本文選題：玄參　切入點：哈巴俄苷　出處：《分析化學(xué)》2017年05期 　論文類型：期刊論文

【摘要】：在不同溫度及模擬血液pH值條件下,采用熒光光譜法和紫外-可見吸收光譜法研究了哈巴俄苷(Harpagoside,HAR)與人血清白蛋白(Human serum albumin,HSA)的結(jié)合反應(yīng)。結(jié)果表明,HAR有規(guī)律地使HSA內(nèi)源熒光猝滅,猝滅常數(shù)隨溫度升高而降低,其猝滅機(jī)制為兩者形成復(fù)合物而引起的的靜態(tài)猝滅;不同條件下兩者結(jié)合常數(shù)K_A均大于10~5L/mol,結(jié)合位點數(shù)n≈1。由Van't Hoff方程計算獲得了不同條件下HAR與HSA相互作用的熱力學(xué)參數(shù),由ΔG、ΔH和ΔS均小于0可知,兩者結(jié)合的主要作用力是氫鍵和范德華力,且兩者結(jié)合是吉布斯自由能降低的自發(fā)過程。根據(jù)F銉rster非輻射轉(zhuǎn)移理論計,計算了不同條件下HAR與HSA的結(jié)合距離r在4.01~4.28 nm范圍內(nèi),表明兩者結(jié)合過程發(fā)生了非輻射能量轉(zhuǎn)移。同步熒光光譜表征結(jié)果表明,HAR使HSA的色氨酸和酪氨酸殘基所處的微環(huán)境極性增強(qiáng),疏水性減弱,導(dǎo)致HSA構(gòu)象發(fā)生了一定程度的改變。
[Abstract]:Under different temperature and simulated blood pH value, the binding reaction of Harpagoside HARs with human serum albumin (HSA) was studied by fluorescence spectrometry and UV-Vis absorption spectrometry. The results showed that Har regularly quenched the endogenous fluorescence of HSA. The quenching constant decreases with the increase of temperature, and the quenching mechanism is the static quenching caused by the formation of complex between the two. Under different conditions, the binding constant K _ s _ A is greater than 10 ~ 5L / mol, and the binding site number n 鈮，

本文編號：1649996