Effects of Autoclaving and Freeze-Drying on Physicochemical Properties of Plectranthus esculentus Starch Derivatives

Autor: Ruth E, Guktur, Elijah I, Nep, Chinwe U, Kemas, Patrick O, Olorunfemi, Ndidi C, Ngwuluka, Nelson A, Ochekpe, Atiene S, Sagay
Rok vydání: 2021
Předmět:
Zdroj: AAPS PharmSciTech. 23(6)
ISSN: 1530-9932
Popis: The goal of this research was to assess the effects of autoclaving followed by freeze-drying on acetylated xerogel (AXS) and carboxymethylated (CMS) derivatives of Plectranthus esculentus starch as potential vaccine stabilizers. Starch extracted from tubers of P. esculentus were modified by single (carboxymethylation) and dual (acetylation followed by xerogel formation) methods. The derivatives were formulated into vaccine stabilizer suspensions, autoclaved, and freeze-dried without additives or antigen. The derivatives and freeze-dried products were assessed by physical appearance, titration, moisture content (MC), TGA, DSC, XRD, SEM, and FTIR analyses. The degrees of substitution (DS) of the CMS and AXS derivatives were 0.345 and 0.033, respectively. Modification significantly reduced the MC of the derivatives. Freeze-dried AXS (FAXS) had lower MC than freeze-dried CMS (FCMS). The lower degree of hydrophilicity/MC of AXS and FAXS was confirmed by TGA and FTIR band intensities and shifts. Reduction in DSC water desorption/evaporation enthalpies (ΔH) from - 1168.8 mJ (NaS) to - 407.48 mJ (AXS) confirmed the influence of modification on moisture. FTIR confirmed acetylation and carboxymethylation of the derivatives by the presence of 1702.9 cm
Databáze: OpenAIRE