Lentinan

a mushroom polysaccharide

isolated from Lentinus edodes (Shiitake mushroom) was carboxymethylated in NaOH and isopropanol solution to obtain a water-soluble derivative.Then

carboxymethylated lentinan was covalently immobilized onto the surface of aminated poly(lactic acid) (PLA) substrates via chemical grafting method.In addition

carboxymethylated lentinan and chitosan were alternatively deposited on the aminated PLA substrates via layer-by-layer (LbL) assembly method

in order to construct a polysaccharide-based multilayer on the substrates.The carboxymethylated lentinan was proved by infrared spectroscopy.The degree of substitution and molecular weight (Mw) of carboxymethylated lentinan were determined by UV spectrophotometry and gel permeation chromatography (GPC)

respectively.The modified and unmodified PLA surfaces were investigated by scanning electron microscope (SEM) and water contact angle measurements.The hemolysis test

thrombus test

and the antibacterial activity against Escherichia coli of modified and unmodified PLA were tested in vitro

respectively.Then

the surface properties of PLA modified by different modification methods were evaluated and compared.The results showed that the hydrophilicity

blood compatibility

and antibacterial activity against Escherichia coli of PLA modified by LbL assembly and chemical grafting were both improved.In addition

PLA modified by carboxymethylated lentinan and chitosan through LbL assembly method showed better hydrophilicity

blood compatibility

and antibacterial activity against Escherichia coli

in comparison with that modified by chemical grafting method.