Thailand Institute of Nuclear Technology
Limchoowong N.,Materials Chemistry Research Center |
Sricharoen P.,Materials Chemistry Research Center |
Techawongstien S.,Khon Kaen University |
Kongsric S.,Materials Chemistry Research Center |
Chanthai S.,Thailand Institute of Nuclear Technology
Journal of the Brazilian Chemical Society | Year: 2017
In this study, we report a new method for iodine extraction from table salts, vegetables, and other food products using ultrasound-Assisted extraction, prior to the iodine determination by inductively coupled plasma optical emission spectrometry. For the ultrasound-Assisted extraction, deionized water as the extraction solvent and an extraction time of 5 min were found to be the most optimum condition. A linear calibration curve was plotted for 0.1 to 200.0 mg L-1 iodine convention. The limits of detection and quantification were 0.049 and 0.164 mg L-1, respectively. The precision for intra-And inter-day analyses was 2.75 and 4.54%, respectively. The accuracy of the method was confirmed with certified reference materials. Recoveries in 47 real samples were ranged between 80.48 and 118.1%. Therefore, the proposed method could be considered as a rapid, simple, and environmental-friendly method (the green extraction) to determine the trace amounts of iodine in different kinds of food products. © 2017 Sociedade Brasileira de Química.
Asasutjarit R.,Thammasat University |
Theerachayanan T.,Rangsit University |
Kewsuwan P.,Thailand Institute of Nuclear Technology |
Veeranodha S.,National Science and Technology Development Agency |
And 2 more authors.
AAPS PharmSciTech | Year: 2015
The ophthalmic preparation of diclofenac sodium (DC) for relieving ocular inflammation is presently available in the market only as an eye drop solution. Due to its low occular bioavailability, it requires frequent application leading to low patients’ compliance and quality of life. This study was conducted to develop formulations of DC loaded-N-trimethyl chitosan nanoparticles (DC-TMCNs) for ophthalmic use to improve ocular biavailabiltiy of DC. DC-TMCNs varied in formulation compositions were prepared using ionic gelation technique and evaluated for their physicochemical properties, drug release, eye irritation potential, and ophthalmic absorption of diclofenac sodium. N-Trimethyl chitosan (TMC) with a 49.8% degree of quaternization was synthesized and used for DC-TMCNs production. The obtained DC-TMCNs had particle size in a range of 130–190 nm with zeta potential values of +4 to +9 mV and drug entrapment efficiencies of more than 70% depending on the content of TMC and sodium tripolyphosphate (TPP). The optimized DC-TMCNs formulation contained TMC, DC, and TPP at a weight ratio of TMC/DC/TPP = 3:1:1. Their lyophilized product reconstituted with phosphate buffer solution pH 5.5 possessed a drug release pattern that fitted within the zero-order model. The eye irritation tests showed that DC-TMCNs were safe for ophthalmic use. The in vivo ophthalmic drug absorption study performed on rabbits indicated that DC-TMCNs could improve ophthalmic bioavailability of DC. Results of this study suggested that DC-TMCNs had potential for use as an alternative to conventional DC eye drops for ophthalmic inflammation treatment. © 2015, American Association of Pharmaceutical Scientists.
Srinuttrakul W.,Thailand Institute of Nuclear Technology |
Yoshida S.,National Institutes for Quantum and Radiological science and Technology
Journal of Physics: Conference Series | Year: 2017
For long-term radiation dose assessment models, food ingestion is one of the major exposure pathways to human. In general, the stable isotopes can serve as analogues of radioisotopes. In this study, rice samples were collected from 30 paddy fields in Si Sa Ket, Yasothon and Roi Et in the northeast of Thailand in November 2014. The concentrations of stable cesium (Cs-133) and strontium (Sr-88) in polished rice were determined by inductively coupled plasma mass spectrometry (ICP-MS). The standard reference material of rice flour (NIST 1568a) with spiked Cs and Sr was used to validate the analytical method. The concentration of Cs in polished rice from Si Sa Ket, Yasothon and Roi Et was 0.158 ± 0.167 mg kg-1, 0.090 ± 0.117 mg kg-1 and 0.054 ± 0.031 mg kg-1, respectively. The concentration of Sr in polished rice from Si Sa Ket, Yasothon and Roi Et was 0.351 ± 0.108 mg kg-1, 0.364 ± 0.215 mg kg-1 and 0.287 ± 0.102 mg kg-1, respectively. Comparison of the results with Japanese data before the Fukushima Di-ichi nuclear power plant accident showed that the concentrations of both Cs and Sr for Thai rice were higher than those for Japanese rice. © Published under licence by IOP Publishing Ltd.
Nikjoo H.,Karolinska Institutet |
Emfietzoglou D.,University of Ioannina |
Liamsuwan T.,Thailand Institute of Nuclear Technology |
Taleei R.,Southwestern Medical Center |
And 2 more authors.
Reports on Progress in Physics | Year: 2016
The purpose of this paper has been to review the current status and progress of the field of radiation biophysics, and draw attention to the fact that physics, in general, and radiation physics in particular, with the aid of mathematical modeling, can help elucidate biological mechanisms and cancer therapies. We hypothesize that concepts of condensed-matter physics along with the new genomic knowledge and technologies and mechanistic mathematical modeling in conjunction with advances in experimental DNA (Deoxyrinonucleic acid molecule) repair and cell signaling have now provided us with unprecedented opportunities in radiation biophysics to address problems in targeted cancer therapy, and genetic risk estimation in humans. Obviously, one is not dealing with 'low-hanging fruit', but it will be a major scientific achievement if it becomes possible to state, in another decade or so, that we can link mechanistically the stages between the initial radiation-induced DNA damage; in particular, at doses of radiation less than 2 Gy and with structural changes in genomic DNA as a precursor to cell inactivation and/or mutations leading to genetic diseases. The paper presents recent development in the physics of radiation track structure contained in the computer code system KURBUC, in particular for low-energy electrons in the condensed phase of water for which we provide a comprehensive discussion of the dielectric response function approach. The state-of-the-art in the simulation of proton and carbon ion tracks in the Bragg peak region is also presented. The paper presents a critical discussion of the models used for elastic scattering, and the validity of the trajectory approach in low-electron transport. Brief discussions of mechanistic and quantitative aspects of microdosimetry, DNA damage and DNA repair are also included as developed by the authors' work. © 2016 IOP Publishing Ltd.
Tiyapun K.,Thailand Institute of Nuclear Technology |
Wetchagarun S.,Thailand Institute of Nuclear Technology
Journal of Physics: Conference Series | Year: 2017
The neutronic analysis of TRIGA Mark II reactor has been performed. A detailed model of the reactor core was conducted including standard fuel elements, fuel follower control rods, and irradiation devices. As the approach to safety nuclear design are based on determining the criticality (keff), reactivity worth, reactivity excess, hot rod power factor and power peaking of the reactor, the MCNPX code had been used to calculate the nuclear parameters for different core configuration designs. The thermal-hydraulic model has been developed using COOLOD-N2 for steady state, using the nuclear parameters and power distribution results from MCNPX calculation. The objective of the thermal-hydraulic model is to determine the thermal safety margin and to ensure that the fuel integrity is maintained during steady state as well as during abnormal condition at full power. The hot channel fuel centerline temperature, fuel surface temperature, cladding surface temperature, the departure from nucleate boiling (DNB) and DNB ratio were determined. The good agreement between experimental data and simulation concerning reactor criticality proves the reliability of the methodology of analysis from neutronic and thermal hydraulic perspective. © Published under licence by IOP Publishing Ltd.
Rattanaphra D.,Thailand Institute of Nuclear Technology |
Rattanaphra D.,Kasetsart University |
Harvey A.P.,Northumbria University |
Thanapimmetha A.,Kasetsart University |
Srinophakun P.,Kasetsart University
Fuel | Year: 2012
Simultaneous catalysed transesterification of rapeseed oil and esterification of 10 wt% myristic acid with methanol was studied using sulphated zirconia and in the absence of catalyst. The maximum total FAME content of 86% was obtained at a catalyst loading of 3 wt%, temperature of 170°C, pressure of 22 bars, molar ratio of oil to methanol of 1:20 and stirring rate of 600 rpm for 60 min. At these conditions, FFA was observed to reach 2.95% (2.94 mg/ml sol.). Thermo/catalytic cracking and hydrolysis of triglyceride was presumed to form the FFA. Water was also formed: dehydration of methanol is likely to be the principal source. Three sets of main reactions occurred at distinctly different rates. Esterification of myristic acid was the most rapid reaction. Direct transesterification of triglyceride and side-reactions of thermo/catalytic cracking of triglyceride followed by esterification of fatty acid and hydrolysis of triglyceride followed by esterification of fatty acid occurred afterward. Dehydration of methanol was observed throughout the reaction, producing a constant supply of water, thereby facilitating hydrolysis reactions. © 2012 Elsevier Ltd. All rights reserved.
Silva K.,Thailand Institute of Nuclear Technology |
Ishiwatari Y.,University of Tokyo |
Takahara S.,Japan Atomic Energy Agency
Reliability Engineering and System Safety | Year: 2014
The Fukushima Accident emphasizes the need to integrate the assessments of health effects, economic impacts, social impacts and environmental impacts, in order to perform a comprehensive consequence assessment of severe accidents in nuclear power plants. "Cost per severe accident" is introduced as an index for that purpose. The calculation methodology, including the consequence analysis using level 3 probabilistic risk assessment code OSCAAR and the calculation method of the cost per severe accident, is proposed. This methodology was applied to a virtual 1,100 MWe boiling water reactor. The breakdown of the cost per severe accident was provided. The radiation effect cost, the relocation cost and the decontamination cost were the three largest components. Sensitivity analyses were carried out, and parameters sensitive to cost per severe accident were specified. The cost per severe accident was compared with the amount of source terms, to demonstrate the performance of the cost per severe accident as an index to evaluate severe accident consequences. The ways to use the cost per severe accident for optimization of radiation protection countermeasures and for estimation of the effects of accident management strategies are discussed as its applications. © 2013 Elsevier Ltd. All rights reserved.
Chittasupho C.,Srinakharinwirot University |
Lirdprapamongkol K.,Chulabhorn Research Institute |
Kewsuwan P.,Thailand Institute of Nuclear Technology |
Sarisuta N.,Thammasat University
European Journal of Pharmaceutics and Biopharmaceutics | Year: 2014
Doxorubicin is used to treat a variety of cancers, but dose limiting toxicity or intrinsic and acquired resistance limits its application in many types of cancer. CXCR4 is a chemokine receptor which implicates in metastasis of cancers including lung cancer. LFC131, a peptide inhibitor of CXCR4-ligand binding, is a linear type of low molecular weight CXCR4 antagonist. In this study, we investigated the possibility of using LFC131 conjugated nanoparticles for targeted delivering doxorubicin to CXCR4 expressing lung cancer cells. The LFC131 peptide was conjugated to sodium carboxylmethyl cellulose coated poly(dl-lactic-co-glycolic acid) (PLGA) nanoparticles. Binding and cellular uptake of doxorubicin-loaded LFC131 conjugated nanoparticles (LFC131-DOX NP) in adenocarcinomic human alveolar basal epithelial cells called A549 cells were higher and faster than that of untargeted nanoparticles. The specificity of CXCR4-mediated internalization of LFC131-DOX NPs was confirmed by using free LFC131 peptide or anti-CXCR4 monoclonal antibody. Cell studies suggested that sustained release of doxorubicin afforded by PLGA nanoparticles may enable LFC131-DOX NP as a targeted and controlled release drug delivery system. © 2014 Elsevier B.V. All rights reserved.
Wetchagarun S.,University of Washington |
Wetchagarun S.,Thailand Institute of Nuclear Technology |
Riley J.J.,University of Washington
Physics of Fluids | Year: 2010
The dispersion and temperature distribution of inertial particles are important in many turbulent, multiphase flow problems. In order to understand these better, direct numerical simulations (DNSs) are performed for inertial particles in a fluid with a constant temperature gradient and whose motion is either statistically stationary or decaying, isotropic turbulence. It is found that, for long times, the dispersion of inertial particles is the greatest when the Stokes number, Stη=τp/τη, is of order 1, where τp and τη are, respectively, the particle response time and the flow Kolmogorov time scale. A similar result is found for the long time behavior of the time rate of change of the mean-square particle temperature fluctuations, d
Hemvichian K.,Thailand Institute of Nuclear Technology |
Chanthawong A.,Thailand Institute of Nuclear Technology |
Suwanmala P.,Thailand Institute of Nuclear Technology
Radiation Physics and Chemistry | Year: 2014
Superabsorbent polymer (SAP) was synthesized by radiation-induced grafting of acrylamide (AM) onto carboxymethyl cellulose (CMC) in the presence of a crosslinking agent, N,N'-methylenebisacrylamide (MBA). The effects of various parameters, such as dose, the amount of CMC, AM, MBA and ionic strength on the swelling ratio were investigated. In order to evaluate its controlled release potential, SAP was loaded with potassium nitrate (KNO3) as an agrochemical model and its potential for controlled release of KNO3 was studied. The amount of released KNO3 was analyzed by an inductively coupled plasma mass spectrometry (ICP-MS). The results from controlled release experiment agreed very well with the results from swelling experiment. The synthesized SAP was characterized by Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The obtained SAP exhibited a swelling ratio of 190g/g of dry gel. © 2014.