FORMULATION AND EVALUATION OF A 2-COMPONENT COMPOSITE EXCIPIENT “MICROCRYSTARLAC” AS A FILLER-BINDER FOR DIRECT COMPRESSION

A 2-component composite filler- binder was designed and evaluated for direct compression properties. Tapioca starch NTS was modified physically at molecular level by annealing and enzyme hydrolyzed to obtain microcrystalline tapioca starch MCTS which was coprocessed with -lactose monohydrate LMH to form Microcrystarlac MSL. NTS was extracted from cassava tuber Mannihot esculenta crantz using a standard method. The powder suspensions were prepared in concentration of 40 ww in five separate conical flasks. The starch granules were annealed for 1 h and subsequently hydrolyzed with -amylase at 58o and pH 7 for 1 2 3 4 and 5 h in a water bath. The reaction was terminated and neutralized with 0.1 N HCL and 0.1 N NaOH respectively. The MCTS was washed recovered by sedimentation and air dried at room temperature for 72 h. Following characterization the granules that were modified for 3 h sieved fraction 75-250 m was coprocessed with - lactose monohydrate -LMH at concentrations of 10 to 50 ww as a dried mass relative to MCTS. Granule size ranges 75 - 250 m and 90 - 250 m were characterized and compacted at a range of compression load 2.5 to 12.5 KN.Average flow rate angle of repose and compressibility index were 3 gs 32o 22 respectively for MSL granule size range 90 - 250 m and component ratio 5050. The corresponding values for the direct physical mixture of MCTS and lactose are 0.65 gs 40o 53 respectively. MSL shows improved functionality over direct physical mixture of the primary excipients. MSL was compared with Starlac Cellactose and MCC. The onset of plastic deformation Py yield value are Cellactose 24.2 MNm-2MCC 25 MNm-2 MSL 68 MNm-2Starlac 143 MNm-2. The degree of plastic deformation occurring during compression Pk is in the following order MSL 16.4 MNm-2Starlac17 MNm-2MCC 18.6 MNm-2Cellactose 19.1 MNm-2. MSL is more superior in functionality than Starlac Cellactose and MCC. The dilution potential obtained for MSL when compacted with paracetamol PCM and ascorbic acid AA as active drug API were 45 ww PCM with MSL 30 ww AA with MSL. The hardness of MSL containing 45 ww PCM was 80 N. MSL can be employed to formulate harder tablet especially poorly soluble and poorly compressible API.Key words Microcrystarlac Coprocessed Direct compression Filler-binder Microcrystalline Tapioca Starch.