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Hierarchical nanostructures of anatase TiO2 with high active surface area has great significance in various applications. Here we have synthesized, highly photoactive hollow bowl like porous spheres of Titanium Dioxide (TiO2) (HBST) by a two-step synthesis procedure i.e. solvothermal strategy followed by thermal treatment. Solvothermally synthesized ultrathin nanoflakes TiO2 (7–8 nm thickness) was examined for the morphological and phase transformation using powder X-ray diffraction (PXRD), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The nanoflakes, initially appeared to be assemble into a hierarchical nanostructure and finally converted to a compact spherical particle followed by hollow bowl like porous spheres of Titanium Dioxide (TiO2) (HBST) on heat treatment. Diffuse reflectance spectroscopy (DRS) measurement confirmed the band gap variation with respect to calcination conditions. Effect of obtained morphologies for photocatalytic and antibacterial activity was assessed using Bisphenol A (BPA) (a potent hazard, requiring immediate clearance) and E. coli (a potent microbial threat !!!). Both photocatalytic and antibacterial studies emphasized the conclusion, that hollow bowl morphology (HBST sample) is the best among all prepared morphologies. Mechanistic studies were carried out to reveal the role of photogenerated radicals and anions responsible for BPA degradation, where BPA degradation follow pseudo-first-order kinetics with rate constant value 0.00548 min−1. Results showed that HBST photocatalyst degraded nearly 89% of initial concentration of BPA in 360 min with high antibacterial efficiency towards E. coli on 1 h UV exposure. Reusability and repeatability tests were carried out to confirm the cyclic stability of the sample.

Insulin resistance is thought to be a common link between obesity and Non-Alcoholic Fatty Liver Disease (NAFLD). NAFLD has now reached epidemic status worldwide and identification of molecules or pathways as newer therapeutic strategies either to prevent or overcome insulin resistance seems critical. Dysregulated hepatic lipogenesis (DNL) is a hallmark of NAFLD in humans and rodents. Therefore, reducing DNL accretion may be critical in the development of therapeutics of NAFLD. In our in vivo model (high-fat-diet fed [HFD] obese mice) we found Zinc oxide nanoparticles (ZnO NPs) significantly decreased HFD-induced hepatic steatosis and peripheral insulin resistance. This protective mechanism of ZnO NPs was signaled through hepatic SIRT1-LKB1-AMPK which restricted SREBP-1c within the cytosol limiting its transcriptional ability and thereby ameliorating HFD mediated DNL. These observations indicate that ZnO NP can serve as a therapeutic strategy to improve the physiological homeostasis during obesity and its associated metabolic abnormalities.

Development of a highly photostable, renal clearable, and nontoxic new NIR probe (CyG) for precise quantification of albumin in different biofluids and liver targeted in vivo albumin visualization is demonstrated. CyG’s inherent property to interact selectively with albumin among different biomolecules in intracellular environment with high degree of sensitivity helps CyG in targeted liver imaging. In addition to its long excitation/emission wavelengths (λex = 740 nm, λem = 804 nm), which are much above the biological tissue opaque window (400–700 nm) ensuring better photon penetration, diminished tissue autofluorescence and high contrasts, its molecular mass and size are far below the renal cutoff and hence, CyG qualifies as imaging material for clinical studies. We anticipate that CyG will provide new strategies to overcome the pitfall of present day albumin detection methods as well as accelerate the detection process at relatively lower costs without compromising the accuracy of detection. Moreover, t...

We demonstrate a strategy for the recognition of As5+ in aqueous solution using a red-emissive probe based on a perylene-Cu2+ ensemble decorated with peripheral free carboxyl functionality. Single crystal analysis helped us to understand the chemical structure of the probe. To the best of our knowledge, this is the first probe for arsenic detection which emits in the red region (λem = 600 nm). The perylene-Cu2+ ensemble exhibited a mega-Stokes shift (>100 nm) with a high degree of selectivity upon interaction with As5+, which indicated that the present probe has the potential to be used as a turn-on optical sensor for selective detection of As5+ with fewer experimental limitations. The detection limit was found to be 26 nM. Inspired by its good emissive properties, the ensemble was further explored for imaging As5+ in live cells. Because of its long-range emissive nature, no autofluorescence from the cellular species was observed during the imaging process. The probe was evaluated to be non-toxic and successfully permeated the cell membrane without the help of any permeabilizing agent to image As5+.