1.
Broad-spectrum electrochemical immunosensor based on one-step electrodeposition of AuNP-Abs and Prussian blue nanocomposite for organophosphorus pesticide detection.
Dong, H, Zhao, Q, Li, J, Xiang, Y, Liu, H, Guo, Y, Yang, Q, Sun, X
Bioprocess and biosystems engineering. 2021;(3):585-594
Abstract
Broad-spectrum antibodies can effectively recognize substances with similar structures and have broad application prospects in field rapid detection. In this study, broad-spectrum antibodies (Abs) against organophosphorus pesticides (OPs) were used as sensitive recognition elements, which could effectively recognize most OPs. Gold nanoparticles (AuNPs) have good biocompatibility. It combined with Abs to form a gold-labeled probe (AuNPs-Abs), which enhances the effective binding of antibodies to nanomaterials. Prussian blue (PB) was added to electrodeposition solution to enhance the conductivity, resulting in superior electrochemical performance. The AuNP-Abs-PB composite film was prepared by electrodeposition on the electrode surface to improve the anti-interference ability and stability of the immunosensor. Under the optimal experimental conditions, the immunosensor had a wide detection range (IC20-IC80: 1.82 × 10-3-3.29 × 104 ng/mL) and high sensitivity. Most importantly, it was simple to be prepared and could be used to detect multiple OPs.
2.
Long-term effects of environmentally relevant concentration of Ag nanoparticles on the pollutant removal and spatial distribution of silver in constructed wetlands with Cyperus alternifolius and Arundo donax.
Cao, C, Huang, J, Guo, Y, Yan, CN, Xiao, J, Ma, YX, Liu, JL, Guan, WZ
Environmental pollution (Barking, Essex : 1987). 2019;(Pt A):931-940
Abstract
The widely usage of silver nanoparticles in a range of consumer products inevitably results in its being released to the wastewater. As a result, the potential negative effects associated with AgNPs on wastewater treatment systems need to be assessed to develop the regulatory guidelines. In this paper, the exposure experiment at environmentally relevant concentration (100 μg L-1) were conducted to demonstrate the effects of AgNPs on the pollutant removals in constructed wetlands (CWs) with different plants and the spatial distribution of silver. Before adding AgNPs, the system with Arundo donax (VF2) had the better nitrogen removal than Cyperus alternifolius (VF1). After exposure for about 94 d, the average removal efficiencies of NH4+-N significantly reduced by 32.43% and 23.92%, TN of 15.82% and 17.18% and TP of 22.74% and 20.46% in VF1 and VF2, respectively, while the COD removal had no difference. However, presence of 100 μg L-1 AgNPs for about 450 d showed no inhibition effects on nutrient removals in two experimental CWs. Two wetlands showed high removal efficiencies of about 98% on AgNPs, indicating CWs could play a crucial role to control the AgNPs release to environment. It was found that AgNPs mainly accumulated in the soil layer with the Ag content of 0.45-5.96 μg g-1 dry weight in lower soil and 2.84-11.37 μg g-1 dry weight in upper soil. The roots of Cyperus alternifolius absorbed more AgNPs, with higher bioconcentration factors (1.32-1.44) than that of 0.59 in Arundo donax. The differences of translocation factors on leaves and stems in two test plants showed that AgNPs assimilated by roots in Cyperus alternifolius were more easily transferred to the leaves. The obtained results showed that the macrophyte Cyperus alternifolius could be better choice for immobilization of AgNPs.