請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/47608
標題: | 毛細-重力閥門及其在整合式尿液肌酸酐檢測晶片
之研究與應用 Design and Investigation of Capillary-Gravitational Valve in an Integrated Urine-Chip for Creatinine Detection |
作者: | Po-Hsuan Fang 方柏璇 |
指導教授: | 王安邦(An-Bang Wang) |
關鍵字: | 慢性腎臟病,尿液肌酸酐,定量檢測,時序控制,實驗式晶片,光學密度, Chronic Kidney Disease,Urinary Creatinine,Quantitative Analysis,Serial Process,Lab-on-a-Chip,Optical Density, |
出版年 : | 2011 |
學位: | 碩士 |
摘要: | 慢性腎臟病(chronic kidney disease)在台灣的盛行率位居全世界第二,主要是由於國人對此疾病的自知率相當低,因此發展一個居家照護的腎功能檢測裝置有其必要性。肌酸酐(creatinine)為人體定量產生之物質,其在血液及尿液中的濃度可做為判斷腎功能正常與否的標準。但抽血在居家照護之執行上有所不易,故本研究利用實驗式晶片(lab-on-a-chip)的概念,將醫院的生化分析步驟整合至可拋棄式晶片上,以定量分析尿液中的肌酸酐。又由於尿液的濃度變異度大,須加上測量其他物質誠如白蛋白(albumin)來推斷腎功能。
目前對肌酸酐之檢測,依試劑之種類有免疫型與化學型兩種。許多研究團隊使用免疫型的試劑來增加檢測之專一性,然而其試劑昂貴、保存較為困難;因此本論文採用成本較低的化學型試劑,但後者在定量與程序上需做精密控制,以提高其精確度,為達此目標,市面上有離心式的微流系統(centrifugal microfluidics),此系統藉由晶片旋轉的離心力克服液體於微流道之毛細力,達到一系列的晶片功能。本研究則在文獻上首次利用重力平衡毛細力的方式製作毛細-重力閥門,進而控制流體的移動。此簡單之方法同時具省能源與在無電力源下亦可操作之優點。 此外,本研究使用壓克力做為晶片,無動件的設計可減少製作成本,並可做為可拋棄式之基材。理論分析影響毛細-重力閥門的參數後,可改變流道的幾何結構,並旋轉晶片至特定的角度,以進行一系列的檢測步驟,誠如定量3.6μL的尿液、分別添加A、B兩種試劑產生催化及呈色反應、混合反應物等功能。再者,肌酸酐濃度是藉由測量混合物於510nm下之光學密度(optical density)變化而得。 本裝置依目前醫檢標準作業之規範,可在二十分鐘完成肌酸酐之檢測步驟,而測試肌酸酐濃度之光學系統也具穩定性,由實際測量不同人體尿液樣本得知,此新方法所測出之結果與醫院量測具有一致性。在未來,此多功能之晶片可再配合尿液白蛋白(albumin)的檢測,以得出白蛋白對肌酸酐的比值(albumin to creatinine ratio),如此即可做為實際居家照護腎功能檢測之用。 The prevalence of chronic kidney disease (CKD) has become an important issue in Taiwan. This is mainly due to the lack of prevention awareness, which may lead to critical delays in treatment. Point-of-care testing (POCT) allows for diagnostic testing near the site of the patients, and may avoid the need for hemodialysis. Therefore, it is necessary to develop a POCT device to evaluate the renal function. Creatinine is a chemical found in steady levels in humans, so the concentration in blood and urine is a standard to evaluate the renal function. Since blood is not easily obtained in point-of-care testing, we aim to quantitatively measure the concentration of urinary creatinine. This can be done by integrating the process of biochemical analysis in the hospital onto a small device based on the concept of “lab-on-a chip”. Though the concentration of creatinine fluctuates with the volume of urine, other analyses such as albumin assay can be measured as well to determine the renal function. There has been much research using expensive immunoassay to enhance the specificity of the biochemical analysis. To lower the cost of the analysis, chemical reagents were used instead. Since we aim to quantitatively measure urinary creatinine, metering and sequential steps on chip are required to increase the precision of the chemical assay. Centrifugal microfluidics is considered one of the most commonly used platform for lab-on-a-chip. It allows a serial process to perform on a plastic substrate without complex fabrication. In this research, we applied a novel and simple approach to control the liquid on the microfluidic chip. Gravitational force, instead of centrifugal force, is used to overcome the capillary force generated at the capillary valve. This valve is called the “capillary-gravitational valve”. There has been, however, no research focusing on integrating the serial process of detecting urinary creatinine onto a microfluidic system by such an approach. And this simple method is power-saving, and can be operated without electricity. Furthermore, PMMA was used as the substrate to reach disposability. No external components were mounted onto the chip, reducing the time and the cost of fabrication. By analyzing the parameters of the capillary-gravitational valve and altering the geometry of the microchannels, metering, adding catalytic and colorimetric reagents sequentially, and mixing could be done by simply rotating the chip to certain angles. The concentration of creatinine was determined by measuring the change of optical density at 510 nm. The optical system was calibrated by first measuring the optical density corresponding to different concentrations of the red dye. The calibration curve shows good linearity. The on-chip creatinine assay was also compared with the creatinine assay processed by the standard in-lab method. Good consistency of the two results indicates the feasibility of the approach we proposed. The serial functions were demonstrated by this device and the process was performed within 20 minutes according to the standard process performed in the hospital. Real urine samples from different people were measured and compared with clinical methods, showing high consistency. This novel approach can be further incorporated with the detection of albumin to derive the urine albumin to creatinine ratio (ACr). In this case, the device can be used to the real time determination of renal function for point-of-care use in practice. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/47608 |
全文授權: | 有償授權 |
顯示於系所單位: | 應用力學研究所 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-100-1.pdf 目前未授權公開取用 | 3.43 MB | Adobe PDF |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。