Exploiting Spintronics at Room Temperature for Long-Wave Infrared Nanophotonic Digital Bolometers.

Digital detectors that "click" such as avalanche diodes and superconducting nanowire sensors are widely used in visible and near-infrared frequencies within the fields of quantum communications, imaging and metrology. On the other hand, the vast field of infrared bolometry has been dominated by analog detectors barring a few examples which require extremely challenging low temperature environments. Here, we propose and demonstrate a nanophotonic bolometer designed by engineering spintronic materials and dimensions to provide "clicks" from thermally activated transitions between two discrete magnetization states.

A Peripheral-Free True Random Number Generator Based on Integrated Circuits Enabled by Atomically Thin Two-Dimensional Materials.

A true random number generator (TRNG) is essential to ensure information security for Internet of Things (IoT) edge devices. While pseudorandom number generators (PRNGs) have been instrumental, their deterministic nature limits their application in security-sensitive scenarios. In contrast, hardware-based TRNGs derived from physically unpredictable processes offer greater reliability.

Biocompatible thermoresponsive -isopropyl--(3-(isopropylamino)-3-oxopropyl)acrylamide-based random copolymer: synthesis and studies of its composition dependent properties and anticancer drug delivery efficiency.

A new acrylamide monomer, -isopropyl--(3-(isopropylamino)-3-oxopropyl)acrylamide (M3i), consisting of both isopropyl and isopropylamidopropyl moieties, has been synthesized from isopropylamine and -isopropylacrylamide an aza-Michael addition reaction followed by amidation with acryloyl chloride. The homopolymer of M3i (polyM3i) and a series of random copolymers of M3i and poly(ethylene glycol)methyl ether acrylate (PEGA: CHCHCO(CHCHO)Me, = 480, = 9 on average) with varying compositions have been synthesized reversible addition-fragmentation chain transfer polymerization using 2-(dodecylthiocarbonothioylthio)-2-methylpropionic acid (DDMAT) as well as 1-phenylethyl phenyl dithioacetate (PEPD) as a RAFT agent. These polymers have been characterized by H NMR, FTIR, GPC, UV-Vis, fluorescence, TGDTA, DSC, DLS, and TEM techniques.

Correction: Nanochannel conduction in piezoelectric polymeric membrane using swift heavy ions and nanoclay.

[This corrects the article DOI: 10.1039/C3RA23176C.].

Colorimetric detection of hydrogen peroxide and cholesterol using FeO-brominated graphene nanocomposite.

FeO-brominated graphene (FeO-GBR) nanocomposites were synthesized via an in situ method using the precursors FeSO.7HO and GBR in different (1:1, 1:2, 2:1, 1:5, 1:10, 1:20, and 5:1) weight ratios at pH 11.5.

Gelatin grafted poly(D,L-lactide) as an inhibitor of protein aggregation: An in vitro case study.

Amyloids are a group of proteins that are capable of forming aggregated amyloid fibrils, which is responsible for many neurodegenerative diseases including Alzheimer's disease (AD). In our previous study, synthesis and characterization of star-shaped poly(D,L-lactide)-b-gelatin (ss-pLG) have been reported. In the present work, we have extended our work to study ss-pLG against protein aggregation.

Doxorubicin loaded pH responsive biodegradable ABA-type Amphiphilic PEG-b-aliphatic Polyketal-b-PEG block copolymer for therapy against aggressive murine lymphoma.

A novel ABA-type polyethylene glycol (PEG)-b-polyketal (PK)-b-PEG block copolymer was synthesized via click reactions between the monoazido-monomethoxy-PEG and dialkyne terminated aliphatic polyketal with no carboxylic/amide linkages. Formation of the novel block copolymer was confirmed by H NMR, GPC, TGA, and DSC studies. The formed copolymer has shown faster degradation at acidic pH.

Highly selective fluorescence 'turn off' sensing of picric acid and efficient cell labelling by water-soluble luminescent anthracene-bridged poly(N-vinyl pyrrolidone).

A novel, water-soluble, luminescent anthracene-bridged AA-type bi-arm poly(N-vinylpyrrolidone) (ATC-PNVP) was synthesized using a click reaction between alkyne-terminated PNVP and 9,10-bis(azidomethyl)anthracene. The resultant anthracene-bridged PNVP (ATC-PNVP) was characterized using 1H NMR, FTIR, UV-Vis, and fluorescence spectroscopic methods and GPC analysis. ATC-PNVP showed effective fluorescence properties in an aqueous medium.

Fluorescent-functionalized graphene oxide for selective labeling of tumor cells.

Fluorescence probe has attracted significant attention for biomedical imaging in recent years due to their high resolution at the cellular level. Organic-based fluorescent probes with high quantum yield are widely applied in bioimaging, but most of them suffer from a serious obstacle called aggregation-caused quenching in cellular systems. New fluorophore has been designed through functionalization of graphene oxide which emphatically exhibits aggregation-induced emission along with pH-responsive nanoprobe.

Grafted cyclodextrin as carrier for control drug delivery and efficient cell killing.

The presence of hydroxyl groups in cyclodextrin (CD) makes it highly hydrophilic and simultaneously allows its chemical modification to graft polyurethane to control the drug release for longer period of time by maintaining the hydrophobic-hydrophilic balance through varying extent of grafting. Grafting of polyurethane on CD is confirmed through H NMR and molecular weight measurement while FTIR and UV visible studies further support grafting and emphasize the interaction among polymer chains as a whole. Degree of grafting is evaluated from the integrated peak area in NMR spectra.

Efficacy of polyurethane graft on cyclodextrin to control drug release for tumor treatment.

Hydrophilicity of cyclodextrin is controlled through grafting of polyurethane of varying graft density, thereby maintain the hydrophilic-hydrophobic balance, to sustain the drug delivery rate for better tumor treatment. Grafting is verified through nuclear magnetic resonance (H NMR) and other spectroscopic techniques along with the hydrodynamic volume measurement of grafted species and the degree of substitution has been calculated from the integrated peak areas. Thermal and mechanical stability of the graft copolymers have improved significantly with respect to cyclodextrin and the formation of smaller blobs having larger in number has been obtained from small angle neutron scattering, atomic force microscopy and optical images.

Cell proliferation influenced by matrix compliance of gelatin grafted poly(d,l-Lactide) three dimensional scaffolds.

Surface and mechanical properties of the biomaterials are determinants of cellular responses. In our previous study, star-shaped poly(d,l-Lactide)-b-gelatin (ss-pLG) was reported for possessing improved cellular adhesion and proliferation. Here, we extended our investigation to establish the cellular compatibility of gelatin-grafted PDLLA with respect to mechanical properties of biological tissues.

Functionalized Graphene Tagged Polyurethanes for Corrosion Inhibitor and Sustained Drug Delivery.

Surface functionalization of graphene oxide with sulfonate group and subsequent grafting with polyurethane chains leads to the significant improvement in the properties of polymer and modified graphene as a filler. Modification of graphene oxide is revealed through spectroscopy while grafting of polymer chain over sulfonated graphene is confirmed through H NMR and other techniques. Higher order of self-assembly phenomena is observed in nanohybrids as compared to pure polymer through greater interaction between polymer chain and sulfonated graphene.

Osteoconductive Amine-Functionalized Graphene-Poly(methyl methacrylate) Bone Cement Composite with Controlled Exothermic Polymerization.

Bone cement has found extensive usage in joint arthroplasty over the last 50 years; still, the development of bone cement with essential properties such as high fatigue resistance, lower exothermic temperature, and bioactivity has been an unsolved problem. In our present work, we have addressed all of the mentioned shortcomings of bone cement by reinforcing it with graphene (GR), graphene oxide (GO), and surface-modified amino graphene (AG) fillers. These nanocomposites have shown hypsochromic shifts, suggesting strong interactions between the filler material and the polymer matrix.

Controlled drug release through regulated biodegradation of poly(lactic acid) using inorganic salts.

Biodegradation rate of poly(lactic acid) (PLA) has been regulated, both increase and decrease with respect to the biodegradation of pure PLA, by embedding meager amount of inorganic salts in polymer matrix. Biodegradation is performed in enzyme medium on suspension and film and the extent of biodegradation is measured through spectroscopic technique which is also verified by weight loss measurement. Media pH has been controlled using trace amount of inorganic salt which eventually control the biodegradation of PLA.

Tailored Chemical Properties of 4-Arm Star Shaped Poly(d,l-lactide) as Cell Adhesive Three-Dimensional Scaffolds.

Biodegradable poly(lactic acid) (PLA) is widely used to fabricate 3D scaffolds for tissue regeneration. However, PLA lacks cell adhering functional moieties, which limit its successful application in tissue engineering. Herein, we have tailored the cell adhesive properties of star shaped poly(d,l-lactide) (ss-PDLLA) by grafting gelatin to their 4 arms.

Brominated Graphene as Mimetic Peroxidase for Sulfide Ion Recognition.

Brominated graphene (GBR) with ∼3% bromine content has shown novel peroxidase mimetic activity toward 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of HO Optimum activity has been observed at pH 4.48 and after a minimum ∼30 min of equilibration time. Among the different analytes studied using the sensor combining TMB, HO, and GBR in phosphate buffer of pH 4.

Study of the Fluorescence Based Applications of Pyrene-Tagged Poly(-vinyl-2-pyrrolidone).

In this study we have explored the fluorescence based applications of luminescent pyrene-tagged PNVP (PyPNVP) reported in our previous work (Int. J. Polym.

Methotrexate-Loaded Four-Arm Star Amphiphilic Block Copolymer Elicits CD8+ T Cell Response against a Highly Aggressive and Metastatic Experimental Lymphoma.

We have synthesized a well-defined four-arm star amphiphilic block copolymer [poly(DLLA)-b-poly(NVP)]4 [star-(PDLLA-b-PNVP)4] that consists of D,L-lactide (DLLA) and N-vinylpyrrolidone (NVP) via the combination of ring-opening polymerization (ROP) and xanthate-mediated reversible addition-fragmentation chain transfer (RAFT) polymerization. Synthesis of the polymer was verified by 1H NMR spectroscopy and gel permeation chromatography (GPC). The amphiphilic four-arm star block copolymer forms spherical micelles in water as demonstrated by transmission electron microscopy (TEM) and 1H NMR spectroscopy.

Collection-limited theory interprets the extraordinary response of single semiconductor organic solar cells.

The bulk heterojunction (BHJ) organic photovoltaic (OPV) architecture has dominated the literature due to its ability to be implemented in devices with relatively high efficiency values. However, a simpler device architecture based on a single organic semiconductor (SS-OPV) offers several advantages: it obviates the need to control the highly system-dependent nanoscale BHJ morphology, and therefore, would allow the use of broader range of organic semiconductors. Unfortunately, the photocurrent in standard SS-OPV devices is typically very low, which generally is attributed to inefficient charge separation of the photogenerated excitons.

Targeted delivery of doxorubicin-loaded poly (ε-caprolactone)-b-poly (N-vinylpyrrolidone) micelles enhances antitumor effect in lymphoma.

Background: The present study was motivated by the need to design a safe nano-carrier for the delivery of doxorubicin which could be tolerant to normal cells. PCL63-b-PNVP90 was loaded with doxorubicin (6 mg/ml), and with 49.8% drug loading efficiency; it offers a unique platform providing selective immune responses against lymphoma.

Synthesis and study of the properties of stereocontrolled poly(N-isopropylacrylamide) gel and its linear homopolymer prepared in the presence of a Y(OTf)3 Lewis acid: effect of the composition of methanol-water mixtures as synthesis media.

Poly(N-isopropylacrylamide) (PNIPAM) hydrogels and the corresponding linear homopolymers were synthesized in different methanol-water mixtures (x(m) = 0, 0.13, 0.21, 0.

Threshold of hierarchical percolating systems.

Many modern nanostructured materials and doped polymers are morphologically too complex to be interpreted by classical percolation theory. Here, we develop the concept of a hierarchical percolating (percolation-within-percolation) system to describe such complex materials and illustrate how to generalize the conventional percolation to double-level percolation. Based on Monte Carlo simulations, we find that the double-level percolation threshold is close to, but definitely larger than, the product of the local percolation thresholds for the two enclosed single-level systems.

Synthesis and characterization of stereocontrolled poly(N-isopropylacrylamide) hydrogel prepared in the presence of Y(OTf)3 Lewis acid.

Macroporous poly(N-isopropylacrylamide) (PNIPAM) hydrogels have been prepared in methanol-water (1:1, v/v) mixture in the presence of 0, 0.05, 0.1, 0.