Doke Atul M, Sadana Ajit
Chemical Engineering Department, University of Mississippi, University, Mississippi 38677-1848, USA.
Biotechnol Prog. 2006 Jan-Feb;22(1):14-23. doi: 10.1021/bp050118p.
A fractal analysis is used to model the binding and dissociation kinetics of connective tissue interstitial glucose, adipose tissue interstitial glucose, insulin, and other related analytes on biosensor surfaces. The analysis provides insights into diffusion-limited analyte-receptor reactions occurring on heterogeneous biosensor surfaces. Numerical values obtained for the binding and the dissociation rate coefficients are linked to the degree of heterogeneity or roughness (fractal dimension, Df) present on the biosensor chip surface. The binding and dissociation rate coefficients are sensitive to the degree of heterogeneity on the surface. For example, for the binding of plasma insulin, as the fractal dimension value increases by a factor of 2.47 from Df1 equal to 0.6827 to Df2 equal to 1.6852, the binding rate coefficient increases by a factor of 4.92 from k1 equal to 1.0232 to k2 equal to 5.0388. An increase in the degree of heterogeneity on the probe surface leads to an increase in the binding rate coefficient. A dual-fractal analysis is required to fit the binding kinetics in most of the cases presented. A single fractal analysis is adequate to describe the dissociation kinetics. Affinity (ratio of the binding to the dissociation rate coefficient) values are also presented. Interferents for glucose such as uric acid and ascorbic acid were also detected using glucose biosensors based on carbon nanotube (CNT) nanoelectrode ensembles (NEEs) (29) (Lin, Y.; Lu, F.; Tu, Y.; Ren, Z. Nano Lett. 2004, 4 (2), 191-195). Attempts are made to standardize biosensor properties in terms of diffusion characteristics on in vivo responsiveness.
分形分析用于模拟结缔组织间质葡萄糖、脂肪组织间质葡萄糖、胰岛素及其他相关分析物在生物传感器表面的结合和解离动力学。该分析有助于深入了解在异质生物传感器表面发生的扩散受限分析物 - 受体反应。结合和解离速率系数的数值与生物传感器芯片表面存在的异质性或粗糙度程度（分形维数，Df）相关。结合和解离速率系数对表面异质性程度敏感。例如，对于血浆胰岛素的结合，当分形维数从Df1 = 0.6827增加2.47倍至Df2 = 1.6852时，结合速率系数从k1 = 1.0232增加4.92倍至k2 = 5.0388。探针表面异质性程度的增加导致结合速率系数增加。在大多数情况下，需要双分形分析来拟合结合动力学。单分形分析足以描述解离动力学。还给出了亲和力（结合速率系数与解离速率系数之比）值。还使用基于碳纳米管（CNT）纳米电极阵列（NEEs）的葡萄糖生物传感器检测了葡萄糖的干扰物，如尿酸和抗坏血酸（29）（Lin，Y.；Lu，F.；Tu，Y.；Ren，Z. Nano Lett. 2004，4（2），191 - 195）。人们试图根据体内反应性的扩散特性来规范生物传感器的性能。
