Surface clinical applications

Moreover, it has been noticed that in clinical applications, devices such as catheters, which have to pass through the skin from the outside to the interior of the body. It always exposes the patient to the risk of infection. Because there are dead space between the catheter surface and the surrounding tissue, the bacteria can enter the body along the device surface in direct contact with the skin. Such dead space would not be formed if the material surface were able to bond to the skin tissue at the microscopic level. 

To improve the biomedical properties of SPUs, a number of attempts have so far been proposed. In particular, surface modifications by mobile, hydrophilic polyethylene glycol) (PEG) chains were extensively studied, and some of them proved to give fairly good results in terms of the antithrombogenicity. Nevertheless, as discussed in Sect. 3.1, the effect of PEG chains tethered onto the SPU surface should be carefully evaluated in detail with regard to clinical application as well as to fundamental considerations. 

A variety of researches on bio-conjugate (or bio-mimicking) materials have been carried out during the last few years. As seen in Table 1, the aims and scope of many of the researchers are directly connected with clinical applications. For instance, endothelial-cell seeding (or sodding) on the luminal surface of vascular grafts is a widely-known technique [165-169] for improving the blood compatibility of polymetric materials. On the other hand, not a few of researchers are oriented to the exploitation of future possibilities of biomaterials. 

Since the late seventies, the clinical application of cisplatin has increased enormously16-18), mainly as a result of improved administration procedures and its use in combination therapy, i.e. the simultaneous application of a variety of synergistic antitumor drugs. Nowadays, usually a dosage per patient of about 100 mg of cisplatin per m2 body surface area, dissolved in saline, is given intravenously every month by standard administration protocols. 

It is of prime importance to establish the assessment method relevant to the expected clinical application of biomaterials when they are to be studied for improvement of the surface blood compatibility. A large hurdle preventing... 

Okano and coworkers have patterned poly(N-isopropylacryl-amide) (PNIPAAm), a material similar to BSA and PEG in that it does not adhere to cells at room temperature. In this experiment, a composite solution of PNIPAAm dissolved in propanol (55 wt%) was uniformly coated inside a commercial cell culture dish. The polymer was then patterned, using standard e-beam lithography, onto the surface of a cell culture dish to test the dynamic behavior of cells for potential clinical applications. A metal mask (60 mm o.d. 

Acid etching pretreatment of enamel, such as the use of buffered 50% phosphoric acid solutions, has found clinical applications to bond enamel to restorative materials, sealants and orthodontic brackets (4, ). The etching creates an increased enamel surface area and opens pores into which the resin can flow. Greater porosity of the substrate allows an easier ingress of un-... 

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