Showing papers by "Nikhil R. Jana published in 2019"

ZnSnO3 Nanoparticle-Based Piezocatalysts for Ultrasound-Assisted Degradation of Organic Pollutants

Abstract: Piezocatalysis is a promising alternative of photocatalysis where the strained state of a piezoelectric material is exploited for electrochemical surface reactions under dark conditions. Among vari...

Selective electrochemical detection of bisphenol A using a molecularly imprinted polymer nanocomposite

Abstract: Bisphenol A is the most common endocrine disrupting chemical found in the environment and human exposure to it leads to a variety of health issues. Thus detection and removal of bisphenol A from industrial waste/soil/drinking water are critical to minimize human consumption. Here we report a molecularly imprinted nanocomposite for selective electrochemical detection of bisphenol A. The nanocomposite has covalently connected polyacrylate, β-cyclodextrin and reduced graphene oxide components with the molecular imprints of bisphenol A for its selective capture via host–guest complexation with β-cyclodextrin. Bisphenol A can be selectively detected in the presence of various bisphenol A analogues via an electrochemical approach where the reduced graphene oxide component induces electrocatalysis. The linear concentration range of bisphenol A detection is 0.02–1.0 μM with a limit of detection (LOD) of 8 nM. This approach has been used for the detection of bisphenol A in contaminated water and may be extended to the detection of bisphenol A among other natural contaminants.

Designed Polymer Micelle for Clearing Amyloid Protein Aggregates via Up-Regulated Autophagy

Abstract: Inhibiting protein aggregation under intra-/extracellular space and clearing protein aggregates from the brain are two critical issues for the treatment of various neurodegenerative diseases. Although a variety of anti-amyloidogenic chemicals/biochemicals have been identified for inhibiting such protein aggregation, clearing protein aggregates is a challenging issue. Here we report a designed biopolymer micelle of 15-30 nm hydrodynamic size that can clear protein aggregates from cells via an up-regulated autophagy process. The polymer has a polyaspartic acid backbone and is functionalized with fatty amine, arginine, and primary amine for inducing self-assembly, enhancing cell uptake, and up-regulating autophagy processes, respectively. The polymer micelle (PM) enters into the cell via lipid raft endocytosis, is transported to the perinuclear region where the protein oligomer/aggregate predominantly localizes, clears aggregated protein from the cell, and enhances the cell's survival against toxic protein aggregates. The designed PM may be used as a drug delivery carrier for anti-amyloidogenic drugs for enhanced efficacy in the treatment of neurodegenerative diseases.

Arginine-Terminated, Chemically Designed Nanoparticle for Direct Cell Translocation

Abstract: Direct cell translocation of nanomaterials is preferred over the endocytotic uptake for various subcellular targeting applications that can bypass the lysosomal trafficking/degradation. Although ar...

AIEgen-Conjugated Magnetic Nanoparticles as Magnetic–Fluorescent Bioimaging Probes

Abstract: Colloidal nanoparticles with a magnetic–fluorescent property and varied surface chemistry have enormous biomedical application potential. However, the synthesis of a high quality of such a nanopart...

Water Dispersible Red Fluorescent Carbon Nanoparticles via Carbonization of Resorcinol

Abstract: Although fluorescent carbon nanoparticles have enormous biomedical application potential, the synthesis of high quality red fluorescent carbon nanoparticles is challenging. Here we report water dis...

Quercetin Encapsulated Polymer Nanoparticle for InhibitingIntracellular Polyglutamine Aggregation

Abstract: Quercetin is a dietary flavonoid that shows effective neuroprotective action in cellular and animal models of Alzheimer’s disease and Huntington’s disease. However, its therapeutic application is limited due to low water solubility and cytotoxicity at the working concentration in the 20–100 μM range. Here we report a nanoparticle form of quercetin (nanoquercetin) that shows antiamyloidogenic performance at lower quercetin concentration (one micromolar) and inhibits polyglutamine (mutant huntingtin) aggregation in Huntington’s disease cell model. Nanoquercetin is composed of a polyaspartic acid-based polymer micelle encapsulated with quercetin (3–5 wt %) and colloidal in nature with 3 day time scale that offers better antiamyloidogenic performance via up-regulated autophagy processes. This work shows that nanoformulation of antiamyloidogenic molecule can have better performance as compared to re...

Riboflavin-Terminated, Multivalent Quantum Dot as Fluorescent Cell Imaging Probe.

Abstract: Bioconjugated nanoparticles are commonly used for targeting cellular/subcellular components, and labeling performance is known to depend on multivalency, i.e., the number of attached biomolecule per particle. However, these multivalency effects are largely unexplored. Here, we show that multivalency of nanoparticle-bound riboflavin controls the cellular interaction, cellular entry/exit mechanism, and subcellular trafficking property. We have synthesized riboflavin-functionalized quantum dot (QD) of 15-25 nm hydrodynamic size with average riboflavin multivalencies of 15, 30, and 70 [designated as QD(RF)15, QD(RF)30, and QD(RF)70, respectively] and investigated their uptake mechanism in riboflavin receptor overexpressed KB cells. We found that increased multivalency from 15 to 70 increases the cellular interaction with QD, shifts the cell uptake mechanism from caveolae-clathrin to exclusive clathrin-mediated endocytosis, and enhances lysosomal trafficking. This work demonstrates the importance of multivalency of bioconjugated molecule at the nanoparticle surface toward biolabeling performance and should be optimized for best performance of designed nanobioconjugate.