應用於無稀釋血漿分離及 C-反應蛋白電化學檢測之微流體平台

A Microfluidic Platform for Undiluted Plasma Separation and Electrochemical Detection of C-Reactive Protein

賴芷萱(Zhi-Xuan Lai)

指導教授 ： 黃念祖

國立臺灣大學/電機資訊學院/生醫電子與資訊學研究所/碩士(2022年)

https://doi.org/10.6342/NTU202204203

摘要

C-反應蛋白 (CRP) 是血漿中重要的發炎反應生物標記物，可用於診斷和監測心血管疾病 (CVD)，心血管疾病長年位居全球第一大死因，若開發出可以精確量測 CRP 的定點照護 (POC) 裝置將有助於 CVD 的早期診斷。過去雖有許多文獻皆致力於開發可以精確檢測 CRP 的生物感測器，然而若要應用在 POC 環境則必須整合全血處理功能與原位生物感測，但目前僅有少數生物感測器具有整合血漿萃取功能，且未應用於 CRP 檢測。因此，在本篇論文中我們開發了整合血漿分離與電化學 CRP 檢測的微型化微流體平台。微流道部分整合了重力沉降及膜過濾兩種方式來優化血漿分離的效果。感測器部分則採用免標定的電化學生物感測器來進行原位 CRP 檢測，並優化感測器修飾步驟和電解液處理，以提高感測靈敏度及再現性。此外，為了能符合 POC 的需求，此系統的各項模組被設計的更為靈活且高度整合，在微型化的同時也更容易組裝和替換各模組元件。為驗證可行性，本研究使用此微型化微流體平台成功在 7 分鐘內從 400 µL 全血中萃取出 100 µL 無稀釋血漿，並接著使用內嵌的電化學 (EC) 感測器檢測血漿中的 CRP，檢測範圍涵蓋了臨床 CRP 濃度範圍 100 ng/mL 至 10 µg/mL。另外，該 EC 感測器也成功檢測出 1 ng/mL 至 10 µg/mL 範圍內的 CRP。上述的結果證明此高度整合的微流體平台具備應用於 POC 診斷的潛力。

關鍵字

微流體 ； 全血處理 ； 定點照護 ； 電化學量測 ； 心血管疾病

並列摘要

C-reactive protein (CRP) is an important inflammatory marker in plasma used for diagnosing cardiovascular diseases (CVDs), which have been the main cause of global mortality. A point-of-care (POC) diagnostic device for precise CRP determination can benefit the early-stage diagnosis of CVDs. Previously, various biosensors have been reported for CRP detection. However, to enable POC applications, the diagnostic device requires the integration of whole blood processing and in-situ biomarker detection. To the best of our knowledge, only a few POC-based biosensors integrate plasma extraction, and none has been reported for CRP detection. Therefore, in this thesis, we developed a miniaturized microfluidic platform integrating plasma separation with electrochemical CRP detection. To optimize the plasma separation performance, we integrate two blood separation features: (1) a sedimentation chamber and (2) a filter membrane in the microfluidic device. In the sensor part, we choose a label-free electrochemical biosensor for in-situ CRP detection. To achieve high sensitivity and reproducibility, the sensor modification and electrolyte handling protocols were optimized. Furthermore, all modules in the microfluidic platform were designed to be flexible, highly integrated, and miniaturized to achieve POC requirements. As a proof-of-concept, the microfluidic platform was successfully extracted 100 μL undiluted plasma from 400 µL whole blood within 7 min and subsequently detected CRP in the extracted plasma by an embedded electrochemical (EC) sensor in the clinical CRP range of 100 ng/mL to 10 µg/mL. In addition, the EC sensor successfully detected CRP in a broad range from 1 ng/mL to 10 µg/mL. In summary, the highly-integrated microfluidic platform shows great potential for POC diagnostics.

並列關鍵字

microfluidics ； whole blood processing ； point-of-care settings ； electrochemical detection ； cardiovascular disease

參考文獻

References

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