuberculosis as the result of its reasonable formulation and simple technology.