光电化学生物传感器用于测定丁草胺

Application of Photoelectrochemical Biosensor to Determination of Butachlor

制备了ITO/Gr/CH3NH3PbI3/CS/GOx电极,将制得的电极浸入5.0mL的0.1mol·L^-1 PBS(pH 7.0)中,加入丁草胺标准溶液,保持10min,然后将电极取出插入含有0.8mmol·L^-1葡萄糖的0.1mol·L^-1 PBS(pH 7.0)中,测量光电流(I)。另做空白试验(操作同上,但不存在丁草胺),测量光电流(I0)。由(I0-I)/I0×100计算丁草胺对光电流的抑制率。结果表明,抑制率与丁草胺的浓度在0.02~10.0nmol·L^-1内呈线性关系,检出限(3S/N)为0.005nmol·L^-1。方法用于测定蔬菜和水果空白加标样品中的丁草胺,测定值与气相色谱-质谱法的测定结果一致,测定值的相对标准偏差(n=6)在1.8%~4.7%之间,加标回收率在93.3%~102%之间。

The electrode of ITO/Gr/CH3 NH3 PbI3/CS/GOx was prepared.The obtained electrode was immersed into 5.0 mL of 0.1 mol·L^-1 PBS(pH 7.0),and butachlor solution was added.After keeping for 10 min,the electrode was taken out and immersed into 0.1 mol·L^-1 PBS(pH 7.0)containing 0.8 mmol·L^-1 gluocose,and the photoelectric current(I)was measured.A blank test was done in the same way as mentioned above but in absence of butachlor,and the photoelectric current(I0)was measured.Inhibition rate of photoelectric current by butachlor was calculated from(I0-I)/I0×100.The results showed that inhibition rate was linear with the concentration of butachlor in the range of 0.02^-10.0 nmol·L^-1,and the detection limit(3 S/N)was 0.005 nmol·L^-1.The method was applied to determination of butachlor in spiked blank samples of vegetables and fruits,giving measured values consistent with those obtained by gas chromatography-mass spectrometry,and RSDs(n=6)between 1.8% and 4.7%.Recovery obtained by standard addition method were in the range of 93.3%^-102%.