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In-stent restenosis is the major problem of percutaneous coronary interventions. Drug-eluting stent became a landmark in the treatment of coronary disease. Curcumin could be used for drug-eluting stent due to its antithrombogenity and antiproliferative properties. In this paper, 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assays were performed to decide the optimal concentration of curcumin for inhibiting the proliferation of vascular smooth muscle cells (VSMC). The result disclosed that more than 80% of VSMC were inhibited when the concentration of curcumin ranged from 2.5 microg/ml to 10 microg/ml (P < 0.05, compared to ethanol). Three weight percent curcumin-loaded films (3wt%, 5wt%, 8wt%) were prepared using a biodegradable polymer (poly (lactic acid-co-glycol acid), PLGA) as the carrier of curcumin. The release of lactate dehydrogenase (LDH) was used to evaluate the immediate toxicity of the curcumin-loaded PLGA films, and the three concentration curcumin-loaded films were revealed to be of no acute toxicity to the smooth muscle cells. The results of Alamar Blue test indicated that the curcumin-loaded films had better antiproliferation effect than did the 316 stainless steel (SS). Therefore, these films may be used for stent coating to inhibit the in-stent restenosis induced by VSMC proliferation.

In-stent restenosis is the major problem in clinical application of coronary stent. Drug-eluting stent became a landmark in the treatment of coronary disease. However, thrombosis is still a problem of drug-eluting stent. There has been clinical report indicating that thrombosis sometimes is induced by drug-eluting stent implantation in late stage. Curcumin could be used for drug-eluting stent due to its antithrombogenity and antiproliferative properties. In this paper, three weight percent curcumin-loaded films (3wt%, 5wt%, 8wt%) were prepared using a biodegradable polymer (poly (lactic acid-co-glycol acid), PLGA) as the carrier of curcumin. The component of curcumin-loaded film was analyzed by Fourier transform infrared spectroscopy (FTIR), and the major peaks of curcumin and PLGA were both observed in the composite film. The result of in vitro platelet adhesion test shows that the number of adhered platelet reduces, and few aggregated and activated platelets are observed. For all composite films, activated partial thromboplastin time (APTT) increases. The results indicate that the curcumin-loaded films have better anticoagulative effect when compared with PLGA. In addition, all anticoagulation tests indicate "the higher the drug content in the film, the better the anticoagulative effect".

Diamond-like carbon (DLC) films were deposited by acetylene plasma immersion ion implantation-deposition (PIII-D) on biomedical polyethylene terephthalate (PET). The capacities of Staphylococcus aureus (SA), Staphylococcus epidermidis (SE), Escherichia coli (EC), Pseudomonas aeruginosa (PA) and Candida albicans (CA) for adhesion to PETs are quantitatively determined by the plate counting and Gamma-ray counting of 125I radio labeled bacteria in vitro. The results indicate that the capacities of five types of bacteria for adhesion to PETs are all suppressed by C2H2 PIII-D (P<0.05). The surface energy components of the various substrates and bacteria are calculated based on measurements in water, formamide and diiodomethane and Lifshitz-van del Waals/acid-base approach (LW-AB). The surface free energies obtained are used to calculate the interfacial free energies of adhesion (deltaF(adh)) of five kinds of bacteria on various substrates, and the results show that it is energetically unfavorable for bacterial adhesion to the DLC films already deposited on PET by C2H2 PIII-D.

In this paper, polyethylene glycol (PEG) of different molecular weight was grafted on the polyethylene terephthalate (PET, Dacron) films by plasma surface grafting modification. The competitive adsorption relation of plasma (fibrinogen and albumin) adsorbing on materials surface was analyzed in light of surface energy and interface free energy. The results indicated that the PET films grafted PEG long chain molecular possesses the characteristic of preferentially adsorbing albumin and this adsorption tendency of grafted PEG6000 sample is most distinct. The platelet adhesion tests of the PET films whose surfaces were pre-set in contact with fibrinogen and albumin indicated that the surface adsorbing albumin can distinctly inhibit platelet adhesion and aggregation and possess favorable blood compatibility, but the surface adsorbing fibrinogen can enhance platelet adhesion and aggregation.