Study On Portable AGFET Biosensor For Detection Of Serum CK-MB

Acute myocardial infarction(AMI)is one of the major life-threatening diseases in the world,with high morbidity and mortality.Biomarkers are a kind of measurable and quantified physiological parameters,which are often used as an important reference index for disease diagnosis,disease status evaluation and treatment level monitoring.Serum Creatine kinase MB(CK-MB)is one of the main biomarkers related to the diagnosis of AMI.Currently,the diagnosis of AMI requires on-site sampling,long Sample testing procedure and expensive hospitalization costs while the onset of AMI is rapid and often endangers the life of the patients.Therefore,rapid diagnosis of AMI is needed to ensure the safety of patients.As a sensing module with high detection specificity,high sensitivity and low requirements for supporting equipment,the aptameric graphene field effects transistor(AGFET)offers a idea about solving this difficult problem.In this paper,the sensing mechanism of AGFET is briefly analyzed and the mathematical model of its response signal and CK-MB concentration is established.the processing of the planar electrode of the module and the transfer of graphene were completed;Raman spectroscopy,energy spectrometer and electrical measurement were used to characterize the graphene before and after modification.Experiments were designed to test the CK-MB detection ability of the AGFET sensing module.AGFET based on PEI isolation layer was used to detect CK-MB in serum.Through the experiment,a better modifier concentration of PEI was obtained.PEI isolation layer weakened the effect of adsorption of other molecules in serum on graphene electrical signals.The stability of AGFET for the detection of CK-MB in serum was improved,and The specificity of AGFET was studied experimentally.The design of AGFET detection system is Completed,including A/D,D/A and human-computer interaction module circuit designing,the circuit programming completed by MDK development tool,FreeRTOS multi-task real-time system and Emwin graphics library.The measuring range,signal response time and precision of the portable AGFET sensing device for detecting serum CK-MB concentration were studied.A CK-MB AGFET sensing module was studied to detect CK-MB in serum in this paper.PEI isolation layer was constructed on the graphene surface of the module to improve the detection stability of CK-MB in serum.A sensing device be comprised of sensing module and its detection system was constructed to realize the rapid detection of CK-MB in serum,which provided an effective way for the early diagnosis of AMI.