Epitope-imprinted graphene quantum dot fluorosensors for rapid and selective detection of Escherichia coli O157:H7 in fresh cow's milk
Microchemical Journal, cilt.224, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 224
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.microc.2026.117656
- Dergi Adı: Microchemical Journal
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Chemical Abstracts Core, Chimica, Index Islamicus
- Anahtar Kelimeler: E. coli O157:H7, Epitope-imprinted graphene quantum dots, Fluorescence quenching
- İstanbul Medipol Üniversitesi Adresli: Evet
Özet
Accurate and efficient detection of Escherichia coli O157:H7 (E. coli O157:H7) remains a significant global public health issue. In this study, we developed a fluorescence sensor based on bacterial epitope-imprinted graphene quantum dots for targeted bacterial detection. These quantum dots were easily produced using monomers such as oligo (ethylene glycol) monomethyl ether methacrylate (OEGMA) and copper (II) acrylate, with EGDMA as a crosslinker, and templates of histidine-tagged peptides from E. coli O157:H7 (KT-12, YA-13, and TV-10). The polymer layer was applied to the surface of the quantum dots, and after removing the template, it was used to bind E. coli O157:H7 via fluorescence spectroscopy selectively. The presence of bacteria caused specific binding and fluorescence quenching. The detection process was completed in less than 10 min, with a linear response range from 101 to 108 cfu/mL and a low detection limit. The linear fluorescence quenching of the sensor ranged from 108 to 101 cfu/mL, with an R2 of 0.9997 and a detection limit of 2.75 ≈ 3 cfu/mL in 10,000-fold diluted fresh cow milk samples. Testing on real samples showed high recoveries ranging from 97.4% to 101.9%. Overall, this fluorosensor offers a rapid, sensitive, specific, and reliable method for detecting E. coli O157:H7.