IMPROVEMENT OF THE PHYSICOCHEMICAL PROPERTIES OF AMOXICILLIN TRIHYDRATE POWDER BY RECRYSTALLIZATION AT DIFFERENT pH VALUES

摘要

The.purpose.of.this.research.was.to.investigate.and.improve.some.physicochemical.and.solid‐state.properties.of.amoxicillin.trihydrate..This.raw.material.was.obtained.from.different.suppliers.and.differed.in.both.particle.size.distribution.and.crystal.shape...The.particle.size..and.crystal.shape.were.determined.using.eight.sieves.and.a.scanning.fluorescence.microscope,.respectively..The.drug.was.filled.in.hard. gelatin. capsules. as. a. single. dose. of. 250. mg.. Drug. dissolution. was. evaluated. using. dissolution. tester.. Samples. were. analyzed. using. U.V.spectrophotometer.at.a.wavelength.272nm..The.results.indicated.that.the.dissolution.rates.of.amoxicillin.trihydrate.are.affected.by.both.the.crystal.shape.and.the.particle.size..To.improve.the.dissolution.rate.of.amoxicillin.trihydrate.,.it.was.recrystallized..from.aqueous.solutions.at.different.pH.values.(2,.4,.7,.9.and.11)..Amoxicillin.trihydrate.samples. recrystallized.from. aqueous. solu tions.at.pH7.and.pH9.appear.to.have.superior.physicochemical.properties. to.the.original.amoxicillin.trihydrate.samples...The.pH.of.crystallization.medium.had.a.significant.effect.on.the.dissolution.rate.of.amoxicillin.trihydrate.powder...Samples.recrystallized.at.pH.11.and.pH9.showed.higher.dissolution.rates.compared.to.samples.recrystallized.at.pH.2,.pH4.,.pH7.and.the.original.amoxicillin.trihydrate.samples.but.the.flowability.of.the.powder.recrystallized.at.pH.11.was.very.poor.compared.to.other.samples