Choengchan, Nathawut

Loading...
Thumbnail Image
Preferred name
Choengchan, Nathawut
Alternative Name
Choengchan, N.
Choengchan, Nuthawut
Main Affiliation
Email
nathawut.ch@kmitl.ac.th

Settings

Now showing 1 - 2 of 2
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Direct determination of ethanol in alcoholic beverages based on its anti-aggregation of melamine-silver nanoparticle assembly
    (2022-12-01)
    Duangdeewong, Chomphunud
    ;
    Choengchan, Nathawut
    ;
    Wattanasin, Panwadee
    ;
    Teerasong, Saowapak
    We report a new method for determination of ethanol based on anti-aggregation of silver nanoparticles (AgNPs) in the presence of melamine. In the system, ethanol and melamine act as protecting and aggregating agents, respectively. Melamine can induce citrate-stabilized AgNPs to aggregate, leading to a color change from yellow to green. However, if the AgNPs are pre-incubated in ethanol, ethanol readily surrounds the particles by forming hydrogen bonds with the citrate stabilizer. An external nanoshell of ethanol hinders particle aggregation caused by melamine. Minor aggregation of AgNPs was observed, the solution color maintained its yellow-orange color. Higher ethanol concentrations result in a lower degree of particle aggregation. The colorimetric response of AgNPs was monitored using a UV–vis spectrophotometer at 390 nm. The current method could determine ethanol concentrations over a wide dynamic range of 5–80% (v/v), with a detection limit of 3.1% (v/v) (3SD of blank/slope). This method was applied for direct quantification of ethanol in alcoholic drinks without sample pretreatment and the results are well correlated with those of gas chromatography. Our method is convenient and cost effective, making it auspicious for ethanol monitoring in alcoholic drink manufacture and control.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Microfluidic paper-based analytical device for determination of sucrose in sugarcane juice using Benedict’s reagent
    (2022-11-01)
    Ratanawimarnwong, Nuanlaor
    ;
    Suksomphot, Vanlada
    ;
    Sornpipatpong, Khemika
    ;
    Lengwan, Supamit
    ;
    Donpudsa, Suchao
    This work presents a microfluidic paper-based analytical device (μPAD) for the determination of sucrose using the Benedict’s test. An asymmetric dumbbell-shaped hydrophobic barrier was produced by rubber stamping the barrier pattern onto a laboratory filter paper. Hydrochloric acid and solution containing sucrose were successively deposited onto the sample reservoir of the μPAD attached to a glass slide. The device was placed in a plastic bag and dipped into boiling water for accelerating the hydrolysis of sucrose into the reducing sugars. Then the Benedict’s reagent was added at the narrow straight channel connecting the two circular zones of the μPAD, which was replaced in the plastic bag and heated again for reduction of Cu(II) by the reducing sugars. Precipitate of brick-red copper(I) oxide was formed. The image of the μPAD was recorded by a smartphone. The ratio of the red to blue intensities gave linear correlation with the concentration of sucrose in the range of 0.5–10% w/v. The relative standard deviation of the measurement was less than 5% for 2 and 4% w/v sucrose (n = 10), with limit of determination, calculated using standard deviation of regression divided by slope of calibration, of 0.26% w/v sucrose. The method was successfully validated using the dinitrosalicylic acid method for sucrose measurement. Percent recoveries of sucrose were evaluated using ten sugarcane samples. The recoveries were in the range of 89 to 101%, demonstrating that there were no significant sample matrix effects on the quantification.