PEGylated polymeric nanocapsules for oral delivery of trypsin targeted to the small intestines.

The lack of trypsin in the intestines may end up with malnutrition; thus, trypsin replacement therapy is required in such cases. The main objective of this study is to formulate and evaluate polymeric nanocapsule (PNC) systems able to deliver trypsin to the small intestines with the minimal release in the stomach with the maximum biological activity. Four nanocapsule formulations were prepared by double emulsion/evaporation method as w/o/w and s/o/w. Particle size, encapsulation efficiencies, drug release in simulated gastric fluids (SGF) and simulated intestinal fluids (SIF), morphology, the biological activity of encapsulated trypsin and shelf-life stability were investigated for all formulations. All formulations had a spherical shape with submicron size, and encapsulation efficiency more than 80%. The biological activity of encapsulated trypsin was significantly affected by the amount of trehalose and whether the formulations were prepared as s/o/w or w/o/w (P < 0.05). Most of the encapsulated protein was released sustainedly at the target site (SIF) over 24 h with minimum amount release in the gastric fluids. Also, more than 90% of physical integrity trypsin encapsulated in all formulations was retained after storage under chilled conditions for six months. However, the enzymatic assay results show that with low trehalose content, the biological activity was low, while increasing the trehalose amount increased the shelf stability to reach around 100% after six months of the study. The results obtained in this research work clearly indicated a promising potential of controlled release polymeric nanocapsules containing trypsin to target the small intestine and protect trypsin from the harsh condition facing the proteins during the process of preparation or the period of storage.

Synthesis of new pyrazolone and pyrazole-based adamantyl chalcones and antimicrobial activity.

Chalcones and their derivatives are becoming increasingly popular due to their various pharmacological effects. Chalcone molecules may be extracted from natural resources, entirely synthesised, or biosynthesised by modifying the natural ones. In the present study, five pyrazole-based adamantyl heterocyclic compounds were synthesised by condensation of 1-adamantyl chalcone with substituted phenylhydrazine. The products were characterised by using ¹H NMR, ¹³C NMR and FT-IR spectroscopy. The microbiological activity of these compounds was investigated against bacteria and fungi. The new compounds showed good to moderate activity against the microbial species used for screening. All developed molecules showed antibacterial activity against Gram-negative and Gram-positive. These molecules showed antifungal activities against Fusarium oxysporum fungus and in a dose-dependent manner, apart from RS-1 molecules which showed compromised antifungal activity and even at a high dose.

Design of experiment (DoE)-driven in vitro and in vivo uptake studies of exosomes for pancreatic cancer delivery enabled by copper-free click chemistry-based labelling.

Exosomes (Exo)-based therapy holds promise for treatment of lethal pancreatic cancer (PC). Limited understanding of key factors affecting Exo uptake in PC cells restricts better design of Exo-based therapy. This work aims to study the uptake properties of different Exo by PC cells. Exo from pancreatic carcinoma, melanoma and non-cancer cell lines were isolated and characterised for yield, size, morphology and exosomal marker expression. Isolated Exo were fluorescently labelled using a novel in-house developed method based on copper-free click chemistry to enable intracellular tracking and uptake quantification in cells. Important factors influencing Exo uptake were initially predicted by Design of Experiments (DoE) approach to facilitate subsequent actual experimental investigations. Uptake of all Exo types by PC cells (PANC-1) showed time- and dose-dependence as predicted by the DoE model. PANC-1 cell-derived exosomes (PANC-1 Exo) showed significantly higher uptake in PANC-1 cells than that of other Exo types at the longest incubation time and highest Exo dose. In vivo biodistribution studies in subcutaneous tumour-bearing mice similarly showed favoured accumulation of PANC-1 Exo in self-tissue (i.e. PANC-1 tumour mass) over the more vascularised melanoma (B16-F10) tumours, suggesting intrinsic tropism of PC-derived Exo for their parent cells. This study provides a simple, universal and reliable surface modification approach via click chemistry for in vitro and in vivo exosome uptake studies and can serve as a basis for a rationalised design approach for pre-clinical Exo cancer therapies.

Lysozyme and DNase I loaded poly (D, L lactide-co-caprolactone) nanocapsules as an oral delivery system.

Clinical applications of oral protein therapy for the treatment of various chronic diseases are limited due to the harsh conditions encounter the proteins during their journey in the Gastrointestinal Tract. Although nanotechnology forms a platform for the development of oral protein formulations, obtaining physiochemically stable formulations able to deliver active proteins is still challenging because of harsh preparation conditions. This study proposes the use of poly (D, L-lactic-co-caprolactone)-based polymeric nanocapsules at different monomers' ratios for protein loading and oral delivery. All formulations had a spherical shape and nano-scale size, and lysozyme encapsulation efficiency reached 80% and significantly affected by monomers' ratio. Trehalose and physical state of lysozyme had a significant effect on its biological activity (P < 0.05). Less than 10% of the protein was released in simulated gastric fluid, and 73% was the highest recorded accumulative release percentage in simulated intestinal fluid (SIF) over 24 h. The higher caprolactone content, the higher encapsulation efficiency (EE) and the lower SIF release recorded. Therefore, the formulation factors were optimised and the obtained system was PEGylated wisely to attain EE 80%, 81% SIF release within 24 h, and 98% lysozyme biological activity. The optimum formulation was prepared to deliver DNase, and similar attributes were obtained.