Electronic and optical competence of TiO2/BiVO4 nanocomposites in the photocatalytic processes.

Nanocomposites with different ratios of titanium dioxide and bismuth vanadate [TiO2]/[BiVO4] give rise to compatible electronic band structure alignment at their interfaces to ensure enhanced photoactivated charge transfer under visible light. The sol-gel method and suitable post-synthesis thermal treatments were used to synthesize different compositions with stabilized anatase phase of TiO2 and monoclinic scheelite polymorph BiVO4. Structural, electronic and optical characterizations were performed and the results were analysed as a function of the stoichiometry, in which both crystalline structures show a clear junction formation among their characteristic stacking planes. Photocatalytic and (photo) electrochemical responses of the nanocomposites were investigated and tested for the degradation of azo dyes (Acid Blue-113, AB-113) (~ 99%) under visible light radiation. The nanocomposite with a mass ratio of (1:10) shows the highest photocatalytic efficiency compared to the other compositions. HRTEM images showed marked regions in which both crystalline structures form a clear junction and their characteristic planes. However, the increase of BiVO4 content in the network overcomes the photocatalytic activity due to the decrease in the reduction potential of the photo-generated electrons with high recombination rates.

Structural and morphological data of RF-Sputtered BiVO4 thin films.

Structural and morphological modulation of rf-sputtered BiVO4 thin films deposited using mechanochemical synthesis prepared BiVO4 nano-powders as sintered target are included in this data article. The crystalline nature of as-prepared films, namely amorphous and crystalline was acquired with time and temperature dependent in-situ high temperature X-ray diffraction (HT-XRD), at a time interval of 1 h. Typical Fourier transform infrared (FT-IR) spectra of annealed thin film of monoclinic BiVO4 structure is given. Furthermore, correlation between morphologies of various substrate temperature fabricated BiVO4 thin films are presented.

Design and evaluation of surface functionalized superparamagneto-plasmonic nanoparticles for cancer therapeutics.

Designing a multifunctional nanomaterial is always considered as a biggest concern in the field of nanomedicine which aims to promote versatile action in a single use from tracking to therapeutics. Therefore, metallic nanoparticles are well exploited as a major platform with the assemblage of surface modifications which can be effectively engaged for plenty of applications. Here, in this work, we have successfully amalgamated gold coated magnetite core-shell nanoparticles along with bio-functionalization of folic acid and doxorubicin to explore its possibility as a distinct nanocargo for cancer nanotheranostics. This unique combination of both magnetic and optical properties makes its function to be more precise. For example, in case of in-vitro drug-release studies more than 75% of drug moieties are released at acidic pH 5.4 and exactly fitting in first order rate kinetics. As gold shell retains the superparamagnetic nature of the core it exhibited high r2 values, and because of large relaxivities (r2/r1) ratio, they are confirmed as T2-weighted contrast agent by MRI. Finally, under microwave of 2.45GHz exhibited enough heat which can induce both apoptosis & necrosis leading to cell death. Thus, we conclude that our nanoparticle can be a multitool for diagnosis and therapeutics for various human diseases.

Plasmonic/Magnetic Multifunctional nanoplatform for Cancer Theranostics.

A multifunctional magneto-plasmonic CoFe2O4@Au core-shell nanoparticle was developed by iterative-seeding based method. This nanocargo consists of a cobalt ferrite kernel as a core (Nk) and multiple layers of gold as a functionalizable active stratum, (named as Nk@A after fifth iteration). Nk@A helps in augmenting the physiological stability and enhancing surface plasmon resonance (SPR) property. The targeted delivery of Doxorubicin using Nk@A as a nanopayload is demonstrated in this report. The drug release profile followed first order rate kinetics optimally at pH 5.4, which is considered as an endosomal pH of cells. The cellular MR imaging showed that Nk@A is an efficient T2 contrast agent for both L6 (r2-118.08 mM-1s-1) and Hep2 (r2-217.24 mM-1s-1) cells. Microwave based magnetic hyperthermia studies exhibited an augmentation in the temperature due to the transformation of radiation energy into heat at 2.45 GHz. There was an enhancement in cancer cell cytotoxicity when hyperthermia combined with chemotherapy. Hence, this single nanoplatform can deliver 3-pronged theranostic applications viz., targeted drug-delivery, T2 MR imaging and hyperthermia.

Microplastics in tourist beaches of Huatulco Bay, Pacific coast of southern Mexico.

The presence and impacts of plastic marine debris (PMD) have been documented in the oceans worldwide, and they deserve special attention. This study is the first to report the presence of microplastics in tourist beaches located in Huatulco Bay, southern Mexico. A total of 70 beach sediment samples (for 2 distinct seasons) were collected from Huatulco Bay in April 2013 and December 2014. The samples were subsequently extracted by scanning electron microscopy (SEM) to identify the fibrous microplastics (diameter<5mm). The maximum number of fibrous materials was found in April 2013 and December 2014 in the Rincón Sabroso beach (48/30g sediment) and the Cuatunalco beach (69/30g sediment), respectively. Overall, a high amount of microplastics is present in the Conejos, Tangolunda, Santa Cruz, and San Agustin beaches. The microplastics are mainly derived from tourism-based activities and effluents discharged from the hotels and restaurants located along the beaches.