基於流通式電容式感測器之聚合物薄膜纖維蛋白原吸附行為的即時監測與特性分析

Abstract

為了以簡單、快速、即時的判斷何種聚合物材料能有最少量的纖維蛋白原吸附，以作為人體植入物材料的參考，本研究開發一套自動化電容感測平台，系統結合高靈敏度電容式生物感測器與針筒幫浦(syringe pump)，搭配 LabView 控制程式，以電容值變化即時監測纖維蛋白原於三種薄膜材料—聚四氟乙烯（polytetrafluoroethylene，PVDF）、聚對苯二甲酸乙二酯（polyethylene terephthalate，PET）與聚偏二氟乙烯（polyvinylidene difluoride，PTFE）的表面吸附行為。實驗亦透過水接觸角量測評估各材料表面親、疏水性，並以水接觸角作為另一種纖維蛋白原吸附的對照方法，進而分析各種材料的吸附能力。 電容感測器以頻率16.1 Hz 並以 120 次/分鐘的取樣頻率進行即時感測，實驗結果顯示，依據 pH 7.4 纖維蛋白原吸附於不同材料上所造成的電容值變化，可以識別出纖維蛋白原吸附於各材質表面的吸附量: PVDF > PET > PTFE，纖維蛋白原吸附於 PVDF 的最大電容值變化為 19.84 fF，於 PET 的最大電容值變化為 14.06 fF，而於 PTFE 的最大電容值變化為 11.77 fF；實驗結果擬合 Langmuir 吸附曲線的 C1/2 值分別為 PET: 0.011 mg/mL，PVDF: 0.0099 mg/mL，PTFE: 0.015 mg/mL；各材質的水接觸角 PTFE > PVDF > PET，分別為107.82°、91.07°、75.80°，與纖維蛋白原吸附於各材質表面的電容值變化不同，蛋白質吸附應與疏水性程度呈正相關，而造成 PTFE 為三者之中纖維蛋白原吸附量最低的情況主因為 PTFE 之水接觸角已超過 100°，導致纖維蛋白原吸附量不佳。 本自動化電容感測平台具備即時、簡單、快速量測之優勢，未來可應用於生物相容性材料篩選與生醫感測器開發，盼能為生醫材料的選擇上提供另一種研究方法。

To enable a simple, rapid, and real-time evaluation of polymer materials with minimal fibrinogen adsorption for use as reference materials in biomedical implants, this study developed an automated capacitive sensing platform. The system integrates a high-sensitivity capacitive biosensor with a syringe pump, controlled via a LabVIEW-based program, to monitor in real time the adsorption behavior of fibrinogen on three polymer thin-film materials: polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), and polyvinylidene difluoride (PVDF). Surface wettability of each material was evaluated through water contact angle measurements, which were used as a comparative method for fibrinogen adsorption to further analyze the adsorption characteristics of the materials. The capacitive sensor operated at a frequency of 16.1 Hz with a sampling rate of 120 samples per minute for real-time measurements. The experimental results demonstrate that, based on the capacitance changes induced by fibrinogen adsorption at pH 7.4, the adsorption amounts on different polymer surfaces can be distinguished, following the order: PVDF > PET > PTFE. The maximum capacitance changes due to fibrinogen adsorption were 19.84 fF for PVDF, 14.06 fF for PET, and 11.77 fF for PTFE. Langmuir adsorption isotherm fitting yielded half-saturation concentration (C₁/₂) values of 0.011 mg/mL for PET, 0.0099 mg/mL for PVDF, and 0.015 mg/mL for PTFE. The water contact angles of the materials followed the order PTFE > PVDF > PET, with values of 107.82 , 91.07 , and 75.80 , respectively. Unlike the trend observed in capacitance changes, protein adsorption is generally expected to increase with surface hydrophobicity. The relatively low fibrinogen adsorption on PTFE is primarily attributed to its superhydrophobic surface, where excessive hydrophobicity limits effective protein adsorption. This automated capacitive sensing platform provides the advantages of real-time, simple, and rapid measurement, and shows strong potential for future applications in biocompatible material screening and biomedical sensor development. It is expected to offer an alternative approach for the selection and evaluation of biomedical materials.