A novel approach to determine the molecular overlap of polyelectrolyte using an ultrafiltration membrane

Recovery of Phenolic Compounds and Carbohydrates from Hydro-ethanolic Extract of Zizyphus lotus Fruit using Ultrafiltration Process

Cross flow ultrafiltration (UF) using a cellulose membrane (cut off of 5 kDa) was employed to separate phenolic compounds from carbohydrates of hydro-ethanolic extract obtained fromZizyphus lotusfruit. The performance of the UF membrane was evaluated in terms of permeate flux, fouling index and retention values of total phenolic compounds, carbohydrates and uronic acid contents. The results showed that at VRF of 4.5, the membrane gave the highest rejections towards carbohydrates (99.89 %) and uronic acids (82.8 %) and the lowest average rejection of total phenolic compounds (3.12 %). Moreover, the permeate fraction exhibited the highest 2,2-diphenyl-1-picrylhydrazyl free radical scavenging ability and total antioxidant capacity with 0.036 mg.mL−1and 102.145(mgGAE.g−1DM), respectively. This result is due to the presence of phenolic compounds (gallic acid, syringic acid, catechin, quercetin and kaempferol) as identified by HPLC system. Besides, a low rejection values of the UF membrane concerning these compounds were confirmed by liquid chromatography analyses.

Automated in-line mixing system for large scale production of chitosan-based polyplexes

Chitosan (CS)-based polyplexes are efficient non-viral gene delivery systems that are most commonly prepared by manual mixing. However, manual mixing is not only poorly controlled but also restricted to relatively small preparation volumes, limiting clinical applications. In order to overcome these drawbacks and to produce clinical quantities of CS-based polyplexes, a fully automated in-line mixing platform was developed for production of large batches of small-size and homogeneous CS-based polyplexes. Operational conditions to produce small-sized homogeneous polyplexes were identified. Increasing mixing concentrations of CS and nucleic acid was directly associated with an increase in size and polydispersity of both CS/pDNA and CS/siRNA polyplexes. We also found that although the speed of mixing has a negligible impact on the properties of CS/pDNA polyplexes, the size and polydispersity of CS/siRNA polyplexes are strongly influenced by the mixing speed: the higher the speed, the smaller the size and polydispersity. While in-line and manual CS/pDNA polyplexes had similar size and PDI, CS/siRNA polyplexes were smaller and more homogenous when prepared in-line in the non-laminar flow regime compared to manual method. Finally, we found that in-line mixed CS/siRNA polyplexes have equivalent or higher silencing efficiency of ApoB in HepG2 cells, compared to manually prepared polyplexes.