In this study, insulin-loaded nanoparticles (NPs) were prepared via self-gelation method using chitosan and aqueous soluble snail mucin as natural polymers. Herein, mucins were ionically interacted with chitosan at different concentrations to obtained insulin-loaded NPs, labelled as A1 (1:1) (i.e., chitosan 2 % w/v + mucin 2 % w/v) and A2 (2:1) (chitosan 4 % w/v + mucin 2 % w/v), using poloxamer and poly vinyl alcohol as solid surfactant. Such formulation was selected to provide the necessary dynamics for the formation of the nanoparticles while maintaining the surface properties that will favor the encapsulation of insulin. Each system was characterized in terms of their particle size distribution, morphology, zeta potential, and polydispersity index. In vitro release of insulin was evaluated in acidic solution (pH 1.2) and phosphate buffer solution (pH 7.4), and the hypoglycaemic activity was evaluated in diabetes rats. The prepared insulin-loaded NPs displayed particles with relatively smooth surfaces and an average particle size of 479.6 and 504.1 nm for A1 and A2, respectively. Zeta potential and polydispersity index, ranged from 22.1-31.2 mV and 0.155-0.185, respectively. The encapsulating efficiency for the systems A1 and A2 were 88.6 and 92.5, respectively, and a self-sustained release of encapsulated insulin was observed for over a period of 8 h. In vivo studies revealed a pronounced hypoglycaemic effect in diabetic rats after peroral administration of the insulin-loaded NPs compared to the effect caused by free oral insulin solution. In addition, both the pharmacokinetic and toxicity results showed low plasma clearance of insulin and no signs of toxicity on the liver enzyme and cell viability, which suggested good biocompatibility of the NPs formulations. Overall, the formation of NPs of insulin with chitosan and snail mucin represents a potentially safe and promising approach to protect insulin and enhance its peroral delivery.

The sole objective of this work was to design successful dosage oral forms of diclofenac sodium (DiNa)-loaded solid lipid microparticles (SLM) based on solidified reverse micellar solution (SRMS). Hot homogenization technique was employed to prepare DicNa SLM using a mixture goat fat and Phospholipon® 90 G as lipid matrix and Tween®-80 as mobile surfactant. Characterization based on percentage yield, morphology, particle size, zeta potential, percentage encapsulation, pH and stability of SLMs were investigated. Anti-inflammatory, gastrointestinal tract (GIT) sparing effect and pharmacokinetics were carried out in rat model after oral administration. Results showed that the SLMs were spherical and smooth. The optimized formulation (SLM-4) had particle size of 79.40 ± 0.31 µm, polydispersity index of 0.633 ± 0.190, zeta potential of -63.20 ± 0.12 mV and encapsulation efficiency of 91.2 ± 0.1% with good stability after 8 months of storage. The DicNa SLM had sustained release effect with good anti-inflammatory activity. Higher and prolonged plasma DicNa concentration was shown by the SLM-4 compared to pure drug and a conventional sample. These studies demonstrate that DicNa-loaded SLM based on SRMS could be a promising oral formulation for enhanced bioavailability, pharmacologic activity and gastrointestinal sparing effect of the NSAID, DicNa.

Background The aim of the study was to evaluate the suitability of triclosan (TCS) and flurbiprofen (FLB) with poly-ε-caprolactone (PCL), chitosan (CS), and Kolliphor® P188 (KP) for possible application in the design of nano-formulations. Results Differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), and scanning electron microscopy (SEM) revealed the physical characteristics of the various sample compositions without any apparent interaction. The Fourier transform infrared spectroscopy (FTIR)’s spectra of the physical mixtures showed their characteristic absorption bands with broadening and overlapping of bands in some instances, but no appearance of new bands was observed. Conclusion The study revealed the physical form stability of the evaluated components after the storage period and lack of definite pharmaceutical incompatibility between them. Thus, the selected drugs and excipients could be used for the development of pharmaceutical nano-formulations.

In this study, different ratios of mucin-grafted polyethylene-glycol-based microparticles were prepared and evaluated both in vitro and in vivo as carriers for the oral delivery of insulin. Characterization measurements showed that the insulin-loaded microparticles display irregular porosity and shape. The encapsulation efficiency and loading capacity of insulin were >82% and 18%, respectively. The release of insulin varied between 68% and 92% depending on the microparticle formulation. In particular, orally administered insulin-loaded microparticles resulted in a significant fall of blood glucose levels, as compared to insulin solution. Subcutaneous administration showed a faster, albeit not sustained, glucose fall within a short time as compared to the polymeric microparticle-based formulations. These results indicate the possible oral delivery of insulin using this combination of polymers.

To overcome barriers and improve oral bioavailability of insulin delivery has been a mirage to formulation scientists due to instability of the insulin after oral administration. Microparticle (MP) composed of chitosan and snail mucin was prepared via double emulsion method for oral delivery of insulin. Microparticles were characterized by differential scanning calorimetry, Fourier transform infrared spectroscopy and scanning electron microscopy. The encapsulation efficiency (EE) of the insulin-loaded MPs were evaluated. Insulin release behavior was evaluated in acidic and phosphate buffer (pH 1.2 and 7.4) at 37 °C. Bioactivities of insulin-loaded MPs were evaluated in a diabetic animal model after oral administration. The insulin-loaded MPs showed irregular shape with a zeta potential (>29 mV). The encapsulation efficiency and drug loading were >75 and 28 %, respectively. The in vitro release shows >80 % release of insulin over 12 h in a sustained manner. The insulin-MPs significantly reduced blood glucose levels (>50 %) compared to positive control and the effect lasted for over 8 h. This study suggests that insulin-MPs as prepared would be potential carriers for oral delivery of insulin.