Ratiometric fluorescent Si-FITC nanoprobe for immunoassay of SARS-CoV-2 nucleocapsid protein  

作　　者：Guobin Mao Silu Ye Wen Yin Yang Yang Xinghu Ji Jin He Yingxia Liu Junbiao Dai Zhike He Yingxin Ma 

机构地区：[1]CAS Key Laboratory of Quantitative Engineering Biology,Guangdong Provincial Key Laboratory of Synthetic Genomics and Shenzhen Key Laboratory of Synthetic Genomics,Shenzhen Institute of Synthetic Biology,Shenzhen Institutes of Advanced Technology,Chinese Academy of Sciences,Shenzhen 518055,China [2]State Key Laboratory of Agricultural Microbiology,College of Life Science and Technology,Huazhong Agricultural University,Wuhan 430070,China [3]Shenzhen Key Laboratory of Pathogen and Immunity,National Clinical Research Center for Infectious Disease,State Key Discipline of Infectious Disease,Shenzhen Third People's Hospital,Second Hospital Affiliated to Southern University of Science and Technology,Shenzhen 518112,China [4]College of Chemistry and Molecular Sciences,Wuhan University,Wuhan 430072,China

出　　处：《Nano Research》2023年第2期2859-2865,共7页纳米研究（英文版）

基　　金：supported by the National Key Research and Development Program of China(No.2021YFA0910900);the Sino-German rapid response funding call for COVID-19 related research(No.C-0008);the National Natural Science Foundation of China(Nos.32222044 and 22104147);Shenzhen Municipal Science and Technology Innovation Council(No.RCYX20210609103823046);Youth Innovation Promotion Association CAS(No.2021359);Natural Science Foundation of Guangdong(Nos.2018B030306046 amd 2020A1515111130);Guangdong Provincial Key Laboratory of Synthetic Genomics(No.2019B030301006);Shenzhen Science and Technology Program(No.KQTD20180413181837372);Shenzhen Outstanding Talents Training Fund.

摘　　要：Coronavirus disease 2019(COVID-19)highlights the importance of rapid and reliable diagnostic assays for the management of virus transmission.Here,we developed a one-pot hydrothermal method to prepare Si-FITC nanoparticles(NPs)for the fluorescent immunoassay of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)nucleocapsid protein(N protein).The synthesis of Si-FITC NPs did not need post-modification,which addressed the issue of quantum yield reduction during the coupling reaction.Si-FITC NPs showed two distinct peaks,Si fluorescence atλem=385 nm and FITC fluorescence atλem=490 nm.In the presence of KMnO_(4),Si fluorescence was decreased and FITC fluorescence was enhanced.Briefly,in the presence of N protein,catalase(CAT)-linked secondary antibody/reporter antibody/N protein/capture antibody immunocomplexes were formed on microplates.Subsequently,hydrogen peroxide(H_(2)O_(2))and Si-FITC NPs/KMnO_(4)were injected into the microplate together.The decomposition of H_(2)O_(2)by CAT resulted in remaining of KMnO_(4),which changed the fluorescence intensity ratio of Si-FITC NPs.The fluorescence intensity ratio correlated significantly with the N protein concentration ranging from 0.02 to 50.00 ng/mL,and the detection limit was 0.003 ng/mL,which was more sensitive than the commercial ELISA kit with a detection limit of 0.057 ng/mL.The N protein concentration can be accurately determined in human serum.Furthermore,the COVID-19 and non-COVID-19 patients were distinguishable by this method.Therefore,the ratiometric fluorescent immunoassay can be used for SARS-CoV-2 infection diagnosis with a high sensitivity and selectivity.

关 键 词：Si-FITC nanoparticles ratiometric fluorescent probe SARS-CoV-2 ELISA 

分 类 号：O62[理学—有机化学]