The Evaluation of a Lateral Flow Strip Based on the Covalently Fixed “End-On” Orientation of an Antibody for Listeria monocytogenes Detection

• Published in: Analytical chemistry (Washington) 2024-05, Vol.96 (21), p.8543-8551
• Main Authors: Thongmee, Patsara, Ngernpimai, Sawinee, Srichaiyapol, Oranee, Mongmonsin, Urairat, Teerasong, Saowapak, Charoensri, Nicha, Wongwattanakul, Molin, Lulitanond, Aroonlug, Kuwatjanakul, Waewta, Wonglakorn, Lumyai, Kendal, Rinjong Promsorn, Chompoosor, Apiwat, Daduang, Jureerut, Tippayawat, Patcharaporn
• Format: Article
• Language: English
• Subjects: analytical chemistry; Animals; Antibodies; Antibodies, Bacterial - chemistry; Antibodies, Bacterial - immunology; Antibodies, Immobilized - chemistry; Antibodies, Immobilized - immunology; Antibodies, Monoclonal - chemistry; Antibodies, Monoclonal - immunology; blood; chemical bonding; cross reaction; Cross-reactivity; detection limit; Ethylene glycol; Food; Food contamination; Food contamination & poisoning; Food Microbiology; Gold; Gold - chemistry; Humans; Limit of Detection; Listeria; Listeria monocytogenes; Listeria monocytogenes - immunology; Listeria monocytogenes - isolation & purification; Listeriosis - diagnosis; Listeriosis - microbiology; Metal Nanoparticles - chemistry; milk; Milk - chemistry; Milk - microbiology; Monoclonal antibodies; mushrooms; nanogold; Nanoparticles; Orientation behavior; Performance evaluation; point-of-care systems; quantitative analysis; Strip
• ISSN: 0003-2700; 1520-6882; 1520-6882
• DOI: 10.1021/acs.analchem.4c00533

In this study, the covalently fixed “end-on” orientation of a monoclonal Listeria monocytogenes antibody (mAb-Lis) to amino terminated oligo (ethylene glycol)-capped gold nanoparticles (NH2-TEG-AuNPs) was used to fabricate an in-house lateral flow strip (LFS), namely, the fixed “end-on” Lis-mAb-NH-TEG-AuNPs LFS. The aim was to evaluate the performance of the fixed “end-on” Lis-mAb-NH-TEG-AuNPs LFS in detecting L. monocytogenes. The proposed LFS enabled the sensitive detection of L. monocytogenes in 15 min with a visual limit of detection of 102 CFU/mL. Quantitative analysis indicated an LOD at 10 CFU/mL. The fixed “end-on” Lis-mAb-NH-TEG-AuNPs LFS showed no cross-reactivity with other pathogenic bacteria and practical performance across different food matrices, including human blood, milk, and mushroom samples. Furthermore, the clinical performance of the fixed “end-on” Lis-mAb-NH-TEG-AuNPs LFS for detecting L. monocytogenes was evaluated by using 12 clinical samples validated by the hemoculture method. It demonstrated excellent concordance with the reference methods, with no false-positive or false-negative results observed. Therefore, the fixed “end-on” Lis-mAb-NH-TEG-AuNPs LFS serves as a promising candidate for a point-of-care test (POCT), enabling the rapid, precise, and highly sensitive detection of L. monocytogenes in clinical samples and contaminated food.