Integration of a hamper pad on test strips for improved sensitivity of carbendazim detection

• Published in: Talanta (Oxford) 2024-06, Vol.273, p.125911-125911, Article 125911
• Main Authors: Makkala, Pumnatthiga, Ruantip, Sirowan, Buakeaw, Anumart, Chaiyo, Sudkate, Khongchareonporn, Nanthika
• Format: Article
• Language: English
• Subjects: antibodies; brown rice; Carbendazim; detection limit; glutinous rice; Hamper pad; high performance liquid chromatography; Lateral flow immunoassay; paddies; polyvinyl alcohol; Polyvinyl alcohol polymer; Sensitivity improvement; soybeans; technology
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2024.125911

Lateral flow immunoassays (LFIAs) are widely used to determine carbendazim (CBZ) residues in food products due to their advantages of low cost, ease and rapid use, on-site detection capability. However, conventional LFIAs have low detection sensitivity. Although improvements have been made to increase the sensitivity, it is not sufficient. Here, a hamper pad, polyvinyl alcohol coated on a nitrocellulose membrane, was integrated to enhance the sensitivity of LFIA for CBZ detection. The hamper pad was inserted between the conjugated and nitrocellulose pads to delay the flow rate, thereby increasing the possibility of the antibody and target analyte binding. This platform exhibited a fourfold sensitivity increase in CBZ detection compared with the conventional LFIA, and its limit of detection was 1.6 ng/mL. In addition, a single-step operation was successfully applied to detect CBZ in rice (white rice, brown rice, sticky rice, and paddy) and soybean samples, with acceptable recoveries of 93.6%–120.0%. This novel device was compared to the standard high-performance liquid chromatography method, which shows high accuracy with a Kappa coefficient of 0.91. Therefore, improved sensitivity with a rapid, simple, and inexpensive device could facilitate the detection of CBZ residues in agricultural products for on-field screening and improved user-friendliness. [Display omitted] •A polymer-coated hamper pad was used to improve the detection sensitivity of LFIA.•The hLFIA provides a 4-fold increase in cutoff value for carbendazim detection.•Ease of scale-up production of high-sensitivity hLFIA is reported.•A test strip has been used to successfully evaluate carbendazim in food samples.