Effect of Nutrient Formulations on Permeation of Proteins and Lipids through Porcine Intestine In vitro

Purpose: To investigate the effect of nutrient formulations on the permeation of proteins and lipids through porcine intestine in vitro.Method: In vitro permeation studies of proteins and lipids of two peptide-based formulations, composed of various compounds and sources of hydrolyzed protein was carried out, and compared with a conservative polymeric formulation as control, The test was undertaken using Franz diffusion cell apparatus incorporating porcine intestine.Results: The peptide-based formulation demonstrated higher protein absorption than the conservative polymeric one. However, there were some differences in protein absorption rates between the peptide based formulations obtained from various sources. Formulation A with 1.0 and 1.5 kcal/mL exhibited significantly (p < 0.05) higher cumulative protein permeation (11.97 ± 0.23 and 12.54 ± 0.94 μg/cm2) than formulations B (9.41 ± 0.36 and 9.67 ± 0.35 μg/cm2) and C (8.34 ± 0.56 and 8.61 ± 0.71 μg/cm2), respectively. Lipid permeation from formulations A and B (13.91 ± 0.26 and 12.94 ± 0.59 μg/cm2 respectively for 1.0 kcal/mL formulation, and 13.31 ± 0.21 and 12.86 ± 0.16 for 1.5 kcal/mL formulation) which consist mainly of medium chain triglycerides (MCTs), were significantly (p <0.05) higher than those from formulation C (11.49 ± 0.43 and 12.62 ± 0.38 μg/cm2 for 1.0 and 1.5 kcal/mL formulation, respectively) which mostly contained long chain triglycerides (LCTs).Conclusion: The results reveal that oligomeric formulations have higher absorption rate than polymeric formulations. However, the outcomes when administered to clinically ill patients need to be investigated.Keywords: Nutrient Formulations, Permeation, Proteins, Lipids, Porcine Intestine, Medium Chain Triglycerides, Long Chain Triglyceride

Strontium-containing, carbohydrate-based polymer networks as tooth-adherent systems for the treatment of dentine hypersensitivity

This study describes the design/physicochemical properties of strontium-containing, mucoadhesive carbohydrate polymeric platforms, designed as treatments for dentine hypersensitivity. Interactive networks were composed of strontium chloride (10% w/w), one of two base polymers (sodium carboxymethylcellulose, NaCMC or hydroxyethylcellulose, HEC), polycarbophil (PC) and, when required, polyvinylpyrrolidone (PVP). The physicochemical properties were characterised using oscillatory and flow rheometry, texture profile analysis, mucoadhesion analysis and, additionally, the strontium release properties were examined. All platforms exhibited pseudoplastic flow. Increasing polymer concentrations increased network viscoelasticity, consistency, hardness, compressibility, gel strength, adhesiveness, mucoadhesion and, retarded strontium release. Principally zero-order strontium release was observed from all platforms. Incorporation of strontium reduced the network elasticity, consistency, hardness, compressibility, gel strength and mucoadhesion; HEC-based platforms being affected to a greater extent than NaCMC platforms. NaCMC-based platforms containing 10% strontium chloride, PVP (3% w/w) and PC (3% w/w) potentially displayed the correct balance of physicochemical properties for the treatment of dentine sensitivity.<br/