一种具有级联酶促活性金属—有机框架材料的制备及尿酸比色法检测研究

Preparation of metal-organic framework with enzymatic cascade reaction activity for colorimetric detection of uric acid

目的:制备一种具有级联酶催化活性的功能化金属—有机框架(MOF)材料,并将其用于体液中尿酸浓度的比色法测定。方法:以1,3,5-苯三甲酸(BTC)和氯化铁(FeCl3)为原料,在室温下采用一锅合成法包封尿酸氧化酶(UOx),得到UOx@FeBTC。利用扫描电子显微镜、透射电子显微镜、X射线衍射、X-射线光电子能谱、紫外—可见光谱、傅里叶变换红外光谱对制备的材料进行表征,明确其性质并证明尿酸酶的成功包封。对UOx@Fe-BTC的合成时间及pH条件进行优化,考察材料的稳定性及特异性。最后利用3,3’,5,5’-四甲基联苯胺(TMB)进行显色反应,对尿酸浓度进行定量检测。结果:成功制备了具有级联酶促效应的UOx@Fe-BTC MOF材料。pH 3.5时,酶促反应活性最强。在优化的分析条件下,尿酸的线性响应范围为5~800μmol/L(R2=0.9975),检测限为1.1μmol/L;常见内源性物质不干扰测定。结论:具有双酶体系的功能MOF材料,可为尿酸水平的常规监测和临床相关疾病诊断提供了一种新的技术手段。

Objective:To prepare a functional metal-organic framework(MOF)material with enzymatic cascade reaction activity for colorimetric detection of uric acid(UA)concentration in biofluids.Methods:Urate oxidase(UOx)was encapsulated by one-pot synthesis method at room temperature using 1,3,5-benzenetricarboxylic acid(BTC)and FeCl3 as raw materials,so as to obtain UOx@Fe-BTC.Scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffractometer(XRD),X-ray photoelectron spectrometer(XPS),ultraviolet-visible(UV-vis)spectrophotometer,and Fourier transform infrared(FT-IR)spectrometers were used to characterize the prepared materials,identify their properties and validate the effective encapsulation of UOx.The synthesis time and pH conditions of UOx@Fe-BTC were optimized and the stability and specificity of the nanocomposite were investigated.Finally,3,3',5,5'-tetramethylbenzidine(TMB)was used for colorimetric reaction,and the concentration of UAwas quantitatively detected.Results:The UOx@Fe-BTC metal-organic frame material with enzymatic cascade reaction activity was successfully prepared.At pH 3.5,the enzymatic activity was the strongest.Under the optimal condition,a well-defined linear response to UA was obtained in the concentration range of 5-800μmol/L(R2=0.99757),with a limit of detection of 1.1μmol/L.The commonly endogenous substances could not produce interference to UA assay.Conclusion:The functional MOF material with bi-enzyme system can provide a new technical means for UA routine monitoring and the diagnosis of clinical related diseases.