Electrospun Cellulose Acetate Fiber Mats as Carriers for Crude Extracts From Phyllanthus Emblica Linn. Fruits

Fruit of Phyllanthus emblica Linn (PE) was extracted with methanol and then partitioned into diethyl ether, ethyl acetate, butanol, and water fractions. The diethyl ether fraction showed the highest antibacterial activity against two pathogenic bacteria including Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923). The PE extract from diethyl ether fraction was then loaded into 17%w/v cellulose acetate (CA) solution prepared in 2:1 v/v acetone/N, N-dimethylacetamide at concentrations of 1, 3, and 5% w/w (based on the weight of CA). The PE extract-loaded electrospun CA fiber mats were fabricated by electrospinning. The morphological appearance of both the neat and the PE extract-loaded electrospun CA fibers were smooth with the average diameters in a range of 335-694 nm. The amounts of water retention and release characteristics of PE extract from fiber mats in an acetate buffer (pH 5.5) were studied and compared with the corresponding cast-films fabricated by the solvent casting method. The amount of water retention of the PE extract-loaded fiber mats was about 112-205% which was higher than that of the cast films (i.e. 25-35%). The study of release characteristics of PE extract from fiber mats and films was carried out by total immersion method in an acetate buffer at 32°C for 72 h. The PE extract-loaded fiber mats exhibited greater amount of extract released than those of the cast films. The maximum amounts of PE extract released from fiber mats and films were about 40-80% and 18-23%, respectively

Electrospun poly(bisphenol A-co-4-nitrophthalic anhydride-co-1,3-phenylenediamine) fibers: Preparation and potential for use in filtration applications

Poly(bisphenol A-co-4-nitrophthalic anhydride-co-1,3-phenylenediamine) (PEI) fibers were successfully prepared byelectrospinning from PEI solutions in dichloromethane (DCM), 1,2-dichloroethane (DCE), N-methylpyrrolidone (NMP) andcertain mixtures between NMP and N,N-dimethylformamide (DMF). Electrospinnability of PEI solutions in NMP was greaterthan that in DCM and DCE. The addition of DMF with NMP for the preparation of PEI solutions helped improve electrospinnabilityof the PEI solutions. The effect of solution concentration on morphological appearance and/or size of the obtainedproducts was investigated. At low concentrations of the PEI solutions, discrete beads and/or beaded fibers was formed.Smooth fibers were obtained at the highest concentration investigated, i.e., 20% (w/v). The size of the obtained fibers wasfound to be an increasing function with the solution concentration or, to be exact, the solution viscosity. The water fluxesthrough the electrospun fiber mats prepared from 20% (w/v) PEI solutions in 75/25 and 50/50 NMP/DMF mixtures wereinvestigated in comparison with the films prepared by phase immersion-precipitation technique. The fiber mats exhibitedmuch greater fluxes of water than the films, which implied their potential for uses as filtration membranes

Electrospun Cellulose Acetate Fiber Mats as Carriers for Crude Extracts From Phyllanthus Emblica Linn. Fruits

Fruit of Phyllanthus emblica Linn (PE) was extracted with methanol and then partitioned into diethyl ether, ethyl acetate, butanol, and water fractions. The diethyl ether fraction showed the highest antibacterial activity against two pathogenic bacteria including Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923). The PE extract from diethyl ether fraction was then loaded into 17%w/v cellulose acetate (CA) solution prepared in 2:1 v/v acetone/N, N-dimethylacetamide at concentrations of 1, 3, and 5% w/w (based on the weight of CA). The PE extract-loaded electrospun CA fiber mats were fabricated by electrospinning. The morphological appearance of both the neat and the PE extract-loaded electrospun CA fibers were smooth with the average diameters in a range of 335-694 nm. The amounts of water retention and release characteristics of PE extract from fiber mats in an acetate buffer (pH 5.5) were studied and compared with the corresponding cast-films fabricated by the solvent casting method. The amount of water retention of the PE extract-loaded fiber mats was about 112-205% which was higher than that of the cast films (i.e. 25-35%). The study of release characteristics of PE extract from fiber mats and films was carried out by total immersion method in an acetate buffer at 32°C for 72 h. The PE extract-loaded fiber mats exhibited greater amount of extract released than those of the cast films. The maximum amounts of PE extract released from fiber mats and films were about 40-80% and 18-23%, respectively