KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 8 of 8

Some of the metrics are blocked by your
consent settings
A smartphone-integrated rapid and sensitive lateral flow test strip for quantitative detection of Fusarium spp. in maize samples
(2025-05-01)
Rotamporn, Saowalak
;
Cheubong, Chehasan
;
Sansenya, Sompong
;
Jantra, Jongjit
;
Teepoo, Siriwan
In the world, maize is considered as one of the most valuable resources. Fusarium spp. are the primary soilborne plant-pathogenic fungi that can infect maize seeds and cause diseases that potentially decrease the production of crops. This study aims to develop a rapid and sensitive lateral flow test strip (LFTS) utilizing gold nanoparticles (AuNPs) for on-site detection of Fusarium spp. in maize samples. The smartphone-integrated LFTS enables the identification of Fusarium spp. within a concentration range of 0.2–1.5 nM and achieves a limit of detection (LOD) as low as 0.063 nM. The quantitative determination of the Fusarium spp. can be completed within 8 min. Maize samples were analyzed using both the LFTS and real-time polymerase chain reaction (real-time PCR). The LFTS demonstrated effective recovery in spiked samples, with values ranging from 80.1% to 101.1%. Furthermore, the real-time PCR results exhibited significant agreement with the LFTS results. Compared to the traditional real-time PCR technique, the proposed LFTS offers a sensitive, accurate, and rapid assay for the on-site detection of Fusarium spp. in maize samples.
Some of the metrics are blocked by your
consent settings
Smartphone-based imaging colorimetric assay for monitoring the quality of curcumin in turmeric powder
(2024-07-01)
Jantra, Jongjit
;
Teepoo, Siriwan
;
Thananimit, Suchera
This research developed a colorimetric assay for semi-quantitative curcumin detection. The screening test was performed using a ferric chloride to form a brownish color which was further used to evaluate the amount of curcumin in the turmeric powder samples. The quantitative assay was performed based on the color intensity of the curcumin target using a smartphone digital image colorimetry with a developed lightbox constructed with a white light-emitting diodes (LED) light source as the measurement device. Images in red, green, and blue (RGB) color were processed to obtain relevant colors from the image and the color values were used to analyze curcumin concentrations. The intensity of the ΔB was correlated to the concentration of curcumin with high sensitivity. The method showed a linear range between 0.25 and 5 mg L−1 with the LOD and LOQ of 0.12 and 0.41 mg L−1, respectively. Sample analysis was carried out in turmeric powders. Curcumin in turmeric powder samples was simply extracted using acetonitrile followed by dilution 100 times for sample preparation. The accuracy was tested by spiking 0.25, 1.00, and 4.00 mg L−1 of standard curcumin into the turmeric sample solution. The average percentage recoveries were acceptable in all samples (90–104%). The method was validated by comparing the results obtained from the proposed method and high-performance liquid chromatography (HPLC). There was no statistically significant difference between the two methods (P = 0.05). Graphical Abstract: (Figure presented.).
Some of the metrics are blocked by your
consent settings
A highly sensitive hyperbranched Au plasmonic blackbody immunochromatographic assay for detection of leucomalachite green in fish and shrimp
(2024-01-02)
Teepoo, Siriwan
;
Jantra, Jongjit
;
Panapong, Khaunnapa
;
Ajayi, David Taiwo
A novel immunochromatographic assay (ICA) based on hyperbranched Au plasmonic blackbodies (AuPBs) with a smartphone readout was fabricated for the detection of leucomalachite green (LMG) in fish and shrimp products. The ICA was carried out in a competitive immunoassay format with AuPBs as labels. The developed AuPBs-ICA allowed for the LMG detection with a low detection limit (0.15 μg L−1) within 5 min by the smartphone reader. With the label-AuPBs ICA, the color intensity response was linearly related to the concentrations of the LMG (0.2 −1.7 μg L−1). The test line signal could be clearly distinguished at a 1.7 μg L−1 LMG as a cut-off level by the naked eye, which is lower than the conventional colloidal gold nanoparticle (2 μg L−1) and star-shaped nanoparticles (1.9 μg L−1) labeling. LMG contamination in samples was determined with the proposed AuPBs-ICA and the enzyme-linked immunosorbent (ELISA). The AuPBs-ICA results showed good agreement with those from the ELISA. The proposed AuPBs-ICA has the potential to be used as a rapid, sensitive, and simple device for the analysis of LMG residues in fish and shrimp samples.
Some of the metrics are blocked by your
consent settings
Rapid colorimetric assay based on the oxidation of 2,2-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid-diammonium salt for nitrite detection in meat products
(2024-01-01)
Jantra, Jongjit
;
Arsawiset, Supattra
;
Teepoo, Siriwan
;
Keeratirawee, Kanchalar
This work developed a rapid colorimetric method for nitrite detection in meat products. The detection was based on the reaction of nitrite with 60 mM HCl to produce radicals which further oxidized ABTS (50 µM) to form a water-soluble blue-green product (ABTS•+). The absorbance was measured at a maximum absorption wavelength of 412.5 nm. Parameters such as concentration of HCl, concentration of ABTS and reaction time were evaluated. The absorbance was linearly proportional to the concentration of nitrite (0.1–20 µM) with the limit of detection of 0.34 µM. The proposed method was a time-saving assay since it required only 2 min to complete one measurement. There was no effect of the interference produced by other ions. The assay was robust with 2.5%RSD (n = 50). In meat product samples, high accuracy was observed with the recoveries between 100 ± 2.2% and 105 ± 3.7%. The amount of nitrite in meat products detected by the ABTS method was found in the range of 5.41 − 7.62 mg/kg. The conventional Griess method was applied to determine nitrite in the same meat products. There was no statistically significant difference between the two methods (P = 0.05).
Some of the metrics are blocked by your
consent settings
Silica nanoparticle–modified paper strip–based new rhodamine B chemosensor for highly selective detection of copper ions in drinking water
(2023-08-01)
Sannok, Tadcha
;
Wechakorn, Kanokorn
;
Jantra, Jongjit
;
Kaewchoay, Netnapit
;
Teepoo, Siriwan
A new rhodamine B derivative (RDB) was synthesized and utilized for the colorimetric detection of copper ions (Cu2+). This chemosensor utilized a paper strip as a support and a smartphone as a detector for on-site quantitative detection of Cu2+ in water samples. Silica nanoparticles (SiNPs) were investigated as the modifier nanoparticles to achieve uniform color on the paper strip and showed a color response 1.9-fold higher than the one without SiNPs. The RDB chemosensor-based paper strip provided high selectivity toward Cu2+ with a detection limit of 0.7 mg/L, and the working concentrations for Cu2+ ranged from 1 to 17 mg/L. Parallel analyses of eight drinking water samples were conducted by inductively coupled plasma optical emission spectroscopy. The results were in good agreement, indicating the practical reliability of the established method with a short assay time and high selectivity. These indicate its great potential for on-site detection of Cu2+. Graphical abstract: [Figure not available: see fulltext.]
Some of the metrics are blocked by your
consent settings
Colorimetric test strip cassette readout with a smartphone for on-site and rapid screening test of carbamate pesticides in vegetables
(2022-10-01)
Rakkhun, Waraporn
;
Jantra, Jongjit
;
Cheubong, Chehasan
;
Teepoo, Siriwan
A test strip cassette integrated with a smartphone detector was developed for the colorimetric detection of carbamate pesticides in vegetables. The influence of various experimental conditions was examined for the detection of the optimum analytical performance of the test strip cassette. The test strip cassette detection of carbamate pesticides was carried out by using 140 mM of acetylthiocholine, 13 mM of 5,5′-dithiobis (2-nitrobenzoic acid), temperature at 37 °C and pH of 8.0. The developed test strip cassette platform is rapid within 5 min. Based on the inhibition effect of carbaryl on acetylcholinesterase activity, the inhibition effect of carbaryl was proportional to its concentration ranging from 1 to 50 mg/L with the detection limit of 0.30 mg/L. The limit of quantitative value was determined to be 1.0 mg/L. The spiking carbaryl, the recoveries were within 96–103% and the relative standard deviations were less than 1.56%. The analysis of carbamate pesticides residual in vegetable samples gave the results in good agreement with the most widely used commercial test kit and UPLC-MS/MS method. The developed test strip cassette required only 5 min for an assay. With the simple procedures and tiny size, it showed a great promising for the developed test strip to work on-site for carbamate pesticides detection in vegetables.
Some of the metrics are blocked by your
consent settings
On-site microfluidic paper- based titration device for rapid semi-quantitative vitamin C content in beverages
(2021-05-01)
Kaewchuay, Netnapit
;
Jantra, Jongjit
;
Khettalat, Chanyaphon
;
Ketnok, Supansa
;
Peungpra, Naruemon
A rapid, simple and on-site redox titration of vitamin C was accomplished using a novel microfluidic paper-based analytical device. The analysis was based on the combination of traditional redox titration and a microfluidic paper-based titration. The device was designed to have one sample zone connected to a titrant zone where ten different concentrations of iodine (titrant) were filled in each well. The top part of the device was a detection zone where the starch solution (indicator) was added. Vitamin C was added into a sample zone and then flowed to the titrant zone where the vitamin C was oxidized by the iodine. The excess iodine reacted with the starch indicator and endpoint of titration was reached when the blue-black product was observed by the naked eye in the detection zone. The proposed method for vitamin C detection showed the working range between 2.5 and 1,000 mg/L. The limit of detection was 2.5 mg/L. Time for an assay was only 3 sec. The developed paper-based device was applied to detect vitamin C in the real sample of beverage and the results corresponded to those obtained from traditional redox titration. The developed assay proved to be less reagent consumption compared to the traditional one. It is a truly portable device with no glassware and skilled personnel to require.
Some of the metrics are blocked by your
consent settings
Development of an automated flow-based spectrophotometric immunoassay for continuous detection of zearalenone
(2020-05-01)
Jantra, Jongjit
;
Zór, Kinga
;
Sanders, Melanie
;
De Saeger, Sarah
;
Hedström, Martin
Considering the widespread contaminations of food products with mycotoxins, it is important to develop, robust, time- and cost-effective detection methods. We developed and optimized an immunoassay using a continuous flow system for the detection of zearalenone (ZEN). The assay was performed in a flow mode using an automated sequential injection system. Time for an assay cycle was 18 Min. Under optimal conditions, the limit for quantification for ZEN was 0.40 µg L−1 with a linear dependency between concentration and signal amplitude between 0.10 and 10 µg L−1. The assay proved to be robust and reliable with 13% relative standard deviation between measurements. By dissociating the antigen–antibody complex using a regeneration solution, we showed 50 times reusability of the immobilized antibodies without affecting the antigen-binding properties.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results