Biomedical subjects

Yan-lei Su

Publications and source records attributed to Yan-lei Su.

4 recordsLinked to original sources

PubMed2005

Improved protein-adsorption-resistant property of PES/SPC blend membrane by adjustment of coagulation bath composition.

To improve surface protein-adsorption-resistant property of polyethersulfone (PES) membranes, soybean phosphatidylcholine (SPC) was added to PES casting solution. The blend membranes were prepared by a phase inversion method in a wet process. The surface of PES/SPC blend membranes was characterized by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). XPS data revealed that the phosphorylcholine (PC) groups were concentrated at the surface by changing the composition of coagulation bath. Addition of N,N-dimethylformamide (DMF) in coagulation bath could prolong coagulation time and facilitate the migration of SPC from polymer bulk to membrane surface. The PES/SPC blend membranes dramatically reduced BSA and fibrinogen adsorption compared to PES control membrane due to effective immobilization of PC groups at the surface of PES/SPC blend membranes.

Adsorption↗

PubMed2005

Remarkable reduction of irreversible fouling and improvement of the permeation properties of poly(ether sulfone) ultrafiltration membranes by blending with pluronic F127.

Hydrophilic modification of ultrafiltration membranes was achieved through blending of Pluronic F127 with poly(ether sulfone) (PES). The chemical composition and morphology changes of the membrane surface were confirmed by water contact angle, X-ray photoelectron spectroscopy, scanning electron microscopy, and protein adsorption measurements. The decreased static water contact angle with an increase in the Pluronic F127 content indicated an increase of surface hydrophilicity. XPS analysis revealed enrichment of PEO segments of Pluronic F127 at the membrane surface. The apparent protein adsorption amount decreased significantly from 56.2 to 0 microg/cm(2) when the Pluronic F127 content varied from 0% to 10.5%, which indicated that the blend membrane had an excellent ability to resist protein adsorption. The ultrafiltration experiments revealed that the Pluronic F127 content had little influence on the protein rejection ratio and pure water flux. Most importantly, at a high Pluronic F127 content membrane fouling, especially irreversible fouling, has been remarkably reduced. The flux recoveries of blend membranes reached as high as 90% after periodic cleaning in three cycles.

Ether↗

PubMed2005

Assembly of polydiacetylene vesicles on solid substrates.

A method to create assembly of polydiacetylene vesicles on solid substrates in a novel fashion is described. The formation of the assembly is based on electrostatic layer-by-layer deposition using negatively charged 10,12-pentacosadiynoic acid (PCDA) vesicles and polyelectrolyte polyethylenimine, or positively charged PCDA-2(')-aminoethylamide (PCDANH2) vesicles. This is an efficient method for preparing the chromatic sensor films of polydiacetylene vesicles after ultraviolet light irradiation. The strategy would be useful in the development of polydiacetylene-based chemosensors and biosensors.

Journal Article↗

PubMed2004

Effect of amphiphilic molecules upon chromatic transitions of polydiacetylene vesicles in aqueous solutions.

Effect of amphiphilic molecules upon the chromatic transitions of polymerized 10,12-pentacosadiynoic acid (PCDA) vesicles in aqueous solutions was reported. The colorimetric response of polymerized PCDA vesicles for 1-pentanol is higher than that for ethanol due to more hydrophobic property of 1-pentanol. The colorimetric response of polymerized PCDA vesicles for sodium dodecyl sulfate (SDS) and Triton X-100 is lower than that for cetyltrimethylammonium bromide (CTAB). The strong ability of CTAB to induce chromatic transition of the vesicles is related to the positively charged headgroups of CTAB, which favors approach of CTAB to the negatively charged carboxylate groups at the vesicle surface. The insertion of alkyl chain of CTAB into the hydrophobic domain perturbs the conformation of the conjugated polymer backbone and induces color change of polydiacetylene vesicles. For a series of alkylamine hydrochloric salts, the longer the alkyl chain, the stronger the ability of alkylamine to induce chromatic transition of polydiacetylene vesicles.

Acetylene↗