基于GOD@Fe3O4@SiO2-NH2-CDI NPs构建葡萄糖生物传感器OA

To address the issues of poor stability,high equipment cost,and complex operational procedures in current glucose concentration detection methods,a surface functionalization modification approach was adopted.The effects of acetic acid,3-aminopropyltriethoxysilane(APTES),and N,N'-carbonyldiimidazole(CDI)on the modification of magnetic nanoparticles were investigated using conductivity measurements,Fourier transform infrared spectroscopy(FTIR)and Bradford enzyme loading assays.A novel enzyme carrier material,Fe3O4@SiO2-NH2-CDI NPs,was successfully prepared.This material was then integrated with an SBA-40E sensor to construct a novel biosensor for glucose concentration detection.Electrochemical detection was performed,and the performance was compared in parallel with conventional biosensors for validation.The results showed that the Fe3O4@SiO2-NH2-CDI NPs exhibited an enzyme loading capacity of 116 mg/g,which was 7.73 times higher than that of Fe3O4@SiO2 NPs.The GOD@Fe3O4@SiO2-NH2-CDI NPs biosensor demonstrated a linear response range for glucose detection of 0.25-1.25 mM(R2≥0.994),maintained excellent linearity after 25 d of storage,with a detection limit of 0.054 mM and a sensitivity of 58.9 μA·L/(mol·cm2).The relative standard deviations(RSD)for standard sample detection over 15 d were all less than or equal to 5.0%.For glucose beverage detection,the RSD ranged from 0.90%to 2.30%,outperforming conventional GOD biosensors(which showed RSD of 2.20%to 3.20%)in terms of detection stability and accuracy.The service life of the developed biosensor was 1.79 to 3.13 times longer than that of other sensors(8-14 d),and the detection limit was reduced by 49.3%to 80.0%compared to most similar sensors.This research provides a reference for the development of biosensors towards greater efficiency,accuracy and convenience.