Comparative physicochemical and release properties of amoxicillin trihydrate tablet formulated with different binders

Abstract

This research evaluated and compared the physicochemical and release properties of amoxicillin trihydrate tablet, formulated with different types and concentrations of binders - Pectin powder BP (PTN), Microcrystalline cellulose BP (MCC) and Polyvinyl-pyrrolidone BP (PVP) at 5, 7.5, 10 and 12.5 %w/w respectively. Direct compression method was used to prepare the amoxicillin trihydrate tablet. The micromeritics of the mixed powder evaluated were: flow rate, angle of repose, bulk and tapped densities, Hausner’s ratio and Carr’s index. The amoxicillin mixed powder was compressed into tablets using Single Punch Manesty tableting machine at 30 N/m². The physicochemical properties of the amoxicillin tablet evaluated were moisture absorption test, hardness, weight uniformity, friability, disintegration time and dissolution profiles. Results were as follows: flow rate (g/sec): 2.50 – 2.82 (PVP), 1.40 – 2.15 (PTN), and 1.50 – 2.75 (MCC); angle of repose: 26.6⁰ – 29.2⁰ (PVP), 26.2⁰ – 36.5⁰ (PTN), and 29.2⁰ -34.4⁰ (MCC); bulk density (g/cm³): 0.53 - 0.60 (PVP), 0.53 - 0.61 (PTN), and 0.59 - 0.64 (MCC); tapped density (g/cm³): 0.63 - 0.68 (PVP), 0.58- 0.68 (PTN) and 0.63 – 0.72 (MCC); Hausner’s ratio: 1.13 – 1.26 (PVP), 1.04 – 1.16 (PTN) and 1.06 – 1.13 (MCC); Carr’s index (%): 11.76 – 20.89 (PVP), 3.44 – 11.86 (PTN) and 5.97 – 11.11 (MCC). Results of the physicochemical tests showed tablet hardness (kg): 5.00 – 7.20 (PVP), 4.90 – 7.30 (PTN) and 4.58 – 7.50 (MCC); friability (%): 0.85 - 1.12 (PVP), 0.75 – 1.00 (PTN), 0.72 – 0.90 (MCC); mean weight (mg): 0.57 – 0.58 (PVP), 0.57 – 0.58 (PTN) and 0.57 – 0.58 (MCC); tensile strength (Nm_-2): 5.36 – 7.46 (PVP), 5.00 - 7.55 (PTN), and 4.81 – 7.75 (MCC); disintegration time (min): 3.20 – 6.40 (PVP), 3.70 – 6.50 (PTN) and 3.40 – 5.80 (MCC). The dissolution profile showed increase in the percentage amount of drug released with time, but a decrease in the amount released with increase in binder concentration. At 5% w/v binder concentration and at 45 min, the drug releases were: 70% (PVP), 65% (PTN), and 68% (MCC). The study revealed that all the binders were appropriate in the formulation of amoxicillin trihydrate tablets and at higher concentrations they could be used to formulate a sustained release dosage form of the drug.