腎結石是一個全球性的問題，其患者的成長速度極為快速，在醫療方面已造成十 分沉重的負擔。會造成患者成長如此快速的原因之一是因為在結石初期的症狀並不明 顯，無症狀的病人常常忽略問題的嚴重性，許多患者因無病識感，最終導致病情惡化。 在判斷是否為腎結石病患的高風險族群當中，尿液中的鈣離子是極為重要的指標之一， 因為它會與草酸根離子或是磷酸根離子結合形成最常見的鈣質腎結石，因此若能縮短 檢測時間，提早發現異常，配合醫生建議，適時調整飲食及生活作息，就能保障自身 健康。
在本研究中，使用紫尿酸胺與鈣離子反應產生顏色變化的方式，搭配開發微流體 紙基系統的晶片結合垂直過濾的方式，對鈣離子進行比色法的檢測。藉由 RGB 數值 推導出鈣離子濃度。所提出的方法有效使用於鈣離子樣品檢測，濃度區間為 2.2 mg/dL 至 40 mg/dL。由實驗結果可知，使用所開發的微流體紙基晶片系統，應用於鈣離子檢 測中可得到線性度 R2 高達 0.99 以上，並與國立成功大學腎臟科合作，採集真實病患 檢體，比較紙基晶片系統與成大醫院的數值，在 28 個檢體個案中回收率平均可達 99%。 由此結果得出，本文所提出的鈣離子檢測系統不僅降低檢測成本、簡化製程步驟、操 作簡易，且為十分可靠的方法。

Kidney stones are a global problem, and their patients are growing at an extremely fast rate, causing a heavy burden on medical care. Among the high-risk groups to determine whether it is a kidney stone patient, calcium ion in urine is one of the extremely important indicators, because it combines with oxalate ion or phosphate ion to form the most common calcium kidney stones.
In this study, the colorimetric detection of calcium ions was carried out by using Murexide reacting with calcium ions to produce color changes, in combination with the development of a microfluidic paper-based system chip combined with vertical filtration. The calcium ion concentration is derived from the RGB values. The proposed method was effectively used for calcium ion sample detection in the concentration range from 2.2 mg/dL to 40 mg/dL. In cooperation with the NCKUH, actual patient samples were collected, and the paper-based chip system was compared with the values of NCKUH. According to the data of the chip system and the NCKUH, the recovery rate of the 28 specimens can reach an average of 99%. We also detect the calcium ion in artificial urine. The result of detection can reach an average of 101%. From the results, the calcium ion detection system in this paper not only reduces the detection cost, simplifies the process steps, and is easy to operate, but also a very reliable method.

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