{
  "abstract": "This study aimed to increase the γ-aminobutyric acid (GABA) content in rice grains and develop surface-modified silver nanoparticles (AgNPs) as a simple colorimetric chemosensor for its detection. To stimulate GABA production, rice grains from the Kor Kho 6 (RD6) and Khao Dawk Mali 105 (KDML105) cultivars were treated with various solutions targeting the GABA metabolic pathways. Results demonstrated that simultaneously supplementing the GABA substrate with 2% (w/v) monosodium glutamate and inhibiting GABA transaminase with a 2% (w/v) rosmarinic acid solution yielded the highest GABA content. For quantitative detection of GABA, surface-modified AgNPs with citrate (Cit-AgNPs) were synthesized and characterized using UV–visible spectrophotometry, transmission electron microscopy (TEM), and dynamic light scattering (DLS). The Cit-AgNPs successfully quantified GABA levels, as evidenced by a colorimetric shift from yellow to green. This transition corresponded to a decrease in absorbance at 393 nm and the emergence of a shoulder peak in the 450–550 nm region. This sensing mechanism was subsequently integrated with the PhotoMetrix smartphone application, offering a practical and accessible platform for GABA quantification. Analysis of RGB color intensity revealed a linear relationship between the green color intensity and GABA concentration in the range of 50–500 ppm (R2 = 0.9757). The assay demonstrated a limit of detection (LOD) of 44.20 ppm and a limit of quantification (LOQ) of 147.00 ppm. Furthermore, the GABA content measured in rice grains using this smartphone-based method closely aligned with the standard high-performance liquid chromatography (HPLC) results, exhibiting an error margin of approximately 5%. These findings indicate that this smartphone-based method holds significant potential for practical application in resource-limited testing facilities.",
  "abstract_shown": true,
  "affiliations": [
    "Srinakharinwirot University , , ,"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 5,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Pan Tongraung"
    },
    {
      "affs": [
        0
      ],
      "name": "Ladnaphone Hadaoheuang"
    },
    {
      "affs": [
        0
      ],
      "name": "Piyathida Piyasakulwong"
    },
    {
      "affs": [
        0
      ],
      "name": "Pichamon Phonraksa"
    },
    {
      "affs": [
        0
      ],
      "name": "Supakan Rattanakon",
      "orcid": "0009-0009-9753-2276"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2vxrmtn4j57qw.bib",
  "cited_by": 0,
  "doi": "10.1021/acsomega.6c03525",
  "fulltext_url": "https://europepmc.org/articles/PMC13688463",
  "id": "2vxrmtn4j57qw",
  "issns": [
    "2470-1343"
  ],
  "landing_url": "https://pubs.acs.org/acsodf/article/11/41/62606/5444919/A-Smartphone-Based-Silver-Nanoparticle-Assay-for",
  "language": "eng",
  "licence": "CC-BY-NC-ND-4.0",
  "licence_label": "CC BY-NC-ND 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2504|Gold and Silver Nanoparticles Synthesis and Applications"
    ]
  ],
  "openalex": "W7220657882",
  "pdf_url": "https://pubs.acs.org/doi/pdf/10.1021/acsomega.6c03525",
  "pmcid": "PMC13688463",
  "pmid": "42923339",
  "published": "2026-10-05",
  "publisher": "American Chemical Society (ACS)",
  "ris": "https://research.draconitic.com/paper/2vxrmtn4j57qw.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:39Z",
      "native_id": "10.1021/acsomega.6c03525",
      "source": "crossref",
      "url": "https://pubs.acs.org/acsodf/article/11/41/62606/5444919/A-Smartphone-Based-Silver-Nanoparticle-Assay-for"
    },
    {
      "first_seen": "2026-10-30T12:20:36Z",
      "native_id": "MED:42923339",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42923339"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:2504|Gold and Silver Nanoparticles Synthesis and Applications",
      "subfield": "materials-polymers"
    }
  ],
  "title": "A Smartphone-Based Silver Nanoparticle Assay for Detecting Enhanced Gamma-Aminobutyric Acid Content in Germinated Rice via Metabolic Modulation",
  "title_text": "A Smartphone-Based Silver Nanoparticle Assay for Detecting Enhanced Gamma-Aminobutyric Acid Content in Germinated Rice via Metabolic Modulation",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:20:36Z",
  "url": "https://research.draconitic.com/paper/2vxrmtn4j57qw",
  "venue": "ACS Omega",
  "versions": []
}