Optically detected magnetic resonance spectroscopic analyses on the role of magnetic ions in colloidal nanocrystals.

Incorporating magnetic ions into semiconductor nanocrystals has emerged as a prominent research field for manipulating spin-related properties. The magnetic ions within the host semiconductor experience spin-exchange interactions with photogenerated carriers and are often involved in the recombination routes, stimulating special magneto-optical effects. The current account presents a comparative study, emphasizing the impact of engineering nanostructures and selecting magnetic ions in shaping carrier-magnetic ion interactions. Various host materials, including the II-VI group, halide perovskites, and I-III-VI2 in diverse structural configurations such as core/shell quantum dots, seeded nanorods, and nanoplatelets, incorporated with magnetic ions such as Mn2+, Ni2+, and Cu1+/2+ are highlighted. These materials have recently been investigated by us using state-of-the-art steady-state and transient optically detected magnetic resonance (ODMR) spectroscopy to explore individual spin-dynamics between the photogenerated carriers and magnetic ions and their dependence on morphology, location, crystal composition, and type of the magnetic ion. The information extracted from the analyses of the ODMR spectra in those studies exposes fundamental physical parameters, such as g-factors, exchange coupling constants, and hyperfine interactions, together providing insights into the nature of the carrier (electron, hole, dopant), its local surroundings (isotropic/anisotropic), and spin dynamics. The findings illuminate the importance of ODMR spectroscopy in advancing our understanding of the role of magnetic ions in semiconductor nanocrystals and offer valuable knowledge for designing magnetic materials intended for various spin-related technologies.

Sonochemically Prepared BSA Microspheres as Adsorbents for the Removal of Organic Pollutants from Water.

This work investigates, for the first time, the application of sonochemically prepared bovine serum albumin (BSA) microspheres (BSAMS) as adsorbents of industrial organic pollutant dyes, such as rhodamine B (RhB), rhodamine 6G (Rh6G), and methylene blue (MB). These dyes also serve as model compounds for other organic pollutants such as bisphenol A and 2-nitrophenol. Adsorption kinetics of the dyes by the BSAMS was studied using pseudo-first-order (PFO) and pseudo-second-order (PSO) kinetic models. It was found that RhB follows PFO, with an adsorption capacity, qe,cal, of 7.9 mg/g, which was closer to the experimental adsorption capacity of qe,exp. of 7.6 mg/g. However, MB and Rh6G were controlled by PSO kinetics, with a qe,cal of 5.6 mg/g for MB and 6.6 mg/g for Rh6G, closer to the experimental adsorption capacity of 5.7 and 6.4 mg/g, respectively. The intraparticle diffusion (ID) model applied to the three dyes indicated multi-linearity with ID as the rate-limiting step in the adsorption process. Furthermore, the adsorption equilibria for each of the organic pollutants were studied through various isotherm models such as Langmuir, Freundlich, Temkin, and Halsey, which indicated physical interaction between the BSAMS and the dye pollutants, thus suggesting the applicability of the BSAMS as pollutant adsorbent materials. It was found that the BSAMS can effectively remove RhB, MB, and Rh6G from wastewater with efficiencies of 95.5, 83.3, and 97.9%, respectively.

Glucose-6-phosphate dehydrogenase deficiency with coinherited Gaucher disease: A rare association.

ABSTRACT: Anemia coexisting with Gaucher disease (GD) is often associated with non-hemolytic processes. Few cases of GD with autoimmune hemolytic anemia have been reported. However, literature on GD with concomitant nonimmune hemolytic anemia is scarce. A 1-year 6-month-old male child presented in 2018 with complaints of palpable mass in left upper abdomen, fever, cough, and vomiting. On examination, he had pallor, hepatosplenomegaly of 2 cm and 8 cm below costal margin, respectively. A clinical diagnosis of hemolytic anemia was suspected. Complete blood count revealed Hb---6.7 g/dL, TLC---8.9 × 10 3 /µL, platelet count---180 × 10 3 /µL. Peripheral smear showed predominantly microcytic hypochromic anemia with moderate degree of anisocytosis, many nucleated red blood cells, few schistocytes, polychromatophils and corrected reticulocyte count 7.89%. S. Bilirubin was 1.1 mg/dL. Hb high-performance liquid chromatography (HPLC) of the child and his parents was within normal limit. Hematological work up revealed negative results for direct Coombs' test, osmotic fragility test, and sickling test. Test for Glucose-6-phosphate dehydrogenase deficiency was positive (39 units/trillion RBC, normal 146--376). He was transfused intermittently and given steroids to manage his anemia. He was on regular follow up during which his blood counts revealed persistent anemia and thrombocytopenia. In view of this, bone marrow was performed to exclude myelofibrosis. Aspirate smears were cellular and showed normoblastic erythroid hyperplasia. Numerous large histiocytes with basophilic fibrillary cytoplasm exhibiting "crumpled tissue paper" appearance were seen. Similar findings were seen on bone marrow trephine biopsy. Genetic testing revealed pathogenic variations in the GBA gene. Beta glucosidase enzyme levels were low while chitotriosidase was raised (1109.19 nmol/hr/mL). A final diagnosis of G6PD with GD was made. The present study shows rare association of GD with Glucose-6-phosphate dehydrogenase deficiency.

Study of growth differentiation factor-15 in polytransfused children with ß-thalassemia.

Background: Ineffective erythropoiesis is a predominant feature in ß-thalassemia major (ß-TM), causing marked erythroid expansion leading to highly raised levels of growth differentiation factor-15 (GDF-15), which, in turn, suppresses hepcidin production in liver resulting in increased iron absorption from gut. We aim to study the serum GDF-15 in polytransfused ß-TM patients and its correlation with serum ferritin and serum hepcidin. Method: Thirty-nine polytransfused ß-TM children aged between 5 and 17 years and 33 age- and gender-matched healthy controls were enrolled in the study. Complete blood count, serum GDF-15, serum ferritin, and serum hepcidin were performed. Results: The mean serum GDF-15, serum hepcidin, and serum ferritin levels were 638.65 ± 306.96 pg/ml, 108.21 ± 191.30 ng/ml, and 2274.60 ± 1216.08 ng/ml, respectively, which were significantly higher than control group (P < 0.001, P = 0.003, P < 0.001, respectively). There was significant positive correlation of GDF-15 with blood transfusions (r = 0.415, P = 0.009), positive correlation with serum ferritin (r = 0.653, P = 0), and significant negative correlation with serum hepcidin (r = -0.508, P = 0.001). Conclusion: The findings of the present study suggest that GDF-15 is an important regulator of hepcidin in ß-TM patients. GDF-15 and serum hepcidin together can be used to monitor iron overload and its related complications in such patients.

Colloidal Control of Branching in Metal Chalcogenide Semiconductor Nanostructures.

Colloidal syntheses of metal chalcogenides yield nanostructures of various 1D, 2D, and 3D nanocrystals (NCs), including branched nanostructures (BNSs) of nanoflowers, tetrapods, octopods, nanourchins, and more. Efforts are continuously being made to understand the branching mechanism in colloidally prepared metal chalcogenides for tailor-making them into various morphologies for dedicated applications in solar cells, light-emitting diodes, stress sensor devices, and near-infrared photodetectors. The vital role of precursors and ligands has widely been recognized in directing nanocrystal morphology during the colloidal synthesis of metal chalcogenide nanostructures. Moreover, a few basic branching mechanisms in nanocrystals have also been derived from decades-long observations of branching in NCs. This Perspective (a) accounts for the mediation of branching in In2S3, PbS, MoSe2, WSe2, and WS2; (b) analyzes the underlying mechanisms; and (c) gives a future perspective toward better controlling the BNSs' morphologies and their impact on applications.

Endothelial Activation Markers in Polytransfused Children with Beta Thalassemia: Study from a Tertiary Care Centre in India.

Beta thalassemia major is associated with a subclinical hypercoagulable state. Endothelial activation markers like soluble Intercellular adhesion molecule (sICAM-1) and E-selectin have been implicated in the pathogenesis of endothelial dysfunction and hemostatic alterations. In this study we aimed to study serum levels of sICAM-1 and E-selectin in polytransfused children with ß thalassemia major and their association with serum ferritin and D-dimer levels. Sixty-two polytransfused ß-thalassemia major children aged between 5 and 17 years and 26 age and gender matched healthy controls were enrolled in the study. Complete blood count with peripheral smear, liver function tests, serum ferritin, coagulation tests [PT, APTT, D-dimer] and endothelial activation marker tests [ICAM-1 and E-selectin] were performed. PT, APTT and D-dimer levels were significantly higher in beta-thalassemia major patients than in control group (p = 0.003, p < 0.001, p < 0.001 respectively). Mean ICAM-1 and E-selectin levels were 731.34 ± 343.97 ng/ml and 111.75 ± 40.13 ng/ml respectively which were significantly higher than control group (p < 0.001, p < 0.001 respectively). No significant correlation of ICAM-1 and E-selectin was observed with serum ferritin, PT, APTT and D-dimer levels. The findings of the present study suggest that there is ongoing subclinical activation of coagulation cascade and fibrinolytic system in these patients. Endothelial activation markers may be used as early indicators of endothelial dysfunction to assess the thrombotic complications in beta thalassemia.

Designing Natural Polymer-Based Capsules and Spheres for Biomedical Applications-A Review.

Natural polymers, such as polysaccharides and polypeptides, are potential candidates to serve as carriers of biomedical cargo. Natural polymer-based carriers, having a core-shell structural configuration, offer ample scope for introducing multifunctional capabilities and enable the simultaneous encapsulation of cargo materials of different physical and chemical properties for their targeted delivery and sustained and stimuli-responsive release. On the other hand, carriers with a porous matrix structure offer larger surface area and lower density, in order to serve as potential platforms for cell culture and tissue regeneration. This review explores the designing of micro- and nano-metric core-shell capsules and porous spheres, based on various functions. Synthesis approaches, mechanisms of formation, general- and function-specific characteristics, challenges, and future perspectives are discussed. Recent advances in protein-based carriers with a porous matrix structure and different core-shell configurations are also presented in detail.

Antibacterial activities of microwave-assisted synthesized polypyrrole/chitosan and poly (pyrrole-N-(1-naphthyl) ethylenediamine) stimulated by C-dots.

Polypyrrole grafted with chitosan (PPy-g-CS) and poly (pyrrole-N-(1-naphthyl) ethylenediamine, a copolymer, (COP) have been synthesized by a one-step microwave procedure with carbon dots(C-Dots) as initiators. The electrostatic interaction between the positively charged polymers and negatively charged microbial cell membranes is widely anticipated to be responsible for cellular lysis. However, Escherichia coli exposed to PPy-g-CS (zeta potential = +46.9 mV) was completely perished after 3 h while COP (zeta potential = +64.1 mV) exhibited no antimicrobial effect. The two polymers were capable of eradicating Staphylococcus aureus, implying the charged effect is the main mechanism of cell death. The two polymers could also chelate calcium and other nutrients as well as form an external barrier to suppress the penetration of essential nutrients to support microbial survival and proliferation. In particular, pyrrole grafted chitosan was reasoned to stack onto the bacterial surface to impede the mass transfer and suppress the bacterial metabolic activity. The binding of chitosan to teichoic acids, essential acids of Gram-positive bacteria, would provoke a sequence of events and lead to bacterial death.

Entrapment and release kinetics study of dyes from BSA microspheres forming a matrix and a reservoir system.

Two kinds of Bovine Serum Albumin (BSA)-loaded microspheres were prepared in water-organic bilayer systems using ultrasonic irradiation. The first method included an aqueous solution of BSA and water-soluble dye together, mixed with dodecane, that upon sonication formed a matrix system where the dye is concentrated in the protein shell. The other system included an aqueous solution of BSA mixed with octanol-soluble dye that, upon sonication, formed a reservoir system in which the dye filled the inner volume of the microspheres. Each of these microspheres was prepared with two different dyes and their leaching profiles into pure solvents were studied using UV-vis spectrometry. Fast leaching was observed at the beginning for both systems, which levelled-off after a certain time. For the matrix system, an equilibrium state was obtained after 100-200 hours, whereas for the reservoir system, leaching occurred much faster, within 1-3 hours. Such systems can serve as models for drug delivery agents.

Topical Nanostructured Lipid Carrier Based Hydrogel of Mometasone Furoate for the Treatment of Psoriasis.

OBJECTIVE: The aim of the present study was to develop and evaluate nanostructured lipid carrier based topical hydrogel of mometasone furoate for the treatment of psoriasis. METHOD: Drug loaded NLCs were successfully developed by microemulsion technique. Pseudo ternary phase diagrams were constructed using different combinations of surfactant and co-surfactants to study the microemulsion existence range. Different compositions were selected from the phase diagram showing maximum microemulsion region and were converted into NLCs by dilution in water (1:20). The optimized formulation was characterised for droplet size, zeta potential, entrapment efficiency and morphology was studied using Transmission Electron Microscopy. Ex vivo permeation studies were carried out using Wistar rat skin. The potential of this formulation in treating psoriatic inflammation was studied using imiquimod induced skin inflammation animal model. RESULTS: The optimized formulation (F4) has droplet size of 163.2±0.522 nm, zeta potential - 0.086±0.099 mV and entrapment efficiency of 60.0±0.187%. Transmission electron microscopy confirmed spherical shape of nanostructured lipid carrier. Carbopol 940 was used to convert NLC dispersion into NLC based hydrogel to improve its viscosity for topical administration. Drug permeation studies showed prolonged drug release from the NLC based gel as compared to marketed formulation following Higuchi release kinetics. The skin deposition of MF loaded NLC based hydrogel was found to 2.5 fold higher than marketed formulation with primary skin irritation index of 0.20. In vivo studies showed complete clearance of parakeratosis by treatment with the prepared NLC formulation. Accelerated stability studies signify high robustness scale of optimized formulation under one month storage period. CONCLUSION: The prepared NLC based formulation has proved to be a promising carrier system for the treatment of psoriasis.

Organic-Inorganic Composite Films Based on Gd3Ga3Al2O12:Ce Scintillator Nanoparticles for X-ray Imaging Applications.

Organic-inorganic nanocomposite self-standing films of Gd3Ga3Al2O12 (GGAG) uniformly dispersed in poly(methyl methacrylate) (PMMA) and polystyrene polymer are prepared for radiography application. GGAG:Ce nanoscintillator has been chosen because of its high light output and fast decay time. The nanopowder of GGAG is synthesized by coprecipitation method and dispersed in the polymer matrix by a simple blending technique. The nanocomposite films of thickness in the range of 150-450 µm with a very high inorganic content is achieved by this technique. These films are characterized by their uniformity, optical absorption, photoluminescence, and radioluminescence. These films are further tested for their application in radiography by recording X-ray images using a commercially available charge-coupled device camera. A resolution of 10 lp/mm is obtained using GGAG:PMMA composite film with 50% loading, confirming their application in imaging devices.