Dendritic quinary PtRhMoCoFe high-entropy alloy as a robust immunosensing nanoplatform for ultrasensitive detection of biomarker.

Recently, high-entropy alloys have superior physicochemical properties as compared to conventional alloys for their glamorous "cocktail effect". Nevertheless, they are scarcely applied to electrochemical immunoassays until now. Herein, uniform PtRhMoCoFe high-entropy alloyed nanodendrites (HEANDs) were synthesized by a wet-chemical co-reduction method, where glucose and oleylamine behaved as the co-reducing agents.

Ultrasensitive sandwich-typed electrochemical immunoassay for detection of squamous cell carcinoma antigen based on highly branched PtCo nanocrystals and dendritic mesoporous SiO@AuPt nanoparticles.

Squamous cell carcinoma antigen (SCCA) is one of the common squamous cell carcinomas (SCC) in women, which usually works as a tumor biomarker for cervical cancer in diagnostic applications. Herein, bimetallic PtCo highly branched nanocrystals (PtCo BNCs) acted as electrode substrates to construct sandwich-typed electrochemical immunosensor for ultrasensitive detection of SCCA, by using dendritic mesoporous SiO@AuPt nanoparticles (DM-SiO@AuPt NPs) to adsorb electroactive thionine (Thi) as a signal label. The PtCo BNCs enlarged the loading of the primary antibody (Ab), showing effective improvement in conductivity and sensitivity.

Theoretical investigation of N-nitrosodimethylamine formation from dimethylamine nitrosation catalyzed by carbonyl compounds.

The carbonyl-compound-catalyzed nitrosation of amines to form carcinogenic nitrosamines under nonacidic condition is different from the classic nitrosation via acidification of nitrite anion. The mechanistic pathways of N-nitrosodimethylamine (NDMA) formation by the reactions of dimethylamine (DMA) with the nitrite anion catalyzed by carbonyl compounds have been investigated using the DFT/B3LYP method at the 6-311+G(d,p) level. The computational results show that the energy barriers of the nucleophilic addition reaction, which were calculated as 27-40 kcal/mol, increase significantly with methylation but vary slightly with chloromethylation on the carbonyl group.

Theoretical investigation of nitration and nitrosation of dimethylamine by N2O4.

Reactive nitrogen oxygen species (RNOS) contribute to the deleterious effects attributed to reacting with biomolecules. The mechanisms of the nitration and nitrosation of dimethylamine (DMA), which is the simplest secondary amine by N2O4, a member of RNOS, have been investigated at the CBS-QB3 level of theory. The nitration and nitrosation proceed via different pathways.