Characterisation of a novel, multifunctional, co-processed excipient and its effect on release profile of paracetamol from tablets prepared by direct compression

Objective: To characterise a novel multifunctional pharmaceutical excipient and investigate its effect on paracetamol release from tablets prepared by direct compression. Methods: The excipient was prepared by co-processing gelatinized maize starch with sodium carboxymethyl cellulose and microcrystalline cellulose in a ratio of 2:1:1, dried and pulverized into powder. The excipient formulated was characterized using Fourier transform infrared spectroscopy and differential scanning calorimetry. The excipient was used to prepare batches of tablets by direct compression with drug-excipient ratios of 1:1, 1:2, 1:3 and 1:4. Parameters evaluated on tablets include crushing strength, friability and in vitro dissolution studies. Results: Differential scanning calorimetry analysis revealed a crystalline excipient while Fourier transform infrared spectroscopy showed no interaction between the excipient and paracetamol. Tablets from all the batches gave average crushing strength values between 3.47 and 4.88 kp. The 1:1 and 1:2 tablet batches were comparable to each other while 1:3 and 1:4 were also comparable to one another in their dissolution profiles. The dissolution parameters of the 1:4 batch was faster with – m∞ (90.5%), t50% (3.5 min), t70% (11.6 min) while that of ratio 1:1 was the least with – m∞ (48.6%), m5min (23.8%). Their release kinetics followed a Korsmeyer–Peppas model with a super case-II transport mechanism. Conclusions: The drug-excipient ratios of 1:3 and 1:4 gave pharmaceutically acceptable tablets that met the British Pharmacopoeia specifications. The t50% value of the 1:4 batch of tablets may find its usefulness in formulating drugs for which a fast onset of action is desired