传感器类型
综述或非传感器论文
检测对象
人血小板(human platelets)、牛纤维蛋白原(bovine fibrinogen, BFG);样品基质:富血小板血浆(PRP)、PBS缓冲液
检测原理
本文未建立针对特定分析物的传感检测原理,而是制备并评价OBCS接枝PPy薄膜。PPy由吡咯在对甲苯磺酸(PTSA)存在下于不锈钢表面恒电流电沉积形成导电膜。将4-叠氮苯甲酸修饰的OBCS(Az-OBCS)涂覆于PPy表面后,在254 nm紫外光下叠氮基团释放N2并生成高活性氮烯,与PPy表面C-H发生光交联,使OBCS共价接枝。该界面改变表面化学组成与润湿性,从而降低纤维蛋白原吸附和血小板黏附。评价通过PRP接触后SEM观察血小板形态,以及125I标记纤维蛋白原吸附后γ计数;电导率用改进四探针法测量。文中未给出分析物浓度与信号响应的定量关系。
检测灵敏度
原文未报告LOD、线性范围、灵敏度斜率或相关系数。
效应效果
未改性PPy和物理涂覆Az-OBCS-c-PPy表面均显示较高血小板黏附,且黏附血小板多变形并出现伪足;共价接枝的Az-OBCS-g-PPy表面几乎无血小板黏附。牛纤维蛋白原吸附量分别为PPy 2.827±0.083 μg/cm2、Az-OBCS-c-PPy 2.815±0.080 μg/cm2、Az-OBCS-g-PPy 1.673±0.076 μg/cm2,说明共价接枝OBCS可显著降低蛋白吸附。未改性PPy电导率约28.3±0.3 S/cm,Az-OBCS-g-PPy约27.5±0.3 S/cm,电导率未显著下降。作者认为该材料可用作导电血管和全血生物传感器的血液相容基底。
传感器的构成
- 基底:粗糙不锈钢(stainless steel)作为支撑与导电基底。
- 导电聚合物层:聚吡咯(PPy)由吡咯和对甲苯磺酸(PTSA)恒电流电沉积形成,提供高电导率。
- 光敏修饰前体:4-叠氮苯甲酸修饰的O-丁酰壳聚糖(Az-OBCS)涂覆于PPy表面,提供叠氮基团用于光交联。
- 接枝生物相容层:O-丁酰壳聚糖(OBCS)经紫外光交联共价固定于PPy表面,降低血小板黏附和纤维蛋白原吸附。
- 识别元件:未报道,未固定抗体、适配体、酶或DNA探针。
- 信号标记物:未报道,无荧光、电化学或酶促信号标记。
- 封闭剂/电子供体:未报道,无封闭剂或电子供体。
中文摘要
本文报道了一种新型O-丁酰壳聚糖(OBCS)接枝聚吡咯(PPy)薄膜。该薄膜通过紫外光照射,将OBCS光交联固定到PPy薄膜表面。作者采用衰减全反射傅里叶变换红外光谱(ATR-FTIR)和电子能谱化学分析(ESCA)对OBCS接枝PPy薄膜表面进行表征,确认OBCS成功接枝。通过富血小板血浆(PRP)接触实验和体外蛋白吸附实验评价其血液相容性。结果表明,与对照表面相比,固定OBCS的表面血小板黏附和纤维蛋白原吸附明显降低。采用改进四探针法测量PPy薄膜体相电导率。复合薄膜兼具良好血液相容性和高电导率,可作为导电血管以及可直接用于全血的生物传感器功能性血液相容基底等潜在生物材料。
英文摘要
A novel O-butyryl chitosan (OBCS)-grafted polypyrrole (PPy) film was described. The immobilization was accomplished by photocrosslinking the OBCS onto PPy films under ultraviolet light irradiation. The surfaces of OBCS-grafted PPy film were characterized by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and electron spectroscopy for chemical analysis (ESCA). The blood compatibility of the OBCS-grafted PPy film was evaluated by platelet-rich plasma (PRP) contacting experiments and protein adsorption experiments in vitro. These results have demonstrated that the surface with immobilized OBCS shows much less platelet adhesive and fibrinogen adsorption compared to the control surface. The bulk conductivity values of PPy films were measured by a modified four-probe method. The composite films have both good blood compatibility and high electrical conductivity that make them suitable for using as potential biomaterials, such as electrically conducting blood vessel and functionally haemocompatible substrate of biosensor used directly in whole blood.