Hydrophilic materials have been used in many fields, but have recently garnered growing attention in biomedicine. To promote the development and use of suitable hydrophilic materials for biomedical applications, we used three hydrophilic films of varying hydrophilicity and examined the effects of their hydrophilicity on blood compatibility, protein adsorption, blood clotting time, hemolytic activity, biocompatibility, and cell attachment. Across the spectrum of hydrophilicity examined, no obvious differences in biocompatibility were observed. While high material hydrophilicity was associated with higher hemolytic activity, it still fit the nonhemolytic criteria. Further, higher hydrophilicity decreased protein adsorption and cell attachment, but increased thromboresistance in our blood clotting time assay (~30% higher blood clotting index at 10 min). These results indicate that hydrophilicity increases blood compatibility with regard to thromboresistance, but reduces cellular compatibility (i.e., cell attachment), characteristics that could be exploited for a wide range of potential applications in various fields, such as glucose electrode test strips.

We demonstrate here the application of barrel plating gold electrodes for fabricating a new type of disposable amperometric glucose biosensor. It is prepared by inserting two barrel plating gold electrodes onto an injection molding plastic base followed by immobilizing with a bioreagent layer and membrane on the electrode surface. The primary function of barrel plating is to provide an economical way to electroplate manufactured parts. The manufacture procedure is simple and can increase the fabrication precision for automation in mass production. At the two-electrode system, the detection of glucose is linear up to 800 mg/dL (i.e., 44.5 mM, r(2) > 0.99) in pH 7.4 PBS with a sensitivity of 0.71 microA/mM. Excellent sensor-to-sensor reproducibility shows coefficients of variation of only 0.8-1.4% for the detection of 56.5-561.0 mg/dL glucose. In laboratory trials 176 capillary blood samples with a range of 30-572 mg/dL glucose are used to evaluate the clinical application of the biosensor. A good linear correlation is observed between the measured values of the proposed biosensor and laboratory reference. Error grid analysis verifies that the proposed technique is promising in fabricating biosensor strips on a mass scale. As successfully demonstrated by using whole blood glucose as a model analyte, the fabrication technique can extend into other barrel plating noble metal electrodes for various applications.

No abstract