• Mohy Eldin Ms. University of Jeddah
  • Omer Am. Polymer Materials Research Department, Advanced Technology and New Materials Research Institute, City for Scientific Research and Technological Applications, Alexandria, Egypt
  • Wassel Ma. AL-Azhar University
  • Tamer Tm. Advanced Technology and New Materials Research Institute
  • Abd Elmonem Ms. National Organizations for Drug Control and Research
  • Ibrahim Sa. National Organizations for Drug Control and Research


Objectives: Preparation and characterization of a new pH sensitive chitosan (CS) grafted alginate (ALG) hydrogel microcapsules for the oral delivery of protein.

Methods: The pH sensitive hydrogel microcapsules were prepared for the first time using “grafting to†technique. Firstly, alginate was activated using Ï-Benzoquinone (PBQ) as a coupling agent to graft Chitosan chains later on. Both of activated and grafted alginate microcapsules were characterized by Fourier transform-Infra red spectroscopy (FT-IR), thermal gravimetric analysis (TGA) and the morphological structures were investigated using Scanning electron microscopy (SEM) examination.

Results: It was found that the optimum conditions affecting the activation process and also the swelling degree of the prepared hydrogel microcapsules were 2% ALG, 0.04M PBQ pH10, 45 °C for 2h. In addition, the grafting process depends on the attached amount of PBQ and CS concentration. Maximum grafting efficiency (GE %) and chitosan add-on percentage were 98.6% and 14.8% respectively using 0.3% CS at 40 °C for 3h.

Conclusions: Novel pH sensitive hydrogel microcapsules were prepared via grafting of chitosan molecules on to activated alginate backbone. The formulated microcapsules can be applied as a new pH sensitive carrier for protein drugs.


Keywords: Alginate, Chitosan, Polyelectrolyte complex, Hydrogel, Grafting, Activation


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How to Cite
Ms., M. E., O. Am., W. Ma., T. Tm., A. E. Ms., and I. Sa. “NOVEL SMART PH SENSITIVE CHITOSAN GRAFTED ALGINATE HYDROGEL MICROCAPSULES FOR ORAL PROTEIN DELIVERY: I. PREPARATION AND CHARACTERIZATION”. International Journal of Pharmacy and Pharmaceutical Sciences, Vol. 7, no. 11, Aug. 2015, pp. 320-6,
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