Chemometrics optimized microencapsulation of ergocalciferol using emulsification technique and its physico-chemical characterization

Abstract

The study reports the microencapsulation of ergocalciferol (vitamin D2) by emulsification technique, the experimental process parameters being chemometrically optimized by d-optimal mixture design approach followed by physico-chemical characterization of the resultant emulsion. Basing on desirability ramp function graph and lab experimentation results, the percentages of Ca stearate (0.124), Ca carbonate (0.385), Ethanol (5.0), Tween 80 (4.16), Span 80 (0.25) showed a maximum of 94.1% encapsulation efficiency. The optimized ergocalciferol emulsion showed particle size in the range of 469–493 nm, polydispersity index 0.23–0.24, zeta potential (ζ) value ranging from -15.27 to -15.35 mv; viscosity and interfacial tension was determined to be 1.401±0.02 mPaS and 23.1 mNm−1 respectively. The resultant emulsion showed no visual change in physical appearance, consistency, and color on keeping undisturbed for 7 days. Results of accelerated stability studies have shown that the initial ergocalciferol or (vitamin D2) content (83.75±0.03%) in the emulsion after storage at (55 °C, 75% RH) was found to be 83.05±0.01% and after storage at (75 °C, 80% RH) is 82.91±0.05%. From the results of accelerated stability studies it can be concluded that vitamin D2 emulsion is comparatively stable at high temperature storage conditions (75 °C, 80% RH). The devised optimized procedure of microencapsulation by emulsification of ergocalciferol was found to be effective with high encapsulation efficiency and significant stability of the emulsion system.