Ultrasensitive Glutathione-Mediated Facile Split-Type Electrochemiluminescence Nanoswitch Sensing Platform.

Seeking for an advanced electrochemiluminescence (ECL) platform is still an active and continuous theme in the ECL-sensing realm. This work outlines a femtomolar-level and highly selective glutathione (GSH) and adenosine triphosphate (ATP) ECL assay strategy using a facile split-type gold nanocluster (AuNC) probe-based ECL platform. The system utilizes GSH as an efficient etching agent to turn on the MnO2/AuNC-based ECL nanoswitch platform. This method successfully achieves an ultrasensitive detection of GSH, which significantly outperformed other sensors. Based on the above excellent results, GSH-related biological assays have been further established by taking ATP as a model. Combined with the high catalytic oxidation ability of DNAzyme, this ECL sensor can realize ATP assay as low as 1.4 fmol without other complicated exonuclease amplification strategies. Thus, we successfully achieved an ultrahigh sensitivity, extremely wide dynamic range, great simplicity, and strong anti-interference detection of ATP. In addition, the actual sample detection for GSH and ATP exhibits satisfactory results. We believe that our proposed high-performance platform will provide more possibilities for the detection of other GSH-related substances and show great prospect in disease diagnosis and biochemical research.

Efficient Removal and Recovery of Ag from Wastewater Using Charged Polystyrene-Polydopamine Nanocoatings and Their Sustainable Catalytic Application in 4-Nitrophenol Reduction.

This study addresses the long-standing challenges of removing and recovering trace silver (Ag) ions from wastewater while promoting their sustainable catalysis utilization. We innovatively developed a composite material by combining charged sulfonated polystyrene (PS) with a PDA coating. This composite serves a dual purpose: effectively removing and recovering trace Ag+ from wastewater and enabling reused Ag for sustainable applications, particularly in the catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The PS-PDA demonstrated exceptional selectivity to trace Ag+ recycling, which is equal to 14 times greater than the commercial ion exchanger. We emphasize the distinct roles of different charged functional groups in Ag+ removal and catalytic reduction performance. The negatively charged SO3H groups exhibited the remarkable ability to rapidly enrich trace Ag ions from wastewater, with a capacity 2-3 times higher than that of positively-N+(CH3)3Cl and netural-CH2Cl-modified composites; this resulted in an impressive 96% conversion of 4-NP to 4-AP within just 25 min. The fixed-bed application further confirmed the effective treatment capacity of approximately 4400 L of water per kilogram of adsorbent, while maintaining an extremely low effluent Ag+ concentration of less than 0.1 mg/L. XPS investigations provided valuable insights into the conversion of Ag+ ions into metallic Ag through the enticement of negatively charged SO3H groups and the in situ reduction facilitated by PDA. This breakthrough not only facilitates the efficient extraction of Ag from wastewater but also paves the way for its environmentally responsible utilization in catalytic reactions.

Facile electrochemiluminescence sensing platform based on high-quantum-yield gold nanocluster probe for ultrasensitive glutathione detection.

This report outlines a highly sensitive and facile electrochemiluminescence (ECL) sensing platform based on a novel high-quantum-yield Au-nanocluster (AuNC) probe for glutathione (GSH) detection. Owing to the prominent quenching effect of GSH on the ECL of the AuNCs, the proposed ECL nanosensor showed a wide response to GSH in the ranges of 1.0 × 10-9-1.0 × 10-5M and 1.0 × 10-5-1.0 × 10-1M and a low detection limit of 3.2 × 10-10M. In addition, the proposed system exhibited good selectivity for GSH in the presence of other chemical/biological interferences. Moreover, since no further functionalization of AuNC-based sensor interface was necessary, together with the stability, high sensitivity and selectivity of the proposed nanosensor, this convenient approach was able to successfully detect GSH in both of human urine samples and blood samples with excellent recoveries, which indicated its promising application under physiological conditions. Of significant importance is that this study not only helps in gaining a better understanding of the applicability of the ECL properties of AuNCs, but also provides a new avenue for the design and development of ECL sensors based on the novel high-quantum-yield AuNC-based probe and other functional-metal-based NC probes.

Valence States Effect on Electrogenerated Chemiluminescence of Gold Nanocluster.

This work elucidated the valence states effect on the electrogenerated chemiluminescence (ECL) performance of gold nanocluster (AuNC). The N-acetyl-l-cysteine-AuNCs (NAC-AuNCs) and the electrochemical reduction method for reducing the AuNCs were first employed to this study. Results demonstrate that the electrochemical reduction degree of the AuNCs depended on the reduction potential, and the enhancement of the ECL signals was positively correlated with the reduction degree of AuNCs, which indicated that the valence state of Au plays a vital role in the ECL performance of AuNCs. Furthermore, the proposed method has been successfully extended to the chemical reduction technique and other nanoclusters. Therefore, an excellent AuNC-based ECL method with various advantages, such as simple preparation, lower toxicity, high sensitivity, and ΦECL, and excellent stability, has been proposed. This approach not only opens up a new avenue for designing and developing ECL device from other functional-metal based NCs, but also extends the huge potential application in the ECL sensing.