ABSTRACT
AB diblock copolymers comprised of poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) and poly(3-methacryloxypropyl trimethoxysilane) (PMTSi) segments, which are used for biocompatible coatings, were investigated. Block copolymers with various compositions were synthesized by atomic transfer radical polymerization (ATRP). The obtained copolymers were dissolved in an ethanol solution, and dynamic light scattering showed that all block copolymers were capable of existing as micelles. After a convenient "one-step" reaction, the cellulose membranes could be covalently modified by these copolymers with stable chemical bonds (C-O-Si and Si-O-Si). Block copolymers with different PMPC chain length were applied to surface modification to find the most suitable copolymer. The functional MPC density can be controlled by adjusting the ratio of the two monomers (MPC and MTSi), which also affect surface properties, including the surface contact angle, surface morphology, and number of functional PC groups. The low-fouling properties were measured by protein adsorption, platelet adhesion and activation, and cell adhesion. Protein adsorption of bovine serum albumin (BSA), fibrinogen, and human plasma were also tested and a moderate monomer composite was attained. The protein adsorption behavior on the novel interfaces depends both on MPC density and PMPC chain length. Platelet adhesion and activation were reduced on all the modified surfaces. The adhesion of Human Embryonic Kidney 293 (293T) cells on the coated surfaces also decreased.
Subject(s)
Biocompatible Materials/chemistry , Cellulose/chemistry , Chemistry, Pharmaceutical/methods , Methacrylates/chemistry , Phosphorylcholine/analogs & derivatives , Polymers/chemistry , Silanes/chemistry , Adsorption , Animals , Blood Platelets/drug effects , Cattle , Cell Adhesion , Fibrinogen/chemistry , HEK293 Cells , Humans , Micelles , Phosphorylcholine/chemistry , Platelet Adhesiveness , Proteins/chemistry , Serum Albumin/chemistry , Surface PropertiesABSTRACT
A novel organosilicon sulfobetaine was synthesized through the reaction of organosilicon containing tertiary amino with 1,3-propanesulfone. Then this organosilicon sulfobetaine was coated onto polyurethane and organosilicon surface to improve their blood compatibility. The existence of sulfobetaine structure on the surface of materials was revealed by ATR-FTIR and XPS. The thermo-capability of synthesized silicone rubber, containing sulfobetaine was revealed by TGA. The blood compatibilities of organosilicon sulfobetaine and other materials such as silicone and PU as reference coated with them were evaluated by platelet-rich plasma adhesion experiment. The novel segmented silicone rubber containing sulfobetaine structure showed perfect blood compatibility.
Subject(s)
Betaine/analogs & derivatives , Biocompatible Materials/chemistry , Biocompatible Materials/chemical synthesis , Organosilicon Compounds/chemical synthesis , Thrombosis/prevention & control , Betaine/chemistry , Coated Materials, Biocompatible/chemical synthesis , Coated Materials, Biocompatible/chemistry , Humans , Membranes, Artificial , Microscopy, Electron, Scanning , Molecular Weight , Photoelectron Spectroscopy , Platelet-Rich Plasma/metabolism , Spectroscopy, Fourier Transform Infrared , Thermogravimetry , Time FactorsABSTRACT
A p-vinylbenzyl sulfobetaine was grafted from cellulose membrane (CM) using surface-initiated atom transfer radical polymerization for blood compatibility improvement. Surface structure, wettability, morphology, and thermal stability of the CM substrates before and after modification were characterized by attenuated total reflectance Fourier transform infrared spectra, X-ray photoelectron spectroscopy measurement, water contact angle measurement, atomic force microscopy, and thermogravimetric analysis, respectively. The results showed that zwitterionic brushes were successfully fabricated on the CM surfaces, and the content of the grafted layer increased gradually with the polymerization time. The blood compatibility of the CM substrates was evaluated by protein adsorption tests and platelet adhesion tests in vitro. It was found that all the CMs functionalized with zwitterionic brush showed improved resistance to nonspecific protein adsorption and platelet adhesion, even though the grafting polymerization was conducted for several minutes.
Subject(s)
Blood , Cellulose/chemistry , Membranes, Artificial , Blood Platelets/cytology , Cell Adhesion , Humans , Magnetic Resonance Spectroscopy , Microscopy, Atomic Force , Spectroscopy, Fourier Transform InfraredABSTRACT
The chitosan/PHEA-blended hydrogels were prepared from PHEA and chitosan in various blend ratios. The water contents of the hydrogels were in the range of 50%-80% (wt). The attachment and growth of fibroblast cells(L929) on the hydrogels were studied. The results indicated the PHEA content in hydrogels has great effect on cell attachment but has little effect on the growth of L929 cells.
