測定血液中葡萄糖的濃度有什麼方法?

Question

這是我們酵素學期未考的題目之一

題目為：

一、請設計兩種方法測定血液中葡萄糖的濃度，並說明：

(1)如何計算測定的葡萄糖濃度

(2)該方法為 end point method 或 kinetic method，為什麼 ?

(3)該方法為 preceding reaction 或 succeeding reaction，為什麼?

(4)反應式為 auxiliary reaction 或 indicator reaction，為什麼?


二、請設計一個實驗測定樣品中 metabolite intermediate 的濃度，以

tetrazolium salt 為指示劑，您也可以以血液中的葡萄糖為例




當然啦，我也知道來這裡發問不太好，這樣就變得很懶惰，而且也不一定會有回答，不過還是來這裡問問，希望能有一些參考資料

Answer 1

(1)除了Lipoprotein是用電泳分析再用濃度掃瞄測定儀測濃度，其餘均用分光光度測量法(spectrophtometry)測定濃度。
(2)動力學方法(Kinetic method)
動力學方法主要是利用光學密度對時間的變動率測量最終的結果，測定的血漿先與酵素培育，之後加入特定的受質與酵素反應，結果分析物的濃度會與光學密度成正比或是反比，儀器報告的單位為OD/min
終點測定法(End Point Method)
這種方法的受質反應最後會受到醋酸的終止，光學密度的變化與受測物質的同度成正比
(3)當第一次實驗或觀測的結果不能證實假設時，有時用一種能起澄清作用的 輔助假設 (auxiliary hypothesis) 來適應矛盾的事實，而不是一股腦地拋棄原來的假設。這種修正的過程可一直進行下去，直至主要假設附加了一大堆特設條件。
Strain CHR63 is a salt-sensitive mutant of the moderately halophilic wild-type strain Halomonas elongata DSM 3043 that is affected in the ectoine synthase gene (ectC). This strain accumulates large amounts of Nγ-acetyldiaminobutyrate (NADA), the precursor of ectoine (D. Cnovas, C. Vargas, F. Iglesias-Guerra, L. N. Csonka, D. Rhodes, A. Ventosa, and J. J. Nieto, J. Biol. Chem. 272:25794–25801, 1997). Hydroxyectoine, ectoine, and glucosylglycerate were also identified by nuclear magnetic resonance (NMR) as cytoplasmic organic solutes in this mutant. Accumulation of NADA, hydroxyectoine, and ectoine was osmoregulated, whereas the levels of glucosylglycerate decreased at higher salinities. The effect of the growth stage on the accumulation of solutes was also investigated. NADA was purified from strain CHR63 and was shown to protect the thermolabile enzyme rabbit muscle lactate dehydrogenase against thermal inactivation. The stabilizing effect of NADA was greater than the stabilizing effect of ectoine or potassium diaminobutyrate. A 1H NMR analysis of the solutes accumulated by the wild-type strain and mutants CHR62 (ectA::Tn1732) and CHR63 (ectC::Tn1732) indicated that H. elongata can synthesize hydroxyectoine by two different pathways—directly from ectoine or via an alternative pathway that converts NADA into hydroxyectoine without the involvement of ectoine.