Acetylation and Evaluation of Taro Boloso-I Starch as Directly Compressible Excipient in Tablet Formulation

Abstract

Taro Boloso-I (TB1), a newly improved Colocasia esculenta variety, is a potential source of starch with high yield. However, to improve some limitations of the native starches (NS), such as flowability and compactibility, different physical and chemical starch modifications have been employed. Acetylation is one of the chemical modifications which improves the flow and compaction of the NS, which are prerequisite during direct compression (DC) of tablets. Hence, in this study, TB1 starch was acetylated using acetic anhydride and evaluated as an ideal excipient for direct compression. Starch acetates (SA) with a degree of substitution (DS) of 0.072 (SA1) and 0.695 (SA2) were produced and evaluated. FTIR spectra of the SAs were used to verify the acetylation of the NS. Powder flow evaluation parameters showed significant improvement in the flow properties of the NS following acetylation. In addition, the swelling power, solubility, and compactibility were also improved. Tensile strength (TS) of the tablets comprising SAs only, SA1 (41.40) and SA2 (63.43 Kg/cm2), was significantly higher than tablets made of the NS (31.96) and Starch 1500® (15.12 Kg/cm2). The SAs also showed lower sensitivity towards lubrication than the NS and Starch 1500® as lower lubricant sensitivity ratios were recorded. In addition, tablets comprising the SAs satisfactorily accommodated at least up to 50 % w/w paracetamol—compared to 30 % w/w by Starch 1500®—upon DC processing. The paracetamol tablets comprising SAs also complied with the United States Pharmacopeia specifications for disintegration and dissolution studies. Therefore, taking all the facts into consideration, the SAs could be potential DC excipients in tablet formulations.

Optimization and Characterization of Extruded Partially Pregelatinized Cassava Starch as Filler-Binder

“…Starch 1500 ® can only be measured with a flow time of 9.3 s for 100 g powder (flow rate 10.75 g/s) when the water content has been reduced to less than 5%. This outcome was similar to the findings of Getachew et al (2020) who reported 10.50 g/s in their study. The optimized PPCS has 32.5° angle of repose that has considerably good flow according to European Pharmacopoeia (2010).…”

“…Actual bulk density of the optimized PPCS is close to Starch 1500 ® (0.648 g/mL; 0.621 g/mL in Getachew et al's study (2020)), but the optimized PPCS's tapped density was lower than Starch 1500® (0.920 g/mL). This time, Getachew et al (2020) reported a different tapped density of Starch 1500 ® : 0.726 g/mL, which resulted in a difference in Carr index and Hausner ratio results with the value recorded in this work. Carr index and Hausner ratio of the optimized PPCS were smaller than Starch 1500 ® , which means that the optimized PPCS has better flowability.…”

“…The optimized PPCS has 32.5° angle of repose that has considerably good flow according to European Pharmacopoeia (2010). Starch 1500 ® has surprisingly lower angle of repose that is 28.8° (excellent flowability) and 25.56° as reported from the findings of Getachew et al (2020). Other pregelatinized cassava starch has lower angle of repose than the optimized PPCS.…”

Advances of cassava starch-based composites in novel and conventional drug delivery systems: a state-of-the-art review

“…130 Apart from this, native cassava starches have elevated lubricant sensitivity and poor flowability as well as high cohesiveness, mainly due to small particle size and large surface area, which limit their use in the formulation of direct compaction or compression tablets. 131,132 These are all major constraints of native cassava starch which can be overcome by starch modification, expanding the utilization of cassava starches as an excipient in pharmaceutical dosage forms.…”

Efficacy of Cassava Starch in the Design of Drug Delivery Platforms: From Roots to Polymers

“…In contrast to thermal stability and pasting pro le, the native form of cassava starches showed low thermal transition temperature, which directly provides less structural stability and thermal instability resulting in makes the granule more liable to gelatinization, while native cassava starch exhibited noticeable increases in viscosity followed by considerable paste thinning [108]. Furthermore, native cassava starches have elevated lubricant sensitivity and poor owability as well as high cohesiveness mainly due to small particle size and large surface area, which limited their use in the formulation of direct compaction or compression tablets [109,110]. These all are the major constraints of native cassava starch which reduce its uses in pharmaceutical dosage forms.…”