Copper nanocluster-based fluorescence enhanced determination of d-penicillamine.

Taking advantage of the compelling properties of d-penicillamine (d-PA) combined with copper, a method for the sensitive and selective determination of d-PA was established using copper nanocluster (Cu NC)-based fluorescence enhancement. d-PA molecules containing a thiol compound showed a strong tendency to combine with the surface of Cu NCs, causing the re-dispersion of nanoclusters and therefore fluorescence intensity was enhanced. Fluorescence enhancement efficiency of Cu NCs induced by d-PA was linear, with the d-PA concentration varying from 0.6-30 µg ml-1 (R2  = 0.9952) and with a detection limit of 0.54 µg ml-1 . d-PA content in human urine samples was detected with recoveries of 104.8-112.99%. Fluorescence-enhanced determination of d-PA using Cu NCs was established for the first time and this rapid, easy and sensitive method should attract much attention for this application.

Fabrication and Photocatalytic Activity of Ag3PO4/T-ZnOw Heterostructures.

The Ag3PO4/tetrapod-like ZnO whisker (T-ZnOw) heterostructures were prepared via a simple precipitation method. The obtained heterostructures were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-Vis diffuse reflectance spectroscopy. The photodegradation activity of Ag3PO4/T-ZnOw was evaluated by the degradation of Rhodamine B (RhB) under visible light irradiation. When the molar ratio of Ag3PO4 to T-ZnOw was 10% (Ag3PO4/T-ZnOw-2), the highest degradation efficiency (92.9%) could be achieved among the heterostructures. The photodegradation rate constant of Ag3PO4/T-ZnOw-2 (0.05179 min-1) was 3.59 times that of T-ZnOw (0.01444 min-1). Besides, the Ag3PO4/T-ZnOw-2 photocatalyst still possessed a degradation efficiency of 77.8% after four successive cycles. The Ag3PO4/T-ZnOw-2 catalyst had much higher photocatalytic activity than pure T-ZnOw and better stability and reusability than pure Ag3PO4. The effect of different scavengers on degradation efficiency was investigated, and the possible photocatalytic mechanism of the Ag3PO4/T-ZnOw photocatalyst was also put forward.

Eggshell Membrane-Templated MnO2 Nanoparticles: Facile Synthesis and Tetracycline Hydrochloride Decontamination.

Taking advantages of reticular proteins and reductive groups on the surface, eggshell membrane (ESM) was selected to synthesize MnO2 nanoparticles from potassium permanganate through a super simple way in which ESM acted as both template and reductant. This process avoided harsh reaction conditions or complicated aftertreatments and thus owned the merits of green synthesis, handy operation, low cost, and easy purification. The ESM-templated MnO2 nanoparticles (MnO2 NPs/ESM) were characterized, and the content of nanomaterials on the template was tested. MnO2 NPs/ESM showed a good capacity for decontamination of tetracycline hydrochloride (TCH). The macroscopical materials can be separated easily by taking the membrane out to stop the degradation instead of centrifugation or filtration. It was studied that 72.27% of TCH (50 mg/L) was decontaminated in 20 min by 0.1920 g/L MnO2 nanoparticles, and removal efficiency could reach 83.10% after 60 min under buffered condition. The kinetics was studied with or without buffer, and it was concluded that the degradation process followed a pseudo-second-order model. The facile synthesis of materials and effective degradation would facilitate the nano-MnO2-based decontamination applications.