A nanoplatform-based aptasensor to electrochemically detect epinephrine produced by living cells.

A novel aptasensor has been designed for quantitative monitoring of epinephrine (EP) based on cerium metal-organic framework (CeMOF) loaded gold nanoparticles (AuNPs). The aptamer, specific to EP, is immobilized on a flexible screen-printed electrode modified with AuNPs@CeMOF, enabling highly selective binding to the target biomolecule. Under optimized operational conditions, the peak currents using voltammetric detection measured at voltage of 83 mV (vs. Ag/AgCl) for epinephrine exhibit a linear increase within concentration in the range 1 pM-10 nM. Following this detection strategy, a boasted limit of detection of 0.3 pM was achieved, surpassing the sensitivity of most reported methods. The developed biosensor showcased exceptional performance in detection of EP in spiked serum sample, with remarkable recovery range of  95.8-113% and precision reflected by low relative standard deviation (RSD) ranging from 2.23 to 6.19%. These results indicate the potential utility of this biosensor as a valuable clinical diagnostic tool. Furthermore, in vitro experiments were carried out using the presented biosensor to monitor the release of epinephrine from PC12 cells upon extracellular stimulation with K+ ions.

CdS/Ti3C2 heterostructure-based photoelectrochemical platform for sensitive and selective detection of trace amount of Cu2.

Photoelectrochemical (PEC) detection as a potential development strategy for Cu2+ ion sensor has arisen extensive attention. Herein, CdS/Ti3C2 heterostructure was synthesized by electrostatically driven assembly and hydrothermal method. On the basis of a CdS/Ti3C2 heterostructure, a novel anodic PEC sensing platform was constructed for highly sensitive detection of trace amount of Cu2+. Carrier transport at the interface of CdS/Ti3C2 heterostructure was tremendously improved, due to the generation of effective Schottky junctions. Under visible light irradiation, the CdS/Ti3C2 heterostructure-modified PEC platform exhibits great anode photocurrent signal, and the formation of CuxS reduces the PEC response with the presence of Cu2+ as a representative analyte. Thus, the linear response of Cu2+ ranges from 0.1 nM to 10 µM and the limits of detection (LOD, 0.05 nM) are obtained, which is lower than that of WHO's Guidelines for Drinking-water Quality (30 µM). This idea of component reconstitution provides a new paradigm for the design of advanced PEC sensors.

N-(2,4-Dichloro-phen-yl)-1,3-thia-zol-2-amine.

In the title mol-ecule, C(9)H(6)Cl(2)N(2)S, the mean planes of the benzene and thia-zole rings make a dihedral angle of 54.18 (8)°. In the crystal, mol-ecules are joined into dimers with an R(2) (2)(8) ring motif by pairs of N-H⋯N hydrogen bonds. These dimers are linked by C-H⋯Cl inter-actions into layers parallel to (011). The thia-zole rings form columns along the c-axis direction, with a centroid-centroid separation of 3.8581 (9) Å, indicating π-π inter-actions. An intra-molecular C-H⋯S contact also occurs.