Sensitive detection of fractalkine based on AuNPs and metal-organic frameworks composite at para-sulfonatocalix[4]arene-AuNPs assembled multilayer interface

Fractalkine (FKN) has been claimed as a predictive biomarker of Barrett's Esophagus for the first time recently, whereas there are few methods for quantitative detection of FKN. In order to develop a sensitively electrochemical biosensor of FKN, pSC4-AuNPs self-assembled multilayer film on the gold electrode surface was utilized to immobilize anti-FKN as a biorecognition surface. A novel porous para-sulfonatocalix[4]arene-coated gold nanoparticles-functionalized metal-organic frameworks (pSC4-AuNPs/Cu-MOFs) was fabricated to recognize FKN by FKN aptamer and as signal tags for H2O2 catalysis. pSC4-AuNPs multilayer displayed good biocompatibility and high electronic transmission. Combing with the good catalysis ability of Cu-MOFs, the quantitative FKN detection was achieved by the sensitive electrochemical immunosensor with the detection limit of 7.4 pg/mL. With this design, the signal amplification strategy of the pSC4-AuNPs/Cu-MOFs composite offers a potential application of clinical detection of FKN.