DRUG RELEASE AND COMPRESSING PROPERTIES OF SUSTAINED RELEASE MATRIX TABLETS WITH NEWLY DESIGNED HYDROPHILIC FUNCTIONAL POLYMER PARTICLES BY A SPRAY-DRYING TECHNIQUE

摘要

Two types of novel functional particles containing hydrophilic polymers were prepared by using a spray-drying technique for improving the drug release properties of the resultant sustained released matrix tablets and their micromeritic properties. Surface modification of hydroxypropylmethylcellulose (HPMC) particles with tannic acid or Eudragits were found to lead to retardation of drug release of the resultant matrix tablets. The decrease in erosion rate of the tablets was responsible for the prolonged drug release. The drug release rate could be controlled by the amount and type of polymers formulated into the particles. Co-spray-drying of sodium alginate with lactose in a solution produced composite particles having improved micromeritic and drug release properties. The compressing properties of particles were found to be much improved compared with commercial lactose particles and a physically mixed individual particles. Dry coated tablets with the composite particles showed a controlled drug release pattern, in which a long induction period preceded a following rapid drug release. Additional formulation of a small amount of chitosan to the spray-dried particles could considerably prolong the induction period.