Phromyothin, Darinee

Preferred name

Alternative Name

Phromyothin, D.

Phromyothin, Darinee Sae Tang

Main Affiliation

Integrated Innovative Technology

darinee.ph@kmitl.ac.th

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Electrochemical analysis of cypermethrin using a gold printed circuit board electrode modified with poly(methyl methacrylate)
(2019-01-01)
Leepheng, Piyawan
;
Phromyothin, Darinee
A gold printed circuit board (PCB) electrode modified with poly(methyl methacrylate) (PMMA) was studied for cypermethrin pesticide detection. The morphology surface of the fabricated electrode was characterized by atomic force microscopy. The electrochemical study was characterized by cyclic voltammetry and impedance spectroscopy using a fabricated electrode as a working electrode, platinum sheet as a counter electrode and silver/silver chloride as a reference electrode. The fabricated electrode has suitable detection for cypermethrin with good selectivity, high sensitivity at 0.279 μA ppm<sup>-1</sup>, low limit of detection at 0.34 ppm, high accuracy, is inexpensive and can be applied to the portable electrochemical sensor device for detection of cypermethrin in real samples.
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A study and characterization of photophysical properties of fluorene derivative thin flim
(2016-01-01)
Sirijarutus, Wattanaruk
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Charoensuwan, Sittan
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Thanakit, Prawonwan
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Pratontep, Sirapat
;
Phromyothin, Darinee Sae Tang
An emissive layer, fluorene derivative, was performed for organic light-emitting device properties. The preparation of fluorene derivative thin film by spin coating and convective technique was studied the band diagram of thin films which its properties out as the energy gap (Eg). UV-Visible spectrophotometer has been used to investigate the thin film properties. The results indicate spectacular property which occurs in the optical properties, fluorescence in thin film and luminescence as a green light in device that it could be applied as emissive layer for organic light-emitting diodes (OLEDs) due to the appropriate work function with cathode and anode, aluminum metal and indium tin oxide layer (ITO), respectively.
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Quantum chemical study of Thiadiazole molecular sensors for detection of heavy metal, A DFT calculation
(2017-01-01)
Chattrairat, K.
;
Phromyothin, D.
Using density functional theory (DFT), the binding energies, band spectra, optical properties and electron distribution of thiadiazole derivatives were investigated to detect the metals. The results indicate that the molecular sensors M1 and M3 can detect Pb<sup>2+</sup> with the lowest binding energy. The electron density distributions show a transfer of electron from the aromatic group of the molecular sensor fluorophore to the metal ion when a photon is absorbed.
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Surface modification: PEG / Dextran encapsulation of SPIONs
(2017-01-01)
Pansailom, Nichakorn
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Rattanamai, Songsak
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Leepheng, Piyawan
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Rattanawarinchai, Prapakorn
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Chattrairat, Kunanon
In this work, we present an encapsulation of superparamagnetic iron oxide nanoparticles (SPIONs) by dextran40 and polyethylene glycol. The SPIONs were used due to their responsibility to the external magnetic field that recovered easily. Considering the biocompatibility, the SPIONs were encapsulated by dextran40 and polyethylene glycol MW 400 with the suitable combination ratio. The efficiency of encapsulation was evaluated and confirmed using FTIR, and TGA, respectively. The further propose of SPIONs coated with dextran40 and PEG400 can be applied in medical therapy and drug delivery.
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Effect of amino-, mercapto-silane coupling as a molecular bridge of polyvinyl chloride ion-selective membrane on silicon nitride for nitrate ISFET sensors
(2020-06-01)
Chaisriratanakul, Woraphan
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Bunjongpru, Win
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Pankiew, Apirak
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Srisuwan, Awirut
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Jeamsaksiri, Wutthinan
This paper presents a modification of a Si<inf>3</inf>N<inf>4</inf> Polyvinyl chloride (PVC) membrane on a surface of an ion selective field effect transistor (ISFET) using silane with two different functional groups for comparison of nitrate sensing characteristics. Effects of amino (NH<inf>2</inf>) and thiol groups (SH) toward structures and characteristics of nitrate sensors were analyzed using the following techniques: ellipsometry, scanning electron microscope (SEM), infrared spectroscopy (FTIR), zeta potential and electrochemical impedance spectroscopy (EIS). After surface modification, the thickness of the silane layers for both cases were similar with uniform surface topology. Absolute zeta potentials of PVC ion-selective membrane (7.65 mV) and Si<inf>3</inf>N<inf>4</inf> surface modification with MPTMS (-51.46 mV) reflected the surface functional group and showed that membranes could be bonded to the PVC ion-selective membrane. Since APTMS produced higher EIS than MPTMS, the resulting nitrate sensors modified by MPTMS had higher sensitivity than the sensors with APTMS. Finally, the modified sensors had a useful life time of 3 months.
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Fabrication of zinc oxide nanorods for photoelectrochemical water splitting application
(2016-01-01)
Phetban, Poosuda
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Khemasiri, Narathon
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Kalasung, Sukol
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Jessadaluk, Sukukittaya
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Horprathum, Mati
Zinc oxide nanorods (ZnO-NRs) as a photoelectrochemical water splitting electrode have been fabricated by the seed-assisted hydrothermal process. Initially, ZnO-seed thin film was deposited on indium doped tin oxide (ITO) via DC magnetron sputtering system. Period to fabricate ZnO-NRs, the precursor concentration of zinc nitrate (Zn(NO<inf>3</inf>)<inf>2</inf>) and hexamethylenetetramine (HMTA) were precisely controlled during 10-50 mM, meanwhile the ratio was constantly kept at 1:1. The crystallography and surface morphology of the fabricated ZnO-NRs were investigated by X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM). The XRD patterns perform wurtzite ZnO crystal structure of with the prefered orientation in (002) and (101) plane. According to FE-SEM photograph, growth rate, density and diameter of the fabricated ZnO-NRs electrode significantly increase, with the increasing of the precursor concentration. This precursor concentration provides a crucial role on the feature of ZnO-NRs for photoelectrochemical water splitting electrode. Finally, the photoelectrochemical water splitting performance was examined and provided that the precursor concentration became close to 30 mM in 1 M Na<inf>2</inf>SO<inf>4</inf> exhibited the highest photocurrent.
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Enhancement of Electrochemical Detection of Gluten with Surface Modification Based on Molecularly Imprinted Polymers Combined with Superparamagnetic Iron Oxide Nanoparticles
(2022-01-01)
Limthin, Dalawan
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Leepheng, Piyawan
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Klamchuen, Annop
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Phromyothin, Darinee
Novel molecularly imprinted polymers (MIPs) represent a selectively recognized technique for electrochemical detection design. This rapid and simple method prepared via chemical synthesis consists of a monomer crosslinked with an initiator, whereas low sensitivity remains a drawback. Nanomaterials can improve charge transfer for MIP surface modification in order to overcome this problem. SPIONs have semiconductor and superparamagnetic properties that can enhance carrier mobility, causing high sensitivity of electrochemical detection. In this work, surface modification was achieved with a combination of MIP and SPIONs for gluten detection. The SPIONs were synthesized via the chemical co-precipitation method and mixed with MIPs by polymerizing gluten and methyl methacrylate (MMA), presented as a template and a monomer. Magnetic MIP (MMIP) was modified on a carbon-plate electrode. The morphology of modified electrode surfaces was determined by scanning electron microscopy–energy-dispersive X-ray spectrometry. The performance of the MMIP electrode was confirmed by cyclic voltammetry, amperometry, and electrochemical impedance spectroscopy. The MMIP electrode for gluten detection shows a dynamic linear range of 5–50 ppm, with a correlation coefficient of 0.994 and a low detection limit of 1.50 ppm, which is less than the U.S. Food and Drug Administration requirements (20 ppm); moreover, it exhibits excellent selectivity, sensitivity, stability, and reproducibility.
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Efficiency of SPIONs functionalized with polyethylene glycol bis(amine) for heavy metal removal
(2016-09-15)
Wanna, Yongyuth
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Chindaduang, Anon
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Tumcharern, Gamolwan
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Phromyothin, Darinee
;
Porntheerapat, Supanit
Hybrid magnetic nanoparticles based on poly(methylmethacrylate) (PMMA) and super-paramagnetic iron oxide nanopaticles (SPIONs) with selective surface modification has been developed for heavy metal removal by applying external magnetic fields. The nanoparticles were prepared by the emulsion polymerization technique in an aqueous suspension of SPIONs. The hydrolysis of carboxyl functional group was then applied for grafting polyethylene glycol bis(amine)(PEG-bis(amine)) onto the PMMA-coated SPIONs. The morphology, the chemical structure and the magnetic properties of the grafted nanoparticles were investigated. The efficiency of the hybrid nanoparticles for heavy metal removal were conducted on Pb(II), Hg(II), Cu(II) and Co(II) in aqueous solutions.The metal concentration in the solutions after separation by the hybrid nanoparticles was determined by inductively coupled plasma optical emission spectrometer (ICP-OES). The results show the heavy metal uptake ratios of 0.08, 0.04, 0.03, and 0.01 mM per gramme of the grafted SPIONs for Pb(II), Hg(II), Cu(II), and Co(II), respectively. A competitive removal of Cu(II), Pb(II), Co(II) and Hg(II) ions in mixed metal salt solutions has also been studied.The heavy metal removal efficiency of the hybrid nanoparitcles was found to depend on the cation radius, in accordance with capture of metal ions by the amine group.
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High performance metal surface coating using Ta2O5 thin film prepared by D. C. magnetron sputtering
(2014-01-01)
Khemasiri, Narathon
;
Chananonnawathorn, Chanunthorn
;
Horprathum, Mati
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Eiamchai, Pitak
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Chindaudom, Pongpan
Tantalum oxide (Ta<inf>2</inf>O<inf>5</inf>) thin films were deposited as the protective layers for the metal surface finishing by the DC reactive magnetron sputtering system. The effect of the Ta<inf>2</inf>O<inf>5</inf> film thickness, ranging from 25 nm to 200 nm, on the physical properties and the anti-corrosive performance were investigated. The grazing-incidence X-ray diffraction (GIXRD) and the atomic force microscopy (AFM) were used to examine the crystal structures and the surface topologies of the prepared films, respectively. The XRD results showed that the Ta<inf>2</inf>O<inf>5</inf> thin films were all amorphous. The AFM micrographs demonstrated the film morphology with quite smooth surface features. The surface roughness tended to be rough when the film thickness was increased. To examine the protective performance of the films, the poteniostat and galvanometer was utilized to examine the electrochemical activities with the 1M NaCl as the corrosive electrolyte. The results from the I-V polarization curves (Tafel slope) indicated that, with the Ta<inf>2</inf>O<inf>5</inf> thin film, the current density was significantly reduced by 3 orders of magnitude when compared with the blank sample. Such results were observed because of fully encapsulated surface of the samples were covered with the sputtered Ta<inf>2</inf>O<inf>5</inf> thin films. The study also showed that the Ta<inf>2</inf>O<inf>5</inf> thin film deposited at 50 nm yielded the most extreme protective performance. The Ta<inf>2</inf>O<inf>5</inf> thin films therefore could be optimized for the smallest film thickness for highly potential role in the protective performance of the metal surface finishing products. © (2014) Trans Tech Publications, Switzerland.
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Development and characterization of nano-cream preparation containing natural extract using nanoemulsion techniques
(2017-01-01)
Charoenkul, Kalyakorn
;
Phromyothin, Darinee
The objective of this study is to investigate the formulation, preparation and characterization of nano-cream from squalene in olive oil, virgin coconut oil and turmeric using nanoemulsion techniques. The 'shock method' via a phase inversion temperature (PIT) was prepared the nanoemulsion which was kinetically stable system, comprised of oil droplets dispersed in aqueous media using tween 80 and span 80 as emulsifier and stabilized by nonylphenol ethoxylate as surfactant, respectively. Characterization and evaluation were generally carried out by preliminary characterization, pH, conductivity, determinations of particle size and thermal stability. The obtained nanoemulsion from squalene and virgin coconut oil with the ratio 0.5:3.6 was cloudy white color with an average particle size of 400 nm and stable without any phase separation. Nanoemulsions with the addition of turmeric were opaque yellow and particle size is found to decrease to 200 nm.

Phromyothin, Darinee

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