Paramita Karfa

Dual-Responsive Polymer Coated Superparamagnetic Nanoparticle for Targeted Drug Delivery and Hyperthermia Treatment

In this work, we have prepared water-soluble superparamgnetic iron oxide nanoparticles (SPIONs) coated with a dual responsive polymer for targeted delivery of anticancer hydrophobic drug (curcumin) and hyperthermia treatment. Herein, superparamagnetic mixed spinel (MnFe2O4) was used as a core material (15-20 nm) and modified with carboxymethyl cellulose (water-soluble component), folic acid (tagging agent), and dual responsive polymer (poly-N isopropylacrylamide-co-poly glutamic acid) by microwave radiation. Lower critical solution temperature (LCST) of the thermoresponsive copolymer was observed to be around 40 °C, which is appropriate for drug delivery. The polymer-SPIONs show high drug loading capacity (89%) with efficient and fast drug release at the desired pH (5.5) and temperature (40 °C) conditions. Along with this, the SPIONs show a very fast increase in temperature (45 °C in 2 min) when interacting with an external magnetic field, which is an effective and appropriate temperature for the localized hyperthermia treatment of cancer cells. The cytocompatibility of the curcumin loaded SPIONs was studied by the methyl thiazol tetrazolium bromide (MTT) assay, and cells were imaged by fluorescence microscopy. To explore the targeting behavior of curcumin loaded SPIONs, a simple magnetic capturing system (simulating a blood vessel) was constructed and it was found that ∼99% of the nanoparticle accumulated around the magnet in 2 min by traveling a distance of 30 cm. Along with this, to explore an entirely different aspect of the responsive polymer, its antibacterial activity toward an E. coli strain was also studied. It was found that responsive polymer is not harmful for normal or cancer cells but shows a good antibacterial property.

Multifunctional fluorescent chalcogenide hybrid nanodots (MoSe2:CdS and WSe2:CdS) as electro catalyst (for oxygen reduction/oxygen evolution reactions) and sensing probe for lead

Manufacturing, designing and developing economic but highly efficient bifunctional catalysts for water splitting technology have become necessary for the large-scale commercialization of regenerative fuel cells. In this work, for the first time, uniformly sized molybdenum/tungsten diselenide and cadmium disulfide nanohybrid quantum dots (MoSe2:CdS and WSe2:CdS NHDs) have been synthesized by a simple hydrothermal technique. The highly exfoliated and defect-abundant nanostructure possess abundant active sites and therefore shows bifunctional behavior with high catalytic activity towards the oxygen reduction/evolution reactions (ORR/OER). The WSe2:CdS NHDs exhibit a small onset potential of +1.1 V vs. RHE and −0.26 V with a small Tafel slope of 49 mV dec−1 and 27 mV dec−1 for OER and ORR, respectively. Moreover, having a quantum sized structure along with CdS also made the NHDs a promising and biocompatible fluorescent probe for metal ion (Pb2+) analysis. The PL emission from NHDs is of high energy and is more intense than the bare NDs, with a very good quantum yield of 87%. The prepared NHDs show a highly stable fluorescence and NHDs coated paper strips were successfully implemented for trace level (20.0 μg L−1) analysis of Pb2+ in real samples (human blood, urine, and polluted water). However, the NHDs were also employed for ultra-trace level (500.0 ng L−1) detection of Pb2+, which confirm the highly selective, sensitive and multi-functional behavior of the prepared NHDs. Therefore, it is envisaged that this work may provide a simple route to synthesize multi-talented 2D layered nanodots suitabile for imaging, sensing, and other energy-related technologies.

Retraction of “Dual-Responsive Polymer Coated Superparamagnetic Nanoparticle for Targeted Drug Delivery and Hyperthermia Treatment”

T Editor retracts this article based on concerns with the microscopy data presented in this published article. Following a reader’s concern, the journal reviewed TEM images in the article (Figures 3A and 3B). Graphics analyses suggested that these images had been enhanced beyond the parameters the journal deems acceptable. These concerns cast doubt on the overall validity of the data presented in this manuscript, not just limited to the specific figures mentioned above and, therefore, the overall conclusions drawn in this paper. The original article was published on April 20, 2015 and retracted on October 5, 2018. Retraction

Role of Magnetic Nanoparticles in Providing Safe and Clean Water to Each Individual

Recent statistics indicate that more people are dying from unsafe water annually than from all forms of violence combined, including war. Providing access to clean water has now become the first priority around the world. But natural water resources have been contaminated by industrial, agricultural, and harmful human activities, and water demands are increasing daily. One of the approaches being explored in many countries to tackle this challenge of increasing access to clean drinking water is the application of nanotechnology. The unique and novel properties of nanoparticles make them well suited for treating water. Nanotechnology offers an opportunity to refine and optimize current techniques and to provide new and novel methods of purifying water. Among them, magnetic nanomaterials have received much attention due to their great biocompatibility, excellent adsorption, and fast separation properties. In this chapter we aim to present all aspects and roles of magnetic nanoparticles (MNPs) in water purification as well as treatment. The chapter covers both the pros and cons of MNPs in water treatment and concludes with recent investigations of the issue of nanotoxicity and its implications for the future.

Development of carbon dots modified fluorescent molecular imprinted Polymer@Ag/AgCl nanoparticle for hepatocellular carcinoma marker

In this work, a sensitive and selective fluorescent molecularly imprinted polymer (MIP) was developed for detection of hepatocellular carcinoma (HCC) biomarker i.e. alpha feto protein (AFP) using Ag/AgCl as platform. Here, the carbon dots and Ag/AgCl nanoparticles were functionalized with vinyl groups and used as functional monomer for synthesis of AFP-imprinted polymer. The imprinted polymer shows a linear range of 3.96 ng mL−1 to 80.0 ng mL−1 with detection limit of 0.42 ng mL−1.The adsorption property of the MIP@Ag/AgCl was studied and shows the high affinity binding towards their target analyte without any cross-reactivity and false-positive or false-negative results.In this work, a sensitive and selective fluorescent molecularly imprinted polymer (MIP) was developed for detection of hepatocellular carcinoma (HCC) biomarker i.e. alpha feto protein (AFP) using Ag/AgCl as platform. Here, the carbon dots and Ag/AgCl nanoparticles were functionalized with vinyl groups and used as functional monomer for synthesis of AFP-imprinted polymer. The imprinted polymer shows a linear range of 3.96 ng mL−1 to 80.0 ng mL−1 with detection limit of 0.42 ng mL−1.The adsorption property of the MIP@Ag/AgCl was studied and shows the high affinity binding towards their target analyte without any cross-reactivity and false-positive or false-negative results.