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1.
Small ; 20(24): e2309572, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38155584

ABSTRACT

Exploring combinatorial materials, as well as rational device configuration design, are assumed to be the key strategies for deploying versatile electrochemical devices. MXene sheets have revealed a high hydrophilic surface with proper mechanical and electrical characteristics, rendering them supreme additive candidates to integrate in electrospun electrochemical power tools. The synergetic effects of MXene 2D layers with the nanofibrous networks can boost actuator responsive ability, battery capacity retention, fuel cell stability, sensor sensitivity, and supercapacitor areal capacitance. Their superior mechanical features can be endowed to the electrospun layers through the embedding of the MXene additive. In this review, the preparation and inherent features of the MXene configurations are briefly evaluated. The fabrication and overall performance of the MXene-loaded nanofibers applicable in electrochemical actuators, batteries, fuel cells, sensors, and supercapacitors are comprehensively figured out. Eventually, an outlook on the future development of MXene-based electrospun composites is presented. A substantial focus has been devoted to date to engineering conjugated MXene and electrospun fibrous frames. The potential performance of the MXene-decorated nanofibers presents a bright future of nanoengineering toward technological growth. Meanwhile, a balance between the pros and cons of the synthesized MXene composite layers is worthwhile to consider in the future.

2.
ACS Omega ; 8(46): 43388-43407, 2023 Nov 21.
Article in English | MEDLINE | ID: mdl-38027388

ABSTRACT

Lithium-ion batteries (LIBs) are accounted as promising power tools, applicable in a wide range of energy-based equipment, from portable devices to electric vehicles. Meanwhile, approaching a cost-effective, environmentally friendly, and safe LIB array has remained sluggish yet. In this regard, cellulose, as a nontoxic natural renewable polymer, has provided a stable and cohesive electrode structure with excellent mechanical stability and reduced electrode cracking or delamination during cycling. Additionally, the porous configuration of the cellulose allows for efficient and faster ion transport as a separator component. Miniaturizing cellulose and its derivatives have revealed more fabulous characteristics for the anode, cathode, and separator resulting from the increased surface-to-volume ratio and superior porosity, as well as their thin and lightweight architectures. The focal point of this review outlines the challenges relating to the extraction and electrospinning of cellulose-based nanofibers. Additionally, the efforts to employ these membranes as the LIBs' components are elucidated. Correspondingly, despite the great performance of cellulose-based LIB structures, a research gap is sensed in this era, possibly due to the difficulties in processing the electrospun cellulose fibers. Hence, this review can provide a source of recent advancements and innovations in cellulose-based electrospun LIBs for researchers who aim to develop versatile battery structures using green materials, worthwhile, and eco-friendly processing techniques.

3.
ACS Appl Mater Interfaces ; 15(47): 55055-55064, 2023 Nov 29.
Article in English | MEDLINE | ID: mdl-37969108

ABSTRACT

The current collector serves as a crucial element in supercapacitors, acting as a medium between the electrode material and the substrate. Due to its excellent conductivity, a metal collector is typically favored. Enhancing the binding strength between the collector and the substrate as well as between the collector and the electrode material has emerged as a critical factor for enhancing the capacitance performance. In this study, a Ag film with a grass root-like structure was initially grown on a PI substrate through the surface modification and ion exchange (SMIE) process. This Ag interlocking structure contributes to strong binding between the PI substrate and Ag without compromising the mechanical properties of the Ag film. To further enhance the electrochemical properties at low scan rates, electroless-plated Cu was subsequently deposited on the Ag film to form the Cu/Ag current collector. Moreover, the Cu within the Cu/Ag current collector served as a precursor for the growth of FeOOH-Cu(OH)2 via a two-step in situ method. The resulting FeOOH-Cu(OH)2/Cu/Ag structure as a whole is binder-free. Supercapacitors employing symmetric FeOOH-Cu(OH)2/Cu/Ag structures were assembled, and their energy storage properties were investigated. The solution-based low-temperature process used in this study offers the potential for cost-effective and large-scale applications.

4.
Dalton Trans ; 52(40): 14564-14572, 2023 Oct 17.
Article in English | MEDLINE | ID: mdl-37782116

ABSTRACT

The Ni-rich layered oxide cathode has shown high energy density, proper rate capability, and longevity of the rechargeable battery, while poor stability and capacity fading are assumed to be its common cons. To address this obstacle, prospective cathode materials are synthesized by integrating the lithium transition metal oxides with an artificial cathode electrolyte interphase (CEI) layer. Herein, plasma-enhanced atomic layer deposition (PEALD) is employed to coat the LiNi0.8Mn0.1Co0.1O2 (NMC811) electrode with Al2O3 and MoO3. The combined results from morphological examinations revealed the formation of uniform Al2O3 and MoO3 sheets after 200 cycles of PEALD coating. Consistent results from the XRD analysis demonstrate that Al2O3 and MoO3 artificial CEIs can reduce Li-Ni mixing. The cyclic voltammetry tests show the oxidation-reduction kinetic. The modified NMC811 structures with Al2O3 and MoO3 represent a remarkable improvement in terms of capacity retention. The coated cathode with Al2O3 clearly outperforms the modified configuration with MoO3 concerning ionic conductivity, charge/discharge reversibility, and capacity retention. The promising results obtained in this study open the possibility of synthesizing Ni-rich cathodes with enhanced electrochemical performance.

5.
ACS Appl Mater Interfaces ; 15(32): 38530-38539, 2023 Aug 16.
Article in English | MEDLINE | ID: mdl-37535433

ABSTRACT

The drastic volume expansion and dendrite growth of lithium metal anodes give rise to poor electrochemical reversibility. Herein, ZnO, N dually doped nanocages (c-ZNCC) were synthesized as the host for lithium metal anodes using the zeolitic imidazolate framework-8 (ZIF-8). The synthesis is based on a two-step core@shell evolution mechanism, which could guide lithium deposition rapidly and offer a fast lithium-ion diffusion during the cycling process. Benefiting from the unique design, the as-obtained c-ZNCC can render a record short lithium infusion as low as 1.5 s, a stable lithium stripping/plating capability as long as 3000 h, and a voltage hysteresis of 95 mV when cycling at 10 mA cm-2 to 10 mA h cm-2. A low Tafel slope of 3.45 mA cm-2 demonstrates the efficient charge transfer of c-ZNCC-Li, and the galvanostatic intermittent titration technique measurement shows high diffusion coefficient of c-ZNCC-Li during the charging process. In addition, the LNMO||c-ZNCC-Li cell exhibits a capacity retention as high as 93.7% at 1 C after 200 cycles. This work creates a new design for deriving nanocages with dual lithiophilic spots using a metal-organic framework and carbon cloth for favorable Li metal anodes.

6.
Folia Microbiol (Praha) ; 67(5): 747-755, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35467317

ABSTRACT

In response to the emergence of drug resistance and limited therapeutic options, researchers are in action to look for more effective and sustainable antimicrobial practices. Over few years, novel nanoparticles are proving to be potent and promising for effectively dealing with ever- evolving microbial pathogens and diseases. In the present investigation, antibacterial and anti-biofilm efficiencies of zinc ferrite nanoparticles (ZnFe2O4 NPs) are explored against opportunistic pathogens Klebsiella pneumoniae (K. pneumoniae). Results of the present study demonstrate that the ZnFe2O4 NPs endow an excellent antibacterial efficiency with a maximum zone of inhibition i.e.16 mm. The reactive oxygen species (ROS)-induced bacterial damage is caused by the ZnFe2O4 NPs. Subsequently, intracellular cytoplasmic leakage of sugar and protein confirms their ability to disturb the membrane integrity of bacteria. This study also demonstrates the prominent efficiency of ZnFe2O4 NPs in an anti-biofilm study by inhibiting biofilm formation up to 81.76% and reducing mature biofilm up to 56.22% at 75 µg/mL the minimum inhibitory concentration value. Therapeutic possibilities of the ZnFe2O4 NPs in antimicrobial applications are discussed which are helpful to overcome the challenges associated with biofilm infectivity.


Subject(s)
Anti-Infective Agents , Nanoparticles , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Anti-Infective Agents/pharmacology , Bacteria/metabolism , Biofilms , Ferric Compounds , Klebsiella pneumoniae , Microbial Sensitivity Tests , Reactive Oxygen Species/metabolism , Sugars/pharmacology , Zinc/pharmacology
7.
Cureus ; 12(1): e6818, 2020 Jan 30.
Article in English | MEDLINE | ID: mdl-32181065

ABSTRACT

Aim To compare the periodontal status in relation to the lower anteriors of patients between labial and lingual orthodontic therapy. Materials and methods The study includes a total of 20 patients in the age group of 20-30 years. All the included patients were selected with limited lower anterior crowding within 0-8 mm. The subjects were randomly divided into two groups: labial (n=10) and lingual (n=10) fixed orthodontic therapy. The periodontal status was evaluated using three indices, plaque index, calculus index, and gingival index, at two different treatment intervals - the first month and the third month - of orthodontic treatment.  Results The values of all the three indices at both time intervals were tabulated. There was no statistical significance when compared to the values in the first month. In the third month, all three indices were statistically significant for both labial and lingual therapy (p<0.001). The lingual appliance had more plaque and calculus accumulation. Conclusion Therefore, the study proves that the lingual surface of patients undergoing lingual orthodontic treatment exhibits more plaque and calculus deposition, thereby the weakening of the periodontal status.

8.
Sensors (Basel) ; 19(9)2019 May 07.
Article in English | MEDLINE | ID: mdl-31067811

ABSTRACT

: Due to advances in technology, research in healthcare using a cyber-physical system (CPS) opens innovative dimensions of services. In this paper, the authors propose an energy- and service-level agreement (SLA)-efficient cyber physical system for E-healthcare during data transmission services. Furthermore, the proposed phenomenon will be enhanced to ensure the security by detecting and eliminating the malicious devices/nodes involved during the communication process through advances in the ad hoc on-demand distance vector (AODV) protocol. The proposed framework addresses the two security threats, such as grey and black holes, that severely affect network services. Furthermore, the proposed framework used to find the different network metrics such as average qualifying service set (QSS) paths, mean hop and energy efficiency of the quickest path. The framework is simulated by calculating the above metrics in mutual cases i.e. without the contribution of malevolent nodes and with the contribution of malevolent nodes over service time, hop count and energy constraints. Further, variation of SLA and energy shows their expediency in the selection of efficient network metrics.

9.
Heliyon ; 4(9): e00801, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30560215

ABSTRACT

Pristine and nanocomposite (NC) hybrid electrodes of polyaniline (PANI)-nickel hydroxide [Ni(OH)2] have been prepared by single and two-step electrodeposition processes, respectively, onto stainless-steel (SS) substrates. Enhanced reversibility and stability of amorphous PANI- Ni(OH)2 NC electrodes compared to single electrode materials have been explored. PANI has a nanofibrous morphology, Ni(OH)2 has nanoplatelet-type morphology, and the NC electrodes retain an overall nanofibrous morphology. The maximum specific capacitance (SC), obtained from integrated charge under voltammetric conditions, for PANI (electro-deposited for 5 min), NC (electrodeposition of Ni(OH)2 for 10 min and 20 min onto PANI electrode surface) and Ni(OH)2 (electrodeposited for 10 min) electrodes, are 0.59, 39.06, 32.36, and 113.8 F/g, respectively, suggesting higher electrochemical performance of Ni(OH)2 electrode compared to PANI and NC electrodes. The retention in SC values with faster scan rates from 10 to 100 mV/s for PANI, NC (10 min), NC (20 min) and Ni(OH)2 are 38.7, 61.1, 52.4, and 29.0 %, respectively, explicitly confirming a higher reversibility in NC electrodes. The retention in SC values with increase of cycle number up to 1000 for PANI, NC (10 min), NC (20 min) and Ni(OH)2 electrodes are 34.9, 61.5, 67.5, and 40.7 % respectively, demonstrating higher electrochemical stability of NC electrodes over pure-phase electrodes. Nearly 2.15, 79.36, 66.66 and 406.83 mC/cm2 charges on PANI, NC (10 min), NC (20 min) and Ni(OH)2 electrodes, respectively, are obtained. Inner to total charge and outer to total charge ratios have been used to explain contributing sites to total charge in pristine and NC electrodes.

10.
Sci Rep ; 7(1): 2524, 2017 05 31.
Article in English | MEDLINE | ID: mdl-28566686

ABSTRACT

The bismuth (Bi3+)-doped cobalt ferrite nanostructures with dual phase, i.e. cubic spinel with space group Fd3m and perovskite with space group R3c, have been successfully engineered via self-ignited sol-gel combustion route. To obtain information about the phase analysis and structural parameters, like lattice constant, Rietveld refinement process is applied. The replacement of divalent Co2+ by trivalent Bi3+ cations have been confirmed from energy dispersive analysis of the ferrite samples. The micro-structural evolution of cobalt ferrite powders at room temperature under various Bi3+ doping levels have been identified from the digital photoimages recorded using scanning electron microscopy. The hyperfine interactions, like isomer shift, quadrupole splitting and magnetic hyperfine fields, and cation distribution are confirmed from the Mossbauer spectra. Saturation magnetization is increased with Bi3+-addition up to x = 0.15 and then is decreased when x = 0.2. The coercivity is increased from 1457 to 2277 G with increasing Bi3+-doping level. The saturation magnetization, coercivity and remanent ratio for x = 0.15 sample is found to be the highest, indicating the potential of Bi3+-doping in enhancing the magnetic properties of cobalt ferrite.

11.
Int J Biol Macromol ; 102: 829-839, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28392387

ABSTRACT

An effort was made to formulate and evaluate pH-sensitive spray dried microspheres using hydrolyzed polyacrylamide-graft-gum karaya (PAAm-g-GK) for colon specific delivery of an anti-cancer agent, capecitabine. The synthesis of pH-sensitive PAAm-g-GK copolymer was done by free radical polymerization followed by alkaline hydrolysis and characterized satisfactorily. The microspheres were spherical in shape; drug entrapment efficiency was found to be in the range of 77.30% to 88.74%. Pulsatile swelling study indicates that the PAAm-g-GK consists of considerable pH-sensitivity. The in-vitro drug release suggested that the microspheres prepared using native GK were incapable to retard the drug release within 5h in the environment of stomach and small intestine. While, those microspheres prepared using pH-sensitive PAAm-g-GK copolymer having crosslinked with glutaraldehyde (GA), released little amount of drug within 5h, but maximum amount of drug was targeted to colonic region in a controlled manner up to 24h. For example, GK10 Microspheres showed only 19.16% drug release at the end of 5th h, while about 80.14% of drug was targeted to colonic region. Cross-linking with GA reduced the early drug release in the upper part of gastrointestinal tract and guaranteed maximum drug release in the colonic region. A rapid enhancement in drug release was witnessed in rat caecal content medium due to the action of colonic bacteria on PAAm-g-GK copolymer.


Subject(s)
Acrylic Resins/chemistry , Antineoplastic Agents/chemistry , Antineoplastic Agents/metabolism , Colon/metabolism , Drug Carriers/chemistry , Karaya Gum/chemistry , Microspheres , Animals , Capecitabine/chemistry , Capecitabine/metabolism , Cecum/metabolism , Drug Liberation , Hydrogen-Ion Concentration , Rats
12.
J Biomater Sci Polym Ed ; 28(2): 139-161, 2017 02.
Article in English | MEDLINE | ID: mdl-27808009

ABSTRACT

Unique pH-sensitive spray dried microspheres were formulated employing hydrolyzed polyacrylamide-g-carboxymethylcellulose sodium (PAAm-g-NaCMC) co-polymer for colon targeted delivery of an anticancer drug, capecitabine. Synthesis of PAAm-g-NaCMC was carried out through free radical polymerization, which was supported with an inert atmosphere and then the alkaline hydrolysis was performed and subjected for characterization including FTIR spectroscopic analysis, 1H NMR spectroscopic analysis, elemental analysis, viscosity measurement, neutralization equivalent and thermo-gravimetric investigation. The swelling data suggested that the PAAm-g-NaCMC possesses significant pH-sensitive property. The microspheres were in the range of 1.00 to 7.34 µ and the drug entrapment efficiency ranged between 70.98 and 94.41%. In vitro drug release suggested the failure of microspheres formulated using native NaCMC which failed to impede drug release in stomach and small intestine, while those prepared with pH-sensitive PAAm-g-NaCMC copolymer and cross-linked with glutaraldehyde are suitable for colon targeting because they retarded release of drug in physiologic atmosphere of stomach and small intestine. Only 12.97% of drug was released from CMC10 formulation by the end of 5th h and rest of drug has been targeted to colonic region. A sudden increase in release of drug was observed in rat caecal contents media because of colonic bacterial action on PAAm-g-NaCMC copolymer.


Subject(s)
Acrylic Resins/chemistry , Antineoplastic Agents/metabolism , Carboxymethylcellulose Sodium/chemistry , Colon/metabolism , Drug Carriers/chemistry , Microspheres , Animals , Capecitabine/chemistry , Capecitabine/metabolism , Drug Liberation , Hydrogen-Ion Concentration , Particle Size , Polymerization , Rats
13.
Dalton Trans ; 45(21): 8845-53, 2016 Jun 07.
Article in English | MEDLINE | ID: mdl-27147084

ABSTRACT

Presently most bacteria are becoming antibiotic resistant. Due to this there is a deficiency of potent antibiotics, therefore we have to preserve and improve the efficiency of existing antibiotics by mitigating the side effects. Enrofloxacin (EFX) is an important antimicrobial used in veterinary practice but it is known to exert immune suppression antioxidant stress. In the present study, we report on: (a) the biosynthesis of selenium nanoparticles (Se NPs), and (b) their protective effect in reducing adverse effects of EFX on broiler chicken. A potent bacterial strain, isolated from farm soil, has been identified as Pantoea agglomerans (GenBank: KU500622). It tolerates a high concentration of selenium dioxide (9 mM) and produces Se NPs under aerobic conditions. The obtained Se NPs are amorphous in structure and spherical in shape with sizes of less than 100 nm. The activity of cellular, humoral immune response and enzymatic and non-enzymatic antioxidants, has significantly been decreased as a result of EFX treatment. We investigated that Se NP supplementation greatly restores these values towards the control, and to even higher than those of the control. Adverse effects of EFX are prevented by simultaneous exposure to Se NPs (0.6 mg per kg of feed) in the diet of poultry chicken.


Subject(s)
Fluoroquinolones/toxicity , Immunity, Cellular/drug effects , Nanoparticles/chemistry , Oxidative Stress/drug effects , Protective Agents/pharmacology , Selenium Oxides/chemistry , Animals , Antioxidants/metabolism , Chickens , Dietary Supplements , Enrofloxacin , Fluoroquinolones/isolation & purification , Immunity, Humoral/drug effects , Nanoparticles/administration & dosage , Nanoparticles/metabolism , Pantoea/metabolism , Particle Size , Phytohemagglutinins/metabolism , Protective Agents/chemistry
14.
J Contemp Dent Pract ; 17(3): 205-10, 2016 Mar 01.
Article in English | MEDLINE | ID: mdl-27207199

ABSTRACT

AIM: The aim of this study was to evaluate the release of nickel and chromium ions in human saliva during fixed orthodontic therapy. MATERIALS AND METHODS: Ten patients with Angle's Class-I malocclusion with bimaxillary protrusion without any metal restorations or crowns and with all the permanent teeth were selected. Five male patients and five female patients in the age group range of 14 to 23 years were scheduled for orthodontic treatment with first premolar extraction. Saliva samples were collected in three stages: sample 1, before orthodontic treatment; sample 2, after 10 days of bonding sample; and sample 3, after 1 month of bonding. The samples were analyzed for the following metals nickel and chromium using inductively coupled plasma optical emission spectrometry (ICP-OES). RESULTS: The levels of nickel and chromium were statistically significant, while nickel showed a gradual increase in the first 10 days and a decline thereafter. Chromium showed a gradual increase and was statistically significant on the 30th day. CONCLUSION: There was greatest release of ions during the first 10 days and a gradual decline thereafter. Control group had traces of nickel and chromium. While comparing levels of nickel in saliva, there was a significant rise from baseline to 10th and 30th-day sample, which was statistically significant. While comparing 10th day to that of 30th day, there was no statistical significance. The levels of chromium ion in the saliva were more in 30th day, and when comparing 10th-day sample with 30th day, there was statistical significance. CLINICAL SIGNIFICANCE: Nickel and chromium levels were well within the permissible levels. However, some hypersensitive individuals may be allergic to this minimal permissible level.


Subject(s)
Chromium/analysis , Nickel/analysis , Orthodontics , Adolescent , Female , Humans , Male , Saliva/chemistry , Time Factors , Young Adult
15.
ACS Comb Sci ; 17(8): 442-51, 2015 Aug 10.
Article in English | MEDLINE | ID: mdl-26161720

ABSTRACT

A sequential single-flask multicomponent reactions is highly effective for the synthesis of 1,2-dihydroisoquinolines through amidealkylation from intermediate N-acylisoquinolinium salts under mild conditions. N-Acylisoquinolinium ions and trichloromethyl-1-(1H-indol-3-yl)isoquinoline-2(1H)-carboxylate have demonstrated their reactivity toward aromatic and aliphatic π-nucleophiles. One of the 1,2-dihydroisoquinoline derivatives was found to be a potent inhibitor for transcription factor NF-κB by blocking IκBα degradation, p65 nuclear translocation, and NF-κB DNA binding in TNF-α-induced NIH 3T3 cells.


Subject(s)
Isoquinolines/chemical synthesis , Isoquinolines/pharmacology , NF-kappa B/antagonists & inhibitors , Animals , Cells, Cultured , Humans , Isoquinolines/chemistry , Mice , Molecular Structure , NF-kappa B/metabolism , NIH 3T3 Cells , Structure-Activity Relationship , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Tumor Necrosis Factor-alpha/metabolism
16.
Indian J Cancer ; 51(4): 418-9, 2014.
Article in English | MEDLINE | ID: mdl-26842144

ABSTRACT

BACKGROUND: There is paucity of data on the epidemiology of bloodstream infections in pediatric cancer patients from India. Rationale use of antibiotics in febrile neutropenia is important for reducing morbidity and preventing the emergence of drug resistant bacteria. AIMS: The study was conducted to look at the prevalence of bloodstream bacterial infection and the antibiotic resistance profile at Cancer Institute, Chennai. SETTINGS AND DESIGN: This was a retrospective study. MATERIALS AND METHODS: Data on all blood cultures taken from pediatric cancer patients treated at Cancer Institute, Chennai, during the year 2013 were analyzed. The microbiological profile and sensitivity pattern were analyzed. RESULTS: A total of 1045 blood culture samples were taken, and there were 82/1045 (7.5%) positive blood cultures. Gram-negative organisms accounted for 50/82 (61%) of all positive cultures. Klebsiella pneumoniae (32%) was the most common Gram-negative isolate, and Staphylococcus aureus (93.5%) was the most common Gram-positive. There was high resistance to aminoglycosides and beta-lactam/beta-lactamase inhibitor antibodies. CONCLUSION: Gram-negative organisms are the predominant bacteria isolated. There is high resistance to first-line combination antibiotics used as empiric therapy for treatment of febrile neutropenia.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteremia/epidemiology , Drug Resistance, Bacterial , Febrile Neutropenia/complications , Gram-Negative Bacterial Infections/epidemiology , Gram-Positive Bacterial Infections/epidemiology , Neoplasms/therapy , Adolescent , Bacteremia/microbiology , Cancer Care Facilities , Child , Child, Preschool , Gram-Negative Bacterial Infections/complications , Gram-Negative Bacterial Infections/microbiology , Gram-Positive Bacterial Infections/complications , Gram-Positive Bacterial Infections/microbiology , Humans , India , Infant , Infant, Newborn , Neoplasms/complications , Prevalence , Retrospective Studies
17.
Dalton Trans ; 42(36): 13065-70, 2013 Sep 28.
Article in English | MEDLINE | ID: mdl-23873500

ABSTRACT

Photoelectrochemical cells (PECs) of ZnO/CdSe decorated with a charge separating SnO2 nanoparticles (NPs) layer of various thicknesses are prepared and characterized by using scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), UV-visible absorption, energy dispersive X-ray analysis spectroscopy (EDX) and incident photon-to-current conversion efficiency (IPCE) measurements. A uniform coverage of the SnO2 NPs layer over ZnO/CdSe electrode surface is evidenced. The EDX elemental mapping analysis of the ZnO/CdSe/SnO2 PECs demonstrates the presence of Sn and O over the surface. A remarkable improvement in the light harvesting efficiency confirmed from the IPCE measurement, supports an enhancement in current density in the current density-voltage measurement due to increased electron transport and smaller charge recombination. Moreover, these observations are corroborated with the EIS measurement as a cell with SnO2 reveals a reduced charge transfer resistance due to which the power conversion efficiency is increased from 2.20 to 3.41% i.e. 55% compared to the pristine ZnO/CdSe PEC.

18.
Prostate Int ; 1(4): 163-8, 2013.
Article in English | MEDLINE | ID: mdl-24392441

ABSTRACT

PURPOSE: To compare the cancer detection rate in patients with raised serum prostate-specific antigen (PSA) or abnormal digital rectal examination (DRE) results between the 10-core and the 16-core biopsy techniques in an Indian population. METHODS: Between November 2010 and November 2012, 95 men aged >50 years who presented to the Urology Department with lower urinary tract symptoms, elevated serum PSA, and/or abnormal DRE findings underwent transrectal ultrasonography (TRUS)-guided prostate biopsy. A total of 53 patients underwent 10-core biopsy and 42 patients underwent 16-core biopsy. RESULTS: Of the 53 men in the 10-core group, 8 had cancer, whereas in the 16-core biopsy group, 23 of 42 men had cancer. Detection of prostate cancer was significantly higher in patients who underwent 16-core biopsy than in those who underwent 10-core biopsy (P<0.001). Among the 95 men, 44 men had abnormal DRE findings (46.3%), of whom 23 showed cancer (52.27%). Of 51 men with normal DRE findings and elevated PSA, 8 men had malignancy with a cancer detection rate of 15.68%. Among 20 men with PSA between 4.1 and 10 ng/mL, 2 (10%) had cancer. In 31 men with PSA between 10.1 and 20 ng/mL, 3 cancers (9.67%) were detected, and in 44 men with PSA >20 ng/mL, 26 cancers were detected (59.09%). CONCLUSIONS: The cancer detection rate with 16-core TRUS-guided biopsy is significantly higher than that with 10-core biopsy (54.76% vs. 15.09%, P<0.001). In patients with both normal and abnormal DRE findings, 16-core biopsy has a better detection rate than the 10-core biopsy protocol. With increasing PSA, there is a high rate of detection of prostate cancer in both 10-core and 16-core biopsy patients.

19.
Org Lett ; 11(24): 5586-9, 2009 Dec 17.
Article in English | MEDLINE | ID: mdl-19928999

ABSTRACT

An efficient C-C bond formation reaction assisted by a fluoride ion has been identified for N,N'-diphenyl-1,4-phenylenediimine with the compounds having an active methylene group. The reaction follows the typical Michael addition fashion and proceeds to completion within 1 h at 70 degrees C in acetonitrile in the presence of tetrabutylammonium fluoride (TBAF), while the same reaction failed to proceed in the absence of a fluoride anion. The new finding reported herein also offers an unprecedented method for a direct functionalization of polyaniline backbone with versatile functional alkyl groups.

20.
Chem Pharm Bull (Tokyo) ; 57(10): 1174-7, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19801885

ABSTRACT

Raloxifene HCl (RHCl) is known to be susceptible to oxidation and forms the corresponding N-oxide derivative as the primary degradation product. The purpose of this study was to evaluate the role of excipients on the generation of the N-oxide derivative from the corresponding RHCl-excipient binary mixtures. Binary mixtures of RHCl with crospovidone, povidone, magnesium stearate, Tween 80 and anhydrous lactose in drug: excipients ratio of 1:1 (crospovidone and povidone); 10:1 (Tween 80 and magnesium stearate) and 1:5 (anhydrous lactose) were prepared by both dry blending (trituration) and wet blending (to improve contact between drug and excipients). The prepared binary mixtures were then stored at 25, 40, 75 and 125 degrees C and generation of the N-oxide derivative was monitored over six months using a validated HPLC method. Pure drug and excipients stored similarly acted as controls. Further, all the individual excipients (used as control) were monitored for peroxide impurity generation using an in-house colorimetric method. The results showed that N-oxide generation was observed from all binary mixtures and the amount of N-oxide derivative formed were always higher from the mixtures prepared by wet blending and the amount of N-oxide derivative formed was dependent on storage temperature. This study thus shows that the presence of peroxide in the excipient and its role in oxidative degradation of drug substance calls for monitoring of the peroxide impurity present in the excipients used for formulating of drug sensitive to oxidation as used herein.


Subject(s)
Excipients/chemistry , Oxides/chemistry , Raloxifene Hydrochloride/chemistry , Oxidation-Reduction , Oxides/chemical synthesis , Temperature , Time Factors
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