Ultrasensitive photoelectrochemical immunosensor for carcinoembryonic antigen detection based on pillar[5]arene-functionalized Au nanoparticles and hollow PANI hybrid BiOBr heterojunction.

In this study, an ultrasensitive and specific photoelectrochemical (PEC) immunosensor was designed for carcinoembryonic antigen (CEA) detection. Benefitting from the ascorbic acid (AA) used as an electron donor that led to a notable change in the photocurrent density, pillar[5]arene functionalized Au and Polyaniline-Bismuth oxybromide heterojunction (Au@WP5/PANI-BiOBr) displayed superior PEC performance for CEA sensing. In detail, the localized surface plasmon resonance (LSPR) of the Au NPs and host-guest complexation between WP5 and AA increased the photocurrent signal, the photogenerated holes on BiOBr accelerated the oxidation of AA, and the fast electron transfer of the hollow PANI tubes benefited an increase in the photocurrent. The antibody effectively bound with CEA when bovine serum albumin blocked the residual sites on the Au@WP5/PANI-BiOBr electrode, generating a clear decrease in photocurrent density in AA solution. Under the optimum condition, the developed PEC immunosensor exhibited a sensitive response to CEA which was linear in the range of 0.01 ng mL-1 to 50 ng mL-1 with a detection limit of 3 pg mL-1. The proposed PEC immunosensor displayed high specificity, good stability, and excellent reproducibility, paving a new way to construct sensitive and specific photoactive heterojunction materials for biomarker immunosensing.

GOx-assisted synthesis of pillar[5]arene based supramolecular polymeric nanoparticles for targeted/synergistic chemo-chemodynamic cancer therapy.

BACKGROUND: Cancer is the most serious world's health problems on the global level and various strategies have been developed for cancer therapy. Pillar[5]arene-based supramolecular therapeutic nano-platform (SP/GOx NPs) was constructed successfully via orthogonal dynamic covalent bonds and intermolecular H-bonds with the assistance of glucose oxidase (GOx) and exhibited efficient targeted/synergistic chemo-chemodynamic cancer therapy. METHODS: The morphology of SP/GOx NPs was characterized by DLS, TEM, SEM and EDS mapping. The cancer therapy efficinecy was investigated both in vivo and in vitro. RESULTS: SP/GOx NPs can load drug molecules (Dox) and modify target molecule (FA-Py) on its surface conveniently. When the resultant FA-Py/SP/GOx/Dox NPs enters blood circulation, FA-Py will target it to cancer cells efficiently, where GOx can catalyst the overexpressed glucose to generate H2O2. Subsequently, the generated H2O2 in cancer cells catalyzed by ferrocene unit to form •OH, which can kill cancer cells. Furthermore, the loaded Dox molecules released under acid microenvironment, which can further achieve chemo-therapy. CONCLUSION: All the experiments showed that the excellent antitumor performance of FA-Py/SP/GOx/Dox NPs, which provided an new method for pillar[5]arene-based supramolecular polymer for biomedical applications.