Rapid photothermal assay for ultrasensitive point-of-care detection of tumor markers based on a filter membrane.

An ultrasensitive photothermal assay was designed for point-of-care testing (POCT) of tumor markers based on a filter membrane. Firstly, CuSe was successfully encapsulated in liposome spheres with biotin on the surface and connected to carcinoembryonic antigen (CEA) aptamer with 3'end modified biotin by streptavidin. Secondly, the CEA antibody was successfully modified on the surface of the nitrocellulose membrane through simple incubation.

Gas-Mediated Immunoassay for the Carcinoembryonic Antigen at Atmospheric Pressure with Smartphone Coupling with the Fluorescence Quenching Length of Perovskite Capillary.

By combining the photothermal properties of the 3,3',5,5'-tetramethylbenzidine oxidation product (TMBox) with the sensitive quenching of perovskite fluorescence by ammonia gas, a gas-mediated immunoassay at atmospheric pressure was constructed, which took the fluorescence quenching length of perovskite fluorescent capillary as the signal output. First, a CsPbBr perovskite with surface modification of 3-aminopropyl triethoxysilane was synthesized by thermal injection and decorated to the capillary wall by glutaraldehyde cross-linking. In the presence of HO and the tumor marker carcinoembryonic antigen (CEA), TMB was oxidized to TMBox by the horseradish peroxidase (HRP)-labeled CEA antibody.

Multicolor and photothermal dual-mode assay of alkaline phosphatase based on the UV light-assisted etching of gold nanorods.

A multicolor and photothermal dual-mode assay for sensitive alkaline phosphatase (ALP) determination was realized based on the 3,3',5,5'-tetramethylbenzidine (TMB)-induced etching of gold nanorods (AuNRs). TMB was oxidized under ultraviolet light irradiation to form TMB. In the presence of ALP, ascorbic acid phosphate (AAP) is converted to ascorbic acid, which can then reduce the levels of TMB, resulting in lower concentrations of TMB.

Accelerating the peroxidase-like activity of MoSe nanosheets at physiological pH by dextran modification.

Surface modification of MoSe2via dextran during ultrasound exfoliation is demonstrated to be an efficient and easy strategy to accelerate the peroxidase-like catalytic activity of MoSe2 nanosheets at neutral pH. The enhancement of catalytic activity is owing to the rich negative charges of dextran on the dextran-modified MoSe2 nanosheets.