Application Of Chemically Modified Nanopores In The Detection Of Diabetes

Due to the change of lifestyle in modern society,the improvement of living standard and the aggravation of aging population,the incidence of diabetes has been increasing year by year,which has become a serious threat to human health in modern society.The complete cure for diabetes hasn't been found,and the main treatment for diabetes is to reduce the harm of the disease by controlling the blood sugar level.Blood glucose and glycated hemoglobin(HbA1c)are two important indicators of diabetes,and their detection can provide effective basis for the formulation of the treatment plan.Nanopore sensing is a kind of non-labeled detection technology with high sensitivity and high throughput,while solid nanopore has been widely developed in biosensor development due to its high stability,steerable size and adjustable inner surface.In this paper,diversified modification schemes based on boronic acid were designed for conical solid nanopores,and the highly sensitive detection of glucose and HbA1c was realized by using these modified nanopores.1.Application of boronic acid-based composite nanopores in glucose detection In this study,we designed the two kinds of composite nanopores.One is a composite nanopore manufactured by the incorporation of polyvinyl alcohol(PVA)hydrogel into the nanopore modified by boronic acid.The competition between glucose and PVA for binding to the boronic acid groups on the inner wall results in the enhancement of the rectification effect and thus this nanopore can be applied to glucose detection;The second is a composite nanopore fabricated by the deposition of poly(aminobenzylboric acid)on a PET film outside the tip side.The combination of the boronic acid groups of the polymer and glucose under alkaline conditions would enhance the rectification effect of the nanopore and realize the detection of glucose.The introduction of the boronic acid groups can circumvent the stability defect of traditional enzymic glucose biosensors and can be applied to the development of novel glucose biosensors.2.Study on the application of boronic acid-modified nanopore to the detection of HbA1c.In this study,we develop a current-blocking-pulse biosensor based on a nanopore modified by boronic acid groups,which can be successfully applied to the efficient recognition of HbA1c molecules.By optimizing the p H value and applying voltage of the system,the HbA1c molecules would translocate through the nanopore,generating characteristic currentblocking-pulse signals,which can effectively reflect the relevant information of protein molecules and realize the sensitive recognition of HbA1c.The addition of hemoglobin would not cause current change and affect the translocation of HbA1c.This biosensor possesses the advantages of convenient production,simple operation,and superior analyzing performance,providing a novel idea for the development of point-of-care testing biosensors for HbA1c.