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Sugar–Lectin Interactions for Direct and Selective Detection of Escherichia coli Bacteria Using QCM Biosensor    
Yazarlar
Gaddi Eshun
Heather Crapo
Doç. Dr. İdris YAZGAN
Kastamonu Üniversitesi, Türkiye
Lauren E Cronmiller
Omowunmi Sadik
Özet
Pathogenic Escherichia coli (E. coli) remains a safety concern in the preservation and quality of green leafy vegetables. Sugar–lectin interactions provide a reliable, specific, and effective sensing platform for the detection of bacteria as compared to the tedious conventional plate counting technique. Herein, we present the synthesis of 4-(N-mannosyl) benzoic acid (4-NMBA) and 4-thiophenyl-N-mannose (4-TNM) via a two-step reductive amination for the detection of E. coli using a quartz crystal microbalance (QCM) biosensor. The 4-NMBA was synthesized with mannose and para-aminobenzoic (4-PBA), while the 4-TNM was synthesized with mannose and 4-aminophenyl disulfide (4-AHP) using water and acetic acid in a 1:1 ratio. The resultant structure of mannose derivatives (4-NMBA and 4-TNM) was characterized and confirmed using analytical tools, such as Mass Spectrometer, SEM, and FTIR. The choice of ligands (mannose derivatives) is ascribed to the specific recognition of mannose to the FimH lectin of the type 1 pilus of E. coli. Furthermore, the 4-PBA and 4-AHP conjugated to mannose increase the ligand affinity to FimH lectins. The setup of the QCM biosensor was composed of modification of the crystal surface and the covalent attachment of ligands for the detection of E. coli. The piezoelectric effect (frequency shift of the quartz) was proportional to the change in mass added to the gold crystal surface. Both the 4-NMBA- and 4-TNM-coated QCM sensors had a limit of detection of 3.7 CFU/mL and 6.6 CFU/mL with a sensitivity of 2.56 × 103 ng/mL and 8.99 × 10−5 ng/mL, respectively, within the dynamic range of 103 to 106 CFU/mL. This study demonstrates the application of ligand-coated QCM biosensors as a cost-effective, simple, and label-free technology for monitoring pathogenic bacteria via molecular interactions on crystal surfaces.
Anahtar Kelimeler
bacterial enumeration | E. coli | FimH | ligands | quartz crystal microbalance | selectivity | sensor
Makale Türü Özgün Makale
Makale Alt Türü SSCI, AHCI, SCI, SCI-Exp dergilerinde yayımlanan tam makale
Dergi Adı MDPI AG
Dergi ISSN 2079-6374
Dergi Tarandığı Indeksler SCI-Expanded
Dergi Grubu Q1
Makale Dili Türkçe
Basım Tarihi 03-2023
Cilt No 13
Doi Numarası 10.3390/bios13030337
Makale Linki http://dx.doi.org/10.3390/bios13030337