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Fulltext Temporal regulation of proteome profile in the fruit fly, Drosophila melanogaster

Subramanian P, Jayapalan JJ, Abdul-Rahman PS, Arumugam M, Hashim OH

PeerJ, 2016;4:e2080.
PMID: 27257555 DOI: 10.7717/peerj.2080

Background. Diurnal rhythms of protein synthesis controlled by the biological clock underlie the rhythmic physiology in the fruit fly, Drosophila melanogaster. In this study, we conducted a proteome-wide investigation of rhythmic protein accumulation in D. melanogaster. Materials and Methods. Total protein collected from fly samples harvested at 4 h intervals over the 24 h period were subjected to two-dimensional gel electrophoresis, trypsin digestion and MS/MS analysis. Protein spots/clusters were identified with MASCOT search engine and Swiss-Prot database. Expression of proteins was documented as percentage of volume contribution using the Image Master 2D Platinum software. Results. A total of 124 protein spots/clusters were identified using MS/MS analysis. Significant variation in the expression of 88 proteins over the 24-h period was observed. A relatively higher number of proteins was upregulated during the night compared to the daytime. The complexity of temporal regulation of the D. melanogaster proteome was further reflected from functional annotations of the differently expressed proteins, with those that were upregulated at night being restricted to the heat shock proteins and proteins involved in metabolism, muscle activity, protein synthesis/folding/degradation and apoptosis, whilst those that were overexpressed in the daytime were apparently involved in metabolism, muscle activity, ion-channel/cellular transport, protein synthesis/folding/degradation, redox homeostasis, development and transcription. Conclusion. Our data suggests that a wide range of proteins synthesized by the fruit fly, D. melanogaster, is under the regulation of the biological clock.

Matched MeSH terms: Platinum
Voltammetric sensing of formaldehyde by using a nanocomposite prepared by reductive deposition of palladium and platinum on polypyrrole-coated nitrogen-doped reduced graphene oxide

Mahmoudian MR, Basirun WJ, Woi PM, Hazarkhani H, Alias YB

Mikrochim Acta, 2019 05 22;186(6):369.
PMID: 31119482 DOI: 10.1007/s00604-019-3481-y

The study presents the synthesis of polypyrrole-coated palladium platinum/nitrogen-doped reduced graphene oxide nanocomposites (PdPt-PPy/N-rGO NC) via direct the reduction of Pd(II) and Pt(II) in the presence of pyrrole monomer, N-rGO and L-cysteine as the reducing agent. X-ray diffraction confirmed the presence of metallic Pd and Pt from the reduction of Pd and Pt cations. Transmission electron microscopy images revealed the presence of Pd, Pt and PPy deposition on N-rGO. Impedance spectroscopy results gave a decreased charge transfer resistance due to the presence of N-rGO. The nanocomposites were synthesized with different Pd/Pt ratios (2:1, 1:1 and 1:2). A glassy carbon electrode (GCE) modified with the nanocomposite showed enhanced electrochemical sensing capability for formaldehyde in 0.1 M sulfuric acid solution. Cyclic voltammetry showed an increase in the formaldehyde oxidation peak current at the GCE modified with Pd2Pt1 PPy N-rGO. At a typical potential of 0.45 V (vs. SCE), the sensitivity in the linear segment was 345.8 μA.mM -1. cm-2. The voltammetric response was linear between 0.01 and 0.9 mM formaldehyde concentration range, with a 27 µM detection limit (at S/N = 3). Graphical abstract Schematic presentation of formaldehyde detection by Pd2Pt1-PPy/nitrogen-doped reduced Graphene Oxide Nanocomposite (Pd2Pt1-PPy /N-Gr NC). The decrease of charge transfer resistance and the agglomeration of deposited metals in the presence of N-rGO enhance the current response of the electrochemical sensor.

Matched MeSH terms: Platinum
Schiff base-nickel, palladium, and platinum complexes derived from N-cyclohexyl hydrazine carbothioamide and 3-hydroxy-4-methoxybenzaldehyde: Selective antiproliferative and proapoptotic effects against colorectal carcinoma

Arafath MA, Al-Suede FSR, Adam F, Al-Juaid S, Khadeer Ahamed MB, Majid AMSA

Drug Dev Res, 2019 09;80(6):778-790.
PMID: 31215682 DOI: 10.1002/ddr.21559

The bidentate N-cyclohexyl-2-(3-hydroxy-4-methoxybenzylidene)hydrazine-1-carbothioamide Schiff base ligand (HL) was coordinated to divalent nickel, palladium and platinum ions to form square planar complexes. The nickel and palladium complexes, [NiL2 ], [PdL2 ] form square planar complexes with 2:1 ligand to metal ratio. The platinum complex, [PtL(dmso)Cl] formed a square planar complex with 1:1 ligand to metal ratio. Platinum undergoes in situ reaction with DMSO before complexing with the ligand in solution. The cytotoxicity of HL, [NiL2 ], [PdL2 ], and [PtL(dmso)Cl] were evaluated against human colon cancer cell line (HCT-116), human cervical cancer (Hela) cell line, melanoma (B16F10) cells, and human normal endothelial cell lines (Eahy926) by MTT assay. The [NiL2 ] complex displayed selective cytotoxic effect against the HCT 116 cancer cell line with IC50 of 7.9 ± 0.2 μM. However, HL, [PdL2 ], and [PtL(dmso)Cl] only exhibited moderate cytotoxic activity with IC50 = 75.9 ± 2.4, 100.0 ± 1.8, and 101.0 ± 3.6 μM, respectively. The potent cytotoxicity of [NiL2 ] was characterized using Hoechst and Rhodamine assays. The nickel complex, [NiL2 ], caused remarkable nuclear condensation and reduction in mitochondrial membrane potential. In addition, molecular docking studies confirms that [NiL2 ] possesses significant binding efficiency with Tyrosine kinase. Altogether, the results revealed that [NiL2 ] exhibits cytotoxicity against the cancer cells via Tyrosine kinase-induced proapoptosis pathway. This study demonstrates that the [NiL2 ] complex could be a promising therapeutic agent against colorectal carcinoma.

Matched MeSH terms: Platinum/chemistry*
Development of an implantable D-serine biosensor for in vivo monitoring using mammalian D-amino acid oxidase on a poly (o-phenylenediamine) and Nafion-modified platinum-iridium disk electrode

Zain ZM, O'Neill RD, Lowry JP, Pierce KW, Tricklebank M, Dewa A, et al.

Biosens Bioelectron, 2010 Feb 15;25(6):1454-9.
PMID: 19945264 DOI: 10.1016/j.bios.2009.10.049

D-serine has been implicated as a brain messenger, promoting not only neuronal signalling but also synaptic plasticity. Thus, a sensitive tool for D-serine monitoring in brain is required to understand the mechanisms of D-serine release from glia cells. A biosensor for direct fixed potential amperometric monitoring of D-serine incorporating mammalian D-amino acid oxidase (DAAO) immobilized on a Nafion coated poly-ortho-phenylenediamine (PPD) modified Pt-Ir disk electrode was therefore developed. The combined layers of PPD and Nafion enhanced the enzyme activity and biosensor efficiency by approximately 2-fold compared with each individual layer. A steady state response time (t(90%)) of 0.7+/-0.1s (n=8) and limit of detection 20+/-1 nM (n=8) were obtained. Cylindrical geometry showed lower sensitivity compared to disk geometry (61+/-7 microA cm(-2) mM(-1), (n=4), R(2)=0.999). Interference by ascorbic acid (AA), the main interference species in the central nervous system and other neurochemical electroactive molecules was negligible. Implantation of the electrode and microinjection of D-serine into rat brain striatal extracellular fluid demonstrated that the electrode was capable of detecting D-serine in brain tissue in vivo.

Matched MeSH terms: Platinum/chemistry
Fulltext Oxidative stress cytotoxicity induced by platinum-doped magnesia nanoparticles in cancer cells

Al-Fahdawi MQ, Al-Doghachi FAJ, Abdullah QK, Hammad RT, Rasedee A, Ibrahim WN, et al.

Biomed Pharmacother, 2021 Jun;138:111483.
PMID: 33744756 DOI: 10.1016/j.biopha.2021.111483

The aim of this study was to prepare, characterize, and determine the in vitro anticancer effects of platinum-doped magnesia (Pt/MgO) nanoparticles. The chemical compositions, functional groups, and size of nanoparticles were determined using X-ray diffraction, Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, and scanning electron microscopy. Pt/MgO nanoparticles were cuboid and in the nanosize range of 30-50 nm. The cytotoxicity of Pt/MgO nanoparticles was determined via the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on the human lung and colonic cancer cells (A549 and HT29 respectively) and normal human lung and colonic fibroblasts cells (MRC-5 and CCD-18Co repectively). The Pt/MgO nanoparticles were relatively innocuous to normal cells. Pt/MgO nanoparticles downregulated Bcl-2 and upregulated Bax and p53 tumor suppressor proteins in the cancer cells. Pt/MgO nanoparticles also induced production of reactive oxygen species, decreased cellular glutathione level, and increased lipid peroxidation. Thus, the anticancer effects of Pt/MgO nanoparticles were attributed to the induction of oxidative stress and apoptosis. The study showed the potential of Pt/MgO nanoparticles as an anti-cancer compound.

Matched MeSH terms: Platinum/toxicity*
Low electric field DNA separation and in-channel amperometric detection by microchip capillary electrophoresis

Ghanim MH, Najimudin N, Ibrahim K, Abdullah MZ

IET Nanobiotechnol, 2014 Jun;8(2):77-82.
PMID: 25014078 DOI: 10.1049/iet-nbt.2012.0044

Miniaturisation of microchip capillary electrophoresis (MCE) is becoming an increasingly important research topic, particularly in areas related to micro total analysis systems or lab on a chip. One of the important features associated with the miniaturised MCE system is the portable power supply unit. In this work, a very low electric field MCE utilising an amperometric detection scheme was designed for use in DNA separation. The device was fabricated from a glass/polydimethylsiloxane hybrid engraved microchannel with platinum electrodes sputtered onto a glass substrate. Measurement was based on a three-electrode arrangement, and separation was achieved using a very low electric field of 12 V/cm and sample volume of 1.5 µl. The device was tested using two commercial DNA markers of different base pair sizes. The results are in agreement with conventional electrophoresis, but with improved resolution. The sensitivity consistently higher than 100 nA, and the separation time approximately 45 min, making this microchip an ideal tool for DNA analysis.

Matched MeSH terms: Platinum/chemistry
Fulltext Significant Broadband Photocurrent Enhancement by Au-CZTS Core-Shell Nanostructured Photocathodes

Zhang X, Wu X, Centeno A, Ryan MP, Alford NM, Riley DJ, et al.

Sci Rep, 2016;6:23364.
PMID: 26997140 DOI: 10.1038/srep23364

Copper zinc tin sulfide (CZTS) is a promising material for harvesting solar energy due to its abundance and non-toxicity. However, its poor performance hinders their wide application. In this paper gold (Au) nanoparticles are successfully incorporated into CZTS to form Au@CZTS core-shell nanostructures. The photocathode of Au@CZTS nanostructures exhibits enhanced optical absorption characteristics and improved incident photon-to-current efficiency (IPCE) performance. It is demonstrated that using this photocathode there is a significant increase of the power conversion efficiency (PCE) of a photoelectrochemical solar cell of 100% compared to using a CZTS without Au core. More importantly, the PCE of Au@CZTS photocathode improved by 15.8% compared to standard platinum (Pt) counter electrode. The increased efficiency is attributed to plasmon resonance energy transfer (PRET) between the Au nanoparticle core and the CZTS shell at wavelengths shorter than the localized surface plasmon resonance (LSPR) peak of the Au and the semiconductor bandgap.

Matched MeSH terms: Platinum
Fulltext Comparative evaluation of apical bacterial extrusion following root canal instrumentation using different endodontic file systems: An in vitro study

Vankayala B, Anantula K, Saladi H, Gudugunta L, Basavarajaiah JM, Yadav SS

J Conserv Dent, 2020 08 20;22(6):559-563.
PMID: 33088065 DOI: 10.4103/JCD.JCD_221_19

Aim: This study aims to evaluate the amount of apical extrusion of bacteria during root canal instrumentation using K3XF, Protaper Gold, Edge taper platinum, and Hyflex CM Rotary systems.
Materials and Methods: Sixty freshly extracted maxillary incisors teeth collected in saline. Access cavity prepared and canals were made free of bacterial and pulp. The teeth were mounted on the bacteria collecting apparatus. Root canals were contaminated with the Fusobacterium Nucleatum (ATCC25586) and dried at 37°C for 24 h. In Group 1 (Control group): No instrumentation was done and biomechanical preparation done in all other groups with Group 2: Hand K-files, Group 3: Protaper gold, Group 4: K3XF, Group 5: Edge taper platinum, and Group 6: Hyflex CM rotary file systems. Then, the extrude was collected, and it is incubated in Mueller-Hinton agar for 24 h and the number of colony forming units were counted and statistical comparison was done using Kruskal-Wallis test and Mann-Whitney U test.
Results: Hand K-files extruded more bacteria when compared to other four rotary systems, K3XF file system extruded least number of bacteria.
Conclusion: All instrumentation techniques extruded intracanal bacteria apically. However, engine-driven nickel-titanium instruments extruded less bacteria than the manual technique. The K3XF rotary file system comparatively extruded less bacteria than other rotary file systems.

Matched MeSH terms: Platinum
Fulltext Intraperitoneal chemotherapy following refractory intravenous route in advanced ovarian cancer

Shafiee, M.N., Omar, M.H., Suraya, A., Hatta, M.

Journal of Surgical Academia, 2013;3(1):28-31.
MyJurnal

Platinum based adjuvant chemotherapy is generally recommended for ovarian cancer to improve the survival rate. Intravenous route is commonly used, easily administered and less associated complications. However, intraperitoneal route is gaining its popularity as a single procedure or adjunctive to the intravenous route. Numerous questions on its eligibility and safety are still perplexed. A case review on a patient with non optimal debulking surgery of advanced ovarian cancer was studied. Intravenous platinum based chemotherapy combined with paclitaxel failed to bring her to clinical remission. Second line chemotherapy, gemcitabin rendered her to poor response with unresolved debilitating ascites needing recurrent drainage. Surprisingly, a trial of intraperitoneal chemotherapy with cisplatin revealed a great response with a complete clinical remission.

Matched MeSH terms: Platinum
Fulltext A successful case of endovascular treatment (EVT) of anterior communicating artery aneurysm associated with moyamoya disease

Sobri, M.A., Noorakmal, A., Razali, R.

Malaysian Journal of Medicine and Health Sciences, 2012;8(1):73-76.
MyJurnal

Saccular aneurysms associated with moyamoya disease are commonly located in the vertebrobasilar circulation. Anterior circulation aneurysm associated with moyamoya disease is uncommon and is usually treated by neurosurgical clipping. Objective: We report a succesful treatment using the endovascular approach in a case of ruptured anterior communicating artery aneurysm in unilateral moyamoya disease. Clinical Presentation: A 23 year old man presented with a 5 day history of headache, diplopia and fever. Computed Tomography (CT) scan and cerebral angiogram showed a bilobed anterior comunicating artery aneurysm. There was also severe M1 segment stenosis of the left middle cerebral artery with multiple collaterals, representing moyamoya vessels. Intervention: Treatment was done under general anesthesia and followed the standard practice for endovascular treatment. The aneurysm was occluded with three detachable platinum microcoils (Microplex®, Microvention®). Conclusion: Endovascular treatment can be a treatment option for ruptured anterior circulation saccular aneurysms associated with moyamoya disease.

Matched MeSH terms: Platinum
Fulltext Vestibulotoxicity Associated With Platinum-Based Chemotherapy in Survivors of Cancer: A Scoping Review

Prayuenyong P, Taylor JA, Pearson SE, Gomez R, Patel PM, Hall DA, et al.

Front Oncol, 2018;8:363.
PMID: 30319960 DOI: 10.3389/fonc.2018.00363

Background: Cochleotoxicity following the treatment with platinum-based chemotherapy is well documented. The potential for vestibulotoxicity is still unclear. This scoping review examined the extent of current research literature, summarized research findings and identified research gaps regarding vestibular-related adverse effects associated with platinum-based chemotherapy in survivors of cancer. Methods: Inclusion criteria followed the PICO principles: Participants, adult, and pediatric cancer patients of any cancer type; Intervention, platinum-based chemotherapy (such as cisplatin, carboplatin, and oxaliplatin); Control, none or any; Outcomes, vestibular-related adverse effects. English language articles published since 1978 were retrieved. Seventy-five eligible studies were identified from a systematic literature search, and relevant data were charted, collated, and summarized. Results: Testing for vestibulotoxicity predominately featured functional evaluation of the horizontal semicircular canal using the caloric and rotational tests. The rate of abnormal vestibular function test results after chemotherapy administration varied from 0 to 50%. The results of objective testing did not always correspond to patient symptoms. There is tentative support for patients with pre-existing loss of vestibular function to be more likely to experience vestibular toxicity after dosing with cisplatin. Conclusions: A number of studies reported significant evidence of vestibular toxicities associated with platinum-based chemotherapy, especially cisplatin. This scoping review emphasizes that vestibular toxicity needs more attention and comprehensive evaluation. Specifically, studies that analyse cumulative dose of platinum-based chemotherapy, affected sites of lesion in vestibular end organs, and the correlation and temporal patterns of cochlear and vestibular toxicity are needed.

Matched MeSH terms: Organoplatinum Compounds; Platinum
Fulltext InSitu Anodization of WO₃-Decorated TiO₂ Nanotube Arrays for Efficient Mercury Removal

Lee WH, Lai CW, Hamid SBA

Materials (Basel), 2015 Aug 28;8(9):5702-5714.
PMID: 28793530 DOI: 10.3390/ma8095270

WO₃-decorated TiO₂ nanotube arrays were successfully synthesized using an in situ anodization method in ethylene glycol electrolyte with dissolved H₂O₂ and ammonium fluoride in amounts ranging from 0 to 0.5 wt %. Anodization was carried out at a voltage of 40 V for a duration of 60 min. By using the less stable tungsten as the cathode material instead of the conventionally used platinum electrode, tungsten will form dissolved ions (W(6+)) in the electrolyte which will then move toward the titanium foil and form a coherent deposit on the titanium foil. The fluoride ion content was controlled to determine the optimum chemical dissolution rate of TiO₂ during anodization to produce a uniform nanotubular structure of TiO₂ film. Nanotube arrays were then characterized using FESEM, EDAX, XRD, as well as Raman spectroscopy. Based on the FESEM images obtained, nanotube arrays with an average pore diameter of up to 65 nm and a length of 1.8 µm were produced. The tungsten element in the samples was confirmed by EDAX results which showed varying tungsten content from 0.22 to 2.30 at%. XRD and Raman results showed the anatase phase of TiO₂ after calcination at 400 °C for 4 h in air atmosphere. The mercury removal efficiency of the nanotube arrays was investigated by photoirradiating samples dipped in mercury chloride solution with TUV (Tube ultraviolet) 96W UV-B Germicidal light. The nanotubes with the highest aspect ratio (15.9) and geometric surface area factor (92.0) exhibited the best mercury removal performance due to a larger active surface area, which enables more Hg(2+) to adsorb onto the catalyst surface to undergo reduction to Hg⁰. The incorporation of WO₃ species onto TiO₂ nanotubes also improved the mercury removal performance due to improved charge separation and decreased charge carrier recombination because of the charge transfer from the conduction band of TiO₂ to the conduction band of WO₃.

Matched MeSH terms: Platinum
Role of dissolved oxygen on the degradation mechanism of Reactive Green 19 and electricity generation in photocatalytic fuel cell

Lee SL, Ho LN, Ong SA, Wong YS, Voon CH, Khalik WF, et al.

Chemosphere, 2018 Mar;194:675-681.
PMID: 29247929 DOI: 10.1016/j.chemosphere.2017.11.166

In this study, a membraneless photocatalytic fuel cell with zinc oxide loaded carbon photoanode and platinum loaded carbon cathode was constructed to investigate the impact of dissolved oxygen on the mechanism of dye degradation and electricity generation of photocatalytic fuel cell. The photocatalytic fuel cell with high and low aeration rate, no aeration and nitrogen purged were investigated, respectively. The degradation rate of diazo dye Reactive Green 19 and the electricity generation was enhanced in photocatalytic fuel cell with higher dissolved oxygen concentration. However, the photocatalytic fuel cell was still able to perform 37% of decolorization in a slow rate (k = 0.033 h-1) under extremely low dissolved oxygen concentration (approximately 0.2 mg L-1) when nitrogen gas was introduced into the fuel cell throughout the 8 h. However, the change of the UV-Vis spectrum indicates that the intermediates of the dye could not be mineralized under insufficient dissolved oxygen level. In the aspect of electricity generation, the maximum short circuit current (0.0041 mA cm-2) and power density (0.00028 mW cm-2) of the air purged photocatalytic fuel cell was obviously higher than that with nitrogen purging (0.0015 mA cm-2and 0.00008 mW cm-2).

Matched MeSH terms: Platinum
Fulltext Biogenic platinum from agricultural wastes extract for improved methanol oxidation reaction in direct methanol fuel cell

Ishak NAIM, Kamarudin SK, Timmiati SN, Karim NA, Basri S

J Adv Res, 2021 Feb;28:63-75.
PMID: 33364046 DOI: 10.1016/j.jare.2020.06.025

Platinum is the most commonly used catalyst in fuel cell application. However, platinum is very expensive, thus limits the commercialisation of fuel cell system due to the cost factor. This study introduces a biosynthesis platinum from plant extracts that can reduce the cost of platinum production compared to the conventional method and the hazardous during the production of the catalyst. The biogenic platinum was tested on a Direct Methanol Fuel Cell. Advanced biogenic of Pt nano-cluster was synthesized through a novel and facile of one-pot synthesis bio-reduction derived from natural source in the form of plant extracts as reducing agent. Several selected plant extracts drawn from agricultural waste such as banana peel, pineapple peels and sugarcane bagasse extracts were comparatively evaluated on the ability of phytochemical sources of polyphenols rich for the development of single-step synthesis for Pt NPs. Notably, the biogenic Pt NPs from sugar cane bagasse has superior electro-catalytic activity, the enhanced utilization efficiency of Pt and appreciable stability towards methanol oxidation reaction, whose ECSA value approximates 94.58 m2g-1, mass activity/specific activity (398.20 mAmg-1/0.8471 mA/cm2Pt) which greater than commercial Pt black (158.12 mAmg-1/1.41 mA/cm2Pt).

Matched MeSH terms: Platinum
Fulltext Combining PARP Inhibition with Platinum, Ruthenium or Gold Complexes for Cancer Therapy

Yusoh NA, Ahmad H, Gill MR

ChemMedChem, 2020 Nov 18;15(22):2121-2135.
PMID: 32812709 DOI: 10.1002/cmdc.202000391

Platinum drugs are heavily used first-line chemotherapeutic agents for many solid tumours and have stimulated substantial interest in the biological activity of DNA-binding metal complexes. These complexes generate DNA lesions which trigger the activation of DNA damage response (DDR) pathways that are essential to maintain genomic integrity. Cancer cells exploit this intrinsic DNA repair network to counteract many types of chemotherapies. Now, advances in the molecular biology of cancer has paved the way for the combination of DDR inhibitors such as poly (ADP-ribose) polymerase (PARP) inhibitors (PARPi) and agents that induce high levels of DNA replication stress or single-strand break damage for synergistic cancer cell killing. In this review, we summarise early-stage, preclinical and clinical findings exploring platinum and emerging ruthenium anti-cancer complexes alongside PARPi in combination therapy for cancer and also describe emerging work on the ability of ruthenium and gold complexes to directly inhibit PARP activity.

Matched MeSH terms: Platinum/pharmacology; Platinum/chemistry
Fulltext SnO2/Pt thin film laser ablated gas sensor array

Shahrokh Abadi MH, Hamidon MN, Shaari AH, Abdullah N, Wagiran R

Sensors (Basel), 2011;11(8):7724-35.
PMID: 22164041 DOI: 10.3390/s110807724

A gas sensor array was developed in a 10 × 10 mm(2) space using Screen Printing and Pulse Laser Ablation Deposition (PLAD) techniques. Heater, electrode, and an insulator interlayer were printed using the screen printing method on an alumina substrate, while tin oxide and platinum films, as sensing and catalyst layers, were deposited on the electrode at room temperature using the PLAD method, respectively. To ablate SnO(2) and Pt targets, depositions were achieved by using a 1,064 nm Nd-YAG laser, with a power of 0.7 J/s, at different deposition times of 2, 5 and 10 min, in an atmosphere containing 0.04 mbar (4 kPa) of O(2). A range of spectroscopic diffraction and real space imaging techniques, SEM, EDX, XRD, and AFM were used in order to characterize the surface morphology, structure, and composition of the films. Measurement on the array shows sensitivity to some solvent and wood smoke can be achieved with short response and recovery times.

Matched MeSH terms: Platinum/chemistry
Substrate effects on surface morphologies and magnetic properties of nanostructured FePt thin films

Low PL, Yong BE, Ong BH, Matsumoto M, Tou TY

J Nanosci Nanotechnol, 2011 Mar;11(3):2640-3.
PMID: 21449444

The substrate effects on surface morphologies, crystal structures, and magnetic properties of the sputter-deposited FePt thin films on Corning 1737, normal glass, and Si wafer substrates, respectively, were investigated. High in-plane coercivities of 10 kOe were obtained for the air-annealed films on Corning 1737 and Si wafer, where both films similarly have granular-like morphologies. Besides, increasing grain size and surface roughness of all the FePt films with the post-anneal temperature were observed. Moreover, partially separated grains were seen in the film on Si wafer, where the formation of Fe silicides during post-anneal is suspected, in which has enhanced the magnetic ordering.

Matched MeSH terms: Platinum/chemistry*
The effect of oleic acid stabilizer on the surface properties of bimetallic PtNi catalysts

Abu Bakar NH, Abu Bakar M, Bettahar MM, Ismail J, Monteverdi S

J Nanosci Nanotechnol, 2013 Jul;13(7):5034-43.
PMID: 23901527

A detailed study on the surface properties of oleic acid-stabilized PtNi nanoparticles supported on silica is reported. The oleic acid-stabilized PtNi nanoparticles were synthesized using NaBH4 as the reducing agent at various temperatures and oleic acid concentrations, prior to incorporation onto the silica support. X-ray diffraction studies of the unsupported oleic acid-stabilized PtNi particles revealed that the PtNi existed as alloys. Upon incorporation onto silica support, surface properties of the catalysts were investigated using H2-temperature reduction (H2-TPR), H2-temperature desorption (H2-TPD) and H2-chemisorption techniques. It was found that for the bimetallic catalysts, no oxides or very little oxidation occurred. Furthermore, these catalysts exhibited both Pt and Ni active sites on its surface though the availability of Ni active sites was dominant. A comparison of the surface properties of these materials with those prepared without oleic acid in our previous work [N. H. H. Abu Bakar et al., J. Catal. 265, 63 (2009)] and how they affect the hydrogenation of benzene is also discussed.

Matched MeSH terms: Platinum/chemistry*
Genetic polymorphisms as potential pharmacogenetic biomarkers for platinum-based chemotherapy in non-small cell lung cancer

Sito H, Tan SC

Mol Biol Rep, 2024 Jan 13;51(1):102.
PMID: 38217759 DOI: 10.1007/s11033-023-08915-2

Platinum-based chemotherapy (PBC) is a widely used treatment for various solid tumors, including non-small cell lung cancer (NSCLC). However, its efficacy is often compromised by the emergence of drug resistance in patients. There is growing evidence that genetic variations may influence the susceptibility of NSCLC patients to develop resistance to PBC. Here, we provide a comprehensive overview of the mechanisms underlying platinum drug resistance and highlight the important role that genetic polymorphisms play in this process. This paper discussed the genetic variants that regulate DNA repair, cellular movement, drug transport, metabolic processing, and immune response, with a focus on their effects on response to PBC. The potential applications of these genetic polymorphisms as predictive indicators in clinical practice are explored, as are the challenges associated with their implementation.

Matched MeSH terms: Platinum/therapeutic use
Fulltext Development of a hydrogen gas sensor using a double SAW resonator system at room temperature

Yunusa Z, Hamidon MN, Ismail A, Mohd Isa M, Yaacob MH, Rahmanian S, et al.

Sensors (Basel), 2015;15(3):4749-65.
PMID: 25730480 DOI: 10.3390/s150304749

A double SAW resonator system was developed as a novel method for gas sensing applications. The proposed system was investigated for hydrogen sensing. Commercial Surface Acoustic Wave (SAW) resonators with resonance frequencies of 433.92 MHz and 433.42 MHz were employed in the double SAW resonator system configuration. The advantages of using this configuration include its ability for remote measurements, and insensitivity to vibrations and other external disturbances. The sensitive layer is composed of functionalized multiwalled carbon nanotubes and polyaniline nanofibers which were deposited on pre-patterned platinum metal electrodes fabricated on a piezoelectric substrate. This was mounted into the DSAWR circuit and connected in parallel. The sensor response was measured as the difference between the resonance frequencies of the SAW resonators, which is a measure of the gas concentration. The sensor showed good response towards hydrogen with a minimum detection limit of 1%.

Matched MeSH terms: Platinum

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