ABSTRACT
The use of starches as natural polymers for
pharmaceutical applications remains attractive because
they are cheap, readily available, biodegradable and
capable of modification (Lawal et al., 2007; Yiu et al.,
2008; Okunlola et al., 2010). Native starch is a white
powder with a bland taste and flavor, and is insoluble in
cold water. Due to the sub-optimal properties of native
starches, modifications are efficient methods of improving
their suitability as excipients for specific pharmaceutical
uses. Physical modification entails subjecting the
starch to heat-moisture treatment and annealing, while
chemical modification includes oxidation, acid thinning,
hydroxypropylation and acetylation. Starches have been
chemically modified by acid hydrolysis for over 150
years (Yiu et al., 2008). This process involves suspending
starch in an aqueous solution of hydrochloric acid or
sulphuric acid at certain temperatures. In the presence of
strong acid and heat, the glycosidic bonds between the
monosaccharides in the starch polymer are cleaved (Yiu et
al., 2008). Acid modification has been shown to change the
physicochemical properties of starch without destroying
its granular structure, yielding starch with increased
solubility and gel strength but decreased viscosity; the
extent of hydrolysis depends on starch consistency, the
acidity of the medium, the hydrolysis temperature and the
duraton of hydrolysis (Odeku et al., 2009).
Okunlola, A (2021). Characterization and evaluation of acid-modified starch of Dioscorea oppositifolia (Chinese yam) as a binder in chloroquine phosphate tablets. Afribary. Retrieved from https://afribary.com/works/characterization-and-evaluation-of-acid-modified-starch-of-dioscorea-oppositifolia-chinese-yam-as-a-binder-in-chloroquine-phosphate-tablets
Okunlola, Adenike "Characterization and evaluation of acid-modified starch of Dioscorea oppositifolia (Chinese yam) as a binder in chloroquine phosphate tablets" Afribary. Afribary, 22 Apr. 2021, https://afribary.com/works/characterization-and-evaluation-of-acid-modified-starch-of-dioscorea-oppositifolia-chinese-yam-as-a-binder-in-chloroquine-phosphate-tablets. Accessed 21 Nov. 2024.
Okunlola, Adenike . "Characterization and evaluation of acid-modified starch of Dioscorea oppositifolia (Chinese yam) as a binder in chloroquine phosphate tablets". Afribary, Afribary, 22 Apr. 2021. Web. 21 Nov. 2024. < https://afribary.com/works/characterization-and-evaluation-of-acid-modified-starch-of-dioscorea-oppositifolia-chinese-yam-as-a-binder-in-chloroquine-phosphate-tablets >.
Okunlola, Adenike . "Characterization and evaluation of acid-modified starch of Dioscorea oppositifolia (Chinese yam) as a binder in chloroquine phosphate tablets" Afribary (2021). Accessed November 21, 2024. https://afribary.com/works/characterization-and-evaluation-of-acid-modified-starch-of-dioscorea-oppositifolia-chinese-yam-as-a-binder-in-chloroquine-phosphate-tablets