Sensitive detection of biomarkers will mean accurate and early diagnosis of diseases. A tissue plasminogen activator (tPA) has a crucial role in many cardiovascular diseases and it is related to many processes such as angiogenesis in cancer cells. Therefore, sensitive determination of tPA is important in diagnosis and clinical research. tPA monoclonal antibody was covalently attached onto single-wall carbon nanotubes (SWCNTs) using diimide-activated imidation coupling. Functionalized SWCNTs were immobilized onto a glassy carbon electrode and the modification process was investigated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), SEM, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). Cyclic voltammograms (CVs) in a scan rate of 100 mVs⁻¹ was studied and comparisons were made between the modified glassy carbon electrodes (immobilized with antibodies) as a working electrode before and after the formation of tPA-antibody complex. Results of the SDS-PAGE demonstrated that the antibody was covalently and site directly attached to the SWCNTs. The fabricated biosensor provided a good linear response range from 0.1 to 1.0 ng mL⁻¹ with a low detection limit of 0.026 ng mL⁻¹. The immunosensor showed selectivity, reproducibility, good sensitivity, and acceptable stability. Satisfactory results were observed for early and sensitive determination of tPA in human serum samples. For the first time, such specific biosensor is currently being fabricated for tPA in our laboratories and successfully could determine tPA in myocardial infraction and breast cancer patients.

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对生物标志物的敏感检测将意味着对疾病的准确和早期诊断。组织纤溶酶原激活剂（tPA）在许多心血管疾病中都起着至关重要的作用，并且与许多过程有关，例如癌细胞中的血管生成。因此，tPA的敏感测定在诊断和临床研究中很重要。使用二酰亚胺激活的酰亚胺化偶联将tPA单克隆抗体共价连接到单壁碳纳米管（SWCNT）上。将功能化的SWCNTs固定在玻璃碳电极上，并通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE），SEM，循环伏安法（CV）和电化学阻抗谱（EIS）研究修饰过程。扫描速度为100 mVs ^-1的循环伏安图（CV）对tPA-抗体复合物形成前后的修饰玻碳电极（固定有抗体）作为工作电极进行了比较。SDS-PAGE的结果表明该抗体是共价的并且位点直接附着于SWCNT。所制造的生物传感器提供了从0.1到1.0 ng mL ^-1的良好线性响应范围，以及0.026 ng mL ^-1的低检测限。免疫传感器显示出选择性，可重复性，良好的灵敏度和可接受的稳定性。对于人血清样品中tPA的早期和灵敏测定，观察​​到令人满意的结果。目前，我们实验室首次为tPA制造了这种特殊的生物传感器，并成功地确定了心肌梗塞和乳腺癌患者的tPA。

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