The effect of ionotropic gelation residence time on alginate cross-linking and properties

Mitulkumar A Patel; Mohamed H H AbouGhaly; Jacqueline V Schryer-Praga; Keith Chadwick

doi:10.1016/j.carbpol.2016.08.095

The effect of ionotropic gelation residence time on alginate cross-linking and properties

Carbohydr Polym. 2017 Jan 2:155:362-371. doi: 10.1016/j.carbpol.2016.08.095. Epub 2016 Aug 29.

Authors

Mitulkumar A Patel¹, Mohamed H H AbouGhaly², Jacqueline V Schryer-Praga¹, Keith Chadwick³

Affiliations

¹ Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, IN, United States.
² Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, IN, United States; Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Cairo, Egypt.
³ Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, IN, United States. Electronic address: chadwick@purdue.edu.

PMID: 27702523
DOI: 10.1016/j.carbpol.2016.08.095

Abstract

The ability to engineer biocompatible polymers with controllable properties is highly desirable. One such approach is to cross-link carbohydrate polymers using ionotropic gelation (IG). Previous studies have investigated the effect of curing time on alginate cross-linking. Herein, we discuss a novel study detailing the effect of IG residence time (IGRT) on the cross-linking of alginate with calcium ions (Ca²⁺) along with water migration (syneresis) and their subsequent impact on the pharmaceutical properties of alginate particles. IGRT was shown to have a significant effect on particle size, porosity, density, mechanical strength and swelling of calcium alginate particles as well as drug release mechanism. Furthermore, we describe a novel application of electron dispersive spectroscopy (EDS), in conjunction with Fourier Transform- infra red (FT-IR) spectroscopy, to analyze and monitor the changes in Ca²⁺ concentration during cross-linking. A simple procedure to determine the concentration and distribution of the surface and internal Ca²⁺ involved in alginate cross-linking was successfully developed.

Keywords: Attenuated total reflectance-Fourier transform IR; Calcium alginate; Electron dispersive spectroscopy; Ionotropic gelation residence time; Polymer cross-linking.