Robbins Mary E, Hopper Erin D, Schoenfisch Mark H
Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, USA.
Langmuir. 2004 Nov 9;20(23):10296-302. doi: 10.1021/la048368n.
Diazeniumdiolate-modified sol-gel microarrays capable of releasing low levels of nitric oxide are reported as a viable means for improving the blood compatibility of a surface without fully modifying the underlying substrate. Several parameters are characterized including: (1) NO surface flux as a function of sol-gel composition and microarray geometry; (2) microstructure dimensions and spacing for optimal blood compatibility; and (3) the effect of sol-gel surface modification on analyte accessibility to platinum electrodes. The sol-gel microarrays release biologically relevant levels of NO under physiological conditions for >24 h. In vitro platelet adhesion assays indicate that a NO surface flux of 2.2 pmol cm(-2) s(-1) effectively reduces platelet adhesion to glass substrates modified with sol-gel microstructures separated by 50 microm. The blood compatibility observed for these micropatterned surfaces is comparable to NO-releasing sol-gel films. When the separation between NO-releasing microstructures is reduced to 10 microm, the NO surface flux required to reduce platelet adhesion is lowered to 0.4 pmol cm(-2) s(-1). Finally, the oxygen response of platinum electrodes modified with NO-releasing sol-gel microarrays indicates that selective modification via micropatterning enhances analyte accessibility to the sensor surface.
据报道，能够释放低水平一氧化氮的重氮二醇盐修饰的溶胶-凝胶微阵列是一种在不完全修饰底层基底的情况下改善表面血液相容性的可行方法。对几个参数进行了表征，包括：(1)作为溶胶-凝胶组成和微阵列几何形状函数的一氧化氮表面通量；(2)实现最佳血液相容性的微观结构尺寸和间距；(3)溶胶-凝胶表面修饰对分析物与铂电极可及性的影响。溶胶-凝胶微阵列在生理条件下可释放具有生物学相关性的一氧化氮水平超过24小时。体外血小板粘附试验表明，2.2皮摩尔·厘米-2·秒-1的一氧化氮表面通量可有效降低血小板对由50微米间隔的溶胶-凝胶微结构修饰的玻璃基底的粘附。这些微图案化表面观察到的血液相容性与释放一氧化氮的溶胶-凝胶膜相当。当释放一氧化氮的微结构之间的间距减小到10微米时，降低血小板粘附所需的一氧化氮表面通量降至0.4皮摩尔·厘米-2·秒-1。最后，用释放一氧化氮的溶胶-凝胶微阵列修饰的铂电极的氧响应表明，通过微图案化进行的选择性修饰增强了分析物与传感器表面的可及性。
