Eudragit S100 entrapped insulin microspheres for oral delivery

Abstract

The purpose of this research was to investigate whether Eudragit S100 microspheres have the potential to serve as an oral carrier for peptide drugs like insulin. Microspheres were prepared using water-in oil-in water emulsion solvent evaporation technique with polysorbate 20 as a dispersing agent in the internal aqueous phase and polyvinyl alcohol (PVA)/polyvinyl pyrrolidone as a stabilizer in the external aqueous phase. The use of smaller internal aqueous-phase volume (50 mL) and external aqueous-phase volume (25 mL) containing PVA in the manufacturing process resulted in maximum encapsulation efficiency (81.8% 6 0.9%). PVA-stabilized microspheres having maximum drug encapsulation released 2.5% insulin at pH 1.0 in 2 hours. In phosphate buffer (pH 7.4), microspheres showed an initial burst release of 22% in 1 hour with an additional 28% release in the next 5 hours. The smaller the volumes of internal and external aqueous phase, the lower the initial burst release. The release of drug from microspheres followed Higuchi kinetics. Scanning electron microscopy of PVA-stabilized microspheres demonstrated spherical particles with smooth surface, and laser diffractometry revealed a mean particle size of 32.51 6 20 mm. Oral administration of PVA stabilized microspheres in normal albino rabbits (equivalent to 6.6 IU insulin/kg of animal weight) demonstrated a 24% reduction in blood glucose level, with maximum plasma glucose reduction of 76 6 3.0% in 2 hours and effect continuing up to 6 hours. The area under the percentage glucose reduction-time curve was 93.75%. Thus, our results indicate that Eudragit S100 microspheres on oral administration can protect insulin from proteolytic degradation in the gastrointestinal tract and produce hypoglycemic effect.

Enhanced oral bioavailability of insulin-loaded solid lipid nanoparticles: pharmacokinetic bioavailability of insulin-loaded solid lipid nanoparticles in diabetic rats

“…Insulin administered via the oral route will help eliminate the pain caused by injection, psychological barriers associated with multiple daily injections, such as needle anxiety (Korytkowski, 2002) and possible infections (Lin et al, 2007). However, being a protein, it undergoes rapid enzymatic degradation in the stomach, inactivation and digestion by proteolytic enzymes in the intestinal lumen (Patki & Jagasia, 1996;Agarwal & Khan, 2001, Nakamura et al, 2004Jain et al, 2005;Sajeesh & Sharma 2006). Another major barrier to the absorption of hydrophilic macromolecules like insulin is that they cannot diffuse across epithelial cells through lipid-bilayer cell membranes to the blood stream (Lin et al, 2007).…”

A Review on Cuminosides Nanomedicine-: Pharmacognostic approach to Cancer therapeutics

“…During this time cuminosides release from the formulation is 1/3 that of free cuminosides, yet nanoformulations still exhibit equivalent or slightly greater anticancer potentials. However, their improved efficacy can be observed in long term experiments (such as colony formation) 41,39,42,43,45 as well as in animal model. 38 Cationic poly(butyl) cyanoacrylate nanoparticles coated with chitosan mediated the release of cuminosides efficiently which inhibited tumor growth and tumor angiogensis.…”

Chemical Modification of Chitosan and Formulation of Its Nanoparticles for Protein Drug Delivery System

“…The amount of drug released was analyzed by UV-visible spectrophotometric bio assay. The release studies were conducted in triplicates and mean values of cumulative % drug release were plotted versus time [19][20] .…”