Antibody conjugated Au/Ir@Cu/Zn-MOF probe for bacterial lateral flow immunoassay and precise synergistic antibacterial treatment

• Published in: Biosensors & bioelectronics Vol. 224; p. 115033
• Main Authors: Zhong, Yingying, Zheng, Xin Ting, Li, Qing-lan, Loh, Xian Jun, Su, Xiaodi, Zhao, Suqing
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 15.03.2023
• Subjects: Anti-Bacterial Agents - pharmacology; Antibodies; Antibody targeting; Au/Ir@Cu/Zn-MOF nanocomposite; Bacteria; Biosensing Techniques; Chemodynamic therapy; Hydrogen Peroxide; Immunoassay; Immunoconjugates; Lateral flow sensor; Metal Nanoparticles; Photothermal therapy; Staphylococcus aureus; Staphylococcus aureus detection; Zinc; Au/Ir@Cu/Zn-MOF nanocomposite; Photothermal therapy; Antibody targeting; Chemodynamic therapy; Lateral flow sensor; Staphylococcus aureus detection
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2022.115033

Staphylococcus aureus is one of the most prevalent threats to public health. Rapid detection with high sensitivity and targeted killing is crucial to curb its spread. Herein, a metal-bearing nanocomposite, consisting of a bimetallic nanoparticle and a metal-organic framework (Au/Ir@Cu/Zn-MOF) was constructed. Upon conjugation with anti-S. aureus antibody, this nanocomposite (Ab-Au/Ir@Cu/Zn-MOF) was exploited for its dual functions, i.e. as a reporting probe in a lateral flow immunoassay and a high efficiency antibacterial reagent. Benefiting from the enrichment of Au/Ir NPs by the Cu/Zn-MOF, the Au/Ir@Cu/Zn-MOF-based lateral flow immunoassay sensor exhibited a visual limit of detection of 103 CFU/mL, which was100 times more sensitive than Au/Ir-based sensor. Moreover, the Ab-Au/Ir@Cu/Zn-MOF probe possessed synergistic photothermal-chemodynamic bactericidal effect that specifically targeted against S. aureus. Under a co-treatment by H2O2 (0.4 mM) and 808 nm near infrared irradiation (1 W/cm2, 5 min), complete sterilization of 5 × 105–106 CFU/mL S. aureus was achieved at a nanocomposite concentration as low as 6.25 μg/mL. The superior antibacterial efficiency was attributable to the three-fold properties of the Ab-Au/Ir@Cu/Zn-MOF probe: (1) enhanced multi-enzyme mimicking activities that promote reactive oxygen species generation, (2) high photothermal activity (efficiency of 53.70%), and (3) bacteria targeting ability via the antibody coating. By changing the antibody, this nanocomposite can be tailored to target a wide range of bacteria species, for detection and for precise antibacterial treatment.