Electrochemiluminescent detection of Escherichia coli O157:H7 based on Ru(bpy)3 2+/ZnO nanorod arrays.

Foodborne pathogens are perpetual threats to human and animal health. Detection of pathogens requires accurate, sensitive, rapid and point-of-care diagnostic assays. In this study, we described a simple and sensitive electrochemiluminescent (ECL) assay to detect the deadly bacteria Escherichia coli O157:H7 by [Formula: see text]-coated ZnO nanorods arrays (NAs). The [Formula: see text]-coated ZnO NAs were fabricated by immobilizing [Formula: see text] on ZnO NAs with a large specific surface area and good conductivity. An [Formula: see text]-2-(dibutylamino)-ethanol (DBAE) system coated on ZnO NAs exhibits high ECL intensity, rapid response and good stability. This system was further developed as an ECL immunosensor used in the detection of E. coli O157:H7. The proposed ECL immunosensor exhibits a broad detection range within the scope of 200-100 000 CFU ml-1 and quite a low detection limit of 143 CFU ml-1. The high specificity, remarkable reproducibility and good stability offer a sensitive, selective, and convenient pathway for detecting E. coli O157:H7 in the field of food safety and clinical diagnosis.

Organoplatinum-Substituted Polyoxometalate Inhibits ß-amyloid Aggregation for Alzheimer's Therapy.

Aggregated ß-amyloid (Aß) is widely considered as a key factor in triggering progressive loss of neuronal function in Alzheimer's disease (AD), so targeting and inhibiting Aß aggregation has been broadly recognized as an efficient therapeutic strategy for curing AD. Herein, we designed and prepared an organic platinum-substituted polyoxometalate, (Me4 N)3 [PW11 O40 (SiC3 H6 NH2 )2 PtCl2 ] (abbreviated as PtII -PW11 ) for inhibiting Aß42 aggregation. The mechanism of inhibition on Aß42 aggregation by PtII -PW11 was attributed to the multiple interactions of PtII -PW11 with Aß42 including coordination interaction of Pt2+ in PtII -PW11 with amino group in Aß42 , electrostatic attraction, hydrogen bonding and van der Waals force. In cell-based assay, PtII -PW11 displayed remarkable neuroprotective effect for Aß42 aggregation-induced cytotoxicity, leading to increase of cell viability from 49 % to 67 % at a dosage of 8 µm. More importantly, the PtII -PW11 greatly reduced Aß deposition and rescued memory loss in APP/PS1 transgenic AD model mice without noticeable cytotoxicity, demonstrating its potential as drugs for AD treatment.

Electrochemical biosensor for cancer cell detection based on a surface 3D micro-array.

The detection of rare circulating tumour cells (CTCs) in patients' blood is crucial for the early diagnosis of cancer, highly precise cancer therapy and monitoring therapeutic outcomes in real time. In this study we have developed an efficient strategy to capture and detect CTCs from the blood of cancer patients using a benzoboric acid modified gold-plated polymeric substrate with a regular 3D surface array. Compared with the smooth substrate, the substrate with the surface 3D microarrays exhibited a higher capture efficiency, i.e. 3.8 times that afforded by the smooth substrate. Additionally, due to the reversible reaction between the benzoboric acid on the 3D microarray and the sialic acid on CTCs, our strategy allowed for easy detachment of the captured CTCs from the substrate without causing critical damage to the cells. This will be of benefit for gaining further access to these rare cells for downstream characterization. The proposed strategy provides several advantages, including enhanced capture efficiency, high sensitivity, low cost and recovery of isolated CTCs, and could become a promising platform for early stage diagnosis of cancer.

Highly Efficient, Near-Infrared and Visible Light Modulated Electrochromic Devices Based on Polyoxometalates and W18O49 Nanowires.

Over the past years the performance of electrochromic smart windows with the promising potential for significant energy savings has been progressively improved; however, the electrochromic windows have not yet to come into use at scale mainly because the electrochromic materials suffer from some significant drawbacks such as low coloration efficiency, slow switching time, bad durability and poor functionality. Herein, we fabricate the optically modulated electrochromic smart devices through sequential deposition of the crown-type polyoxometalates, K28Li5H7P8W48O184·92H2O (P8W48), and W18O49 nanowires. Unlike most reported electrochromic smart devices, the resulting P8W48 and W18O49 nanocomposites allow active and selective manipulation of the transmittance of near-infrared (750-1360 nm) and visible light (400-750 nm) by varying the applied potential. Furthermore, thanks to the stable nature of both P8W48 and W18O49 and precise structural control over the nanocomposites, the prepared electrochromic smart devices exhibit high efficiency, quick response and excellent stability.

Multifunctional Theranostic Agent of Cu2(OH)PO4 Quantum Dots for Photoacoustic Image-Guided Photothermal/Photodynamic Combination Cancer Therapy.

Image-guided phototherapy is considered to be a prospective technique for cancer treatment because it can provide both oncotherapy and bioimaging, thus achieving an optimized therapeutic efficacy and higher treatment accuracy. Compared to complicated systems with multiple components, using a single material for this multifunctional purpose is preferable. In this work, we strategically fabricated poly(acrylic acid)- (PAA-) coated Cu2(OH)PO4 quantum dots [denoted as Cu2(OH)PO4@PAA QDs], which exhibit a strong near-infrared photoabsorption ability. As a result, an excellent photothermal conversion ability and the photoactivated formation of reactive oxygen species could be realized upon NIR irradiation, concurrently meeting the basic requirements for photothermal and photodynamic therapies. Moreover, phototherapeutic investigations on both cervical cancer cells in vitro and solid tumors of an in vivo mice model illustrated the effective antitumor effects of Cu2(OH)PO4@PAA upon 1064-nm laser irradiation, with no detectable lesions in major organs during treatment. Meanwhile, Cu2(OH)PO4@PAA is also an exogenous contrast for photoacoustic tomography (PAT) imaging to depict tumors under NIR irradiation. In brief, the Cu2(OH)PO4@PAA QDs prepared in this work are expected to serve as a multifunctional theranostic platform.