Photoluminescent Detection of Human T-Lymphoblastic Cells by ZnO Nanorods

The precise detection of cancer cells currently remains a global challenge. One-dimensional (1D) semiconductor nanostructures (e.g., ZnO nanorods) have attracted attention due to their potential use in cancer biosensors. In the current study, it was demonstrated that the possibility of a photoluminescent detection of human leukemic T-cells by using a zinc oxide nanorods (ZnO NRs) platform. Monoclonal antibodies (MABs) anti-CD5 against a cluster of differentiation (CD) proteins on the pathologic cell surface have been used as a bioselective layer on the ZnO surface. The optimal concentration of the protein anti-CD5 to form an effective bioselective layer on the ZnO NRs surface was selected. The novel biosensing platforms based on glass/ZnO NRs/anti-CD5 were tested towards the human T-lymphoblast cell line MOLT-4 derived from patients with acute lymphoblastic leukemia. The control tests towards MOLT-4 cells were performed by using the glass/ZnO NRs/anti-IgG2a system as a negative control. It was shown that the photoluminescence signal of the glass/ZnO NRs/anti-CD5 system increased after adsorption of T-lymphoblast MOLT-4 cells on the biosensor surface. The increase in the ZnO NRs photoluminescence intensity correlated with the number of CD5-positive MOLT-4 cells in the investigated population (controlled by using flow cytometry). Perspectives of the developed ZnO platforms as an efficient cancer cell biosensor were discussed.This research was funded by MSCA-RISE - Marie Skłodowska-Curie Research and Innovation Staff Exchange (RISE) through the “Novel 1D photonic metal oxide nanostructures for early stage-cancer detection” project, grant number 778157 and by The Belarusian Republican Foundation for Fundamental Research through “Photoluminescent platforms based on nanostructured zinc oxide for detection of human T-lymphoblastic cells”, grant number B20MC-029

Space charge limited current mechanism in Bi2S3 nanowires

We report on the charge transport properties of individual Bi2S3 nanowires grown within the pores of anodized aluminum oxide templates. The mean pore diameter was 80 nm. Space charge limited current is the dominating conduction mechanism at temperatures below 160 K. Characteristic parameters of nanowires, such as trap concentration and trap characteristic energy, were estimated from current–voltage characteristics at several temperatures

Міністерство фінансів України як головний орган управління державними фінансами

The discovery of graphene and its unique properties has inspired researchers to try to invent other two-dimensional (2D) materials. After considerable research effort, a distinct "beyond graphene" domain has been established, comprising the library of non-graphene 2D materials. It is significant that some 2D non-graphene materials possess solid advantages over their predecessor, such as having a direct band gap, and therefore are highly promising for a number of applications. These applications are not limited to nano- and opto-electronics, but have a strong potential in biosensing technologies, as one example. However, since most of the 2D non-graphene materials have been newly discovered, most of the research efforts are concentrated on material synthesis and the investigation of the properties of the material. Applications of 2D non-graphene materials are still at the embryonic stage, and the integration of 2D non-graphene materials into devices is scarcely reported. However, in recent years, numerous reports have blossomed about 2D material-based biosensors, evidencing the growing potential of 2D non-graphene materials for biosensing applications. This review highlights the recent progress in research on the potential of using 2D non-graphene materials and similar oxide nanostructures for different types of biosensors (optical and electrochemical). A wide range of biological targets, such as glucose, dopamine, cortisol, DNA, IgG, bisphenol, ascorbic acid, cytochrome and estradiol, has been reported to be successfully detected by biosensors with transducers made of 2D non-graphene materials.Funding Agencies|EC FP-7 International Research Staff Exchange Scheme (IRSES) Grant [318520]; Linkoping Linnaeus Initiative for Novel Functional Materials (LiLi-NFM); European Union [604391]; Swedish Research Council (VR) Marie Sklodowska Curie International Career Grant [2015-00679]</p

Porous calcium copper titanate electrodes for paracetamol degradation by electro-oxidation via CuO-induced peroxymonosulfate activation

Some drugs cannot be efficiently eliminated using routine wastewater treatments and therefore are considered persistent organic pollutants (POPs). POPs can be removed using advanced oxidation processes. Among these processes, the combination of electrocatalysis and a sulfate-based advanced oxidation process via peroxymonosulfate (PMS) activation is an attractive approach due to its high efficiency, low energy consumption and non-selective attack. It is well known that the type of anode strongly affects the electrocatalysis performance for water treatment. Here, we evaluated perovskites as electrode material due to their unique structural properties and high chemical stability. We fabricated porous anodes of calcium copper titanate (CaCu3Ti4O12; CCTO) with different percentages (20%, 30% and 40%) of polymethyl methacrylate (PMMA) by ball-milling. The samples that included PMMA displayed 50% porosity and pores were homogenously distributed. Morphological measurements show the presence of grain structures and grain boundaries containing CCTO and CuO phases, respectively. CCTO with 30 wt% PMMA (CCTO-30) exhibited the highest CuO phase amount, defect percentage and oxidation–reduction peak, and the smallest resistance. We used the obtained CCTO nanocomposites as anodes in a beaker (210 mL) with PMS (0.5 mM) to treat 10 ppm paracetamol in 50 mM sodium sulfate. After 90 minutes, paracetamol was completely decomposed using CCTO-30 due to PMS activation by a copper catalytic cycle (Cu2+/Cu1+ and Cu2+/Cu3+) to generate ˙SO4− radicals and Cu3+ non-radicals that are selective for its removal

Graphene oxide-induced CuO reduction in TiO2/CaTiO3/Cu2O/Cu composites for photocatalytic degradation of drugs via peroxymonosulfate activation

Contamination of water bodies is a global environmental and human health issue. Conventional water treatment systems cannot efficiently eliminate organic contaminants, particularly drugs. Photocatalysis is a promising, environmentally friendly oxidation process for the removal of such compounds. A key point is the choice of material to be used as photocatalyst. Here, TiO2/CaTiO3/Cu2O/Cu composites were fabricated by adding different amounts (x) of graphene oxide (GO) (x wt% = 1, 3, and 5 %) to CaCu3Ti4O12 powder using the solid-state synthesis method. The produced pellets were sintered under inert nitrogen atmosphere at 1100 °C for 3 h. X-ray diffraction analysis showed that the Cu metal amount was increased upon GO addition, and the UV–Vis diffuse reflectance spectroscopy showed that the spectral response was extended to the visible range. Then, high performance liquid chromatography assessment of paracetamol degradation by a photocatalytic cell using TiO2/CaTiO3/Cu2O/Cu composites with different GO amounts showed that the removal efficiency was increased upon introduction of 0.5 mM peroxymonosulfate (PMS) as active component to generate radical dotSO4‾ radicals. After 3 h under visible light, 96 % of 10 ppm paracetamol was degraded by the composite with 3 % of GO (1 cm2 surface photocatalyst) compared with 50 % by the composite without GO in the same experimental conditions (PMS in 210 mL of aqueous solution). Free radical trapping and the acute toxicity of potential degradation by-products were also investigated. Our results indicate that TiO2/CaTiO3/Cu2O/Cu with 3 % GO displays long-term stability and durability for the photocatalytic removal of pharmaceutical pollutants from wastewater