Antibody Immobilization in Zinc Oxide Thin Films as an Easy-Handle Strategy for Escherichia coli Detection

Abstract

The antibody immobilization compatible with low-cost materials and label-free strategies is a challenge for biosensor device fabrication. In this study, ZnO thin film deposition was carried out on corning glass substrates by ultrasonic spray pyrolysis at 200 °C. The thin films were analyzed as platforms for enteropathogenic Escherichia coli ( E. coli EPEC) antibody immobilization. The modification of thin films from the functionalization and antibody immobilization steps was visualized using Fourier transform infrared spectroscopy (FTIR) spectroscopy, and surface changes were observed by atomic force microscopy. The obtained FTIR spectra after functionalization showed a contribution of the amino group (NH 2 ) derived from silane (3-aminopropyltrimethoxysilane). The antibody immobilization showed an amide I conserved signal corresponding to the C=O stretching vibrations and the amide II signal related to the N–H scissor vibration mode. In this way, the signals observed are correlated with the presence of antibody immobilized on the film. The ZnO film morphology changes after every stage of the process and allows observing the antibody distribution on the immobilized surface. In order to validate the antibody recognition capability as well as the E. coli EPEC detection in situ , polymerase chain reaction was used.

Zinc associated nanomaterials and their intervention in emerging respiratory viruses: Journey to the field of biomedicine and biomaterials

“…Nevertheless, ZnO nanostructures are highlighted as promising biosensing candidates due to their structural, optical, and electric properties [86] , [87] , [88] . These materials could be surface engineered for the detection of the SARS-CoV-2 virus, and as mentioned earlier, evidence of this is the pending patent of Thevasahayam et al [23] .…”

“…Numerous researchers worldwide are currently working on ZnO biosensing maturing projects. In our group, different approaches have been studied recently to observe the influence of morphological properties of these nanostructures for various applications, including bio and gas sensors [87] , [88] , [92] , [93] catalysis [94] , among others. A. Galdamez et al [87] reported the orientations of the Au orchestrated ZnO nanowires (ZnO/Au NWs) on the detection sensitivity of DNA using optical and morphological studies ( Fig.…”

“…According to the previous explanations, some of the functionalization strategies based on silane group immobilization can be employed suitably to use merely nano Zn and its compounds as a prospective biosensor platform. ZnO is one of the materials used for biofunctionalization [88] ; since it is an oxide, the generation of OH – groups is favored compared to other metallic materials that sometimes require more complex treatments. Hence, in this case, silanization represents an advantage in performing functionalization strategies, resulting in more OH – groups available for binding with the biological recognition element.…”

Morphology-Tuned Electrochemical Immunosensing of a Breast Cancer Biomarker Using Hierarchical Palladium Nanostructured Interfaces

“…The successful modification of the screen-printed electrodes with Pd nanostructures supported onto CNTs demonstrated characteristic vibrations bands at 1511, 1725, and 1227 cm –1 due to the presence of the −CC, −CO, and −C–O functional groups, respectively, from the oxidized CNTs . However, characteristic amide-I stretching (1630 cm –1 ) and amide-II band (1565 cm –1 ) correspond well to the CO stretching of the peptide backbone and bending N–H modes of immobilized anti-HER2 on the Pd-nanostructured surface. , Further, the presence of the target HER2 biomarker showed an increase in the amide-II bands at 1565 cm –1 with a concomitant broadened −NH vibration peak centered at 3315 cm –1 . The observations confirmed the successful fabrication of the Pd-nanostructured immunosensor and its response toward HER2 detection…”

Self-Assembled DNA Nanoflowers Triggered by a DNA Walker for Highly Sensitive Electrochemical Detection of Staphylococcus aureus

“…27 The chemical and physical properties of DNA nanomaterials, such as small size effect and surface effect, are exactly corresponding to the miniaturization and multifunction required by biosensors. 27 Commonly used components in biosensor construction include enzymes, 28 antibodies, 29 nucleic acids, and so on. Among them, aptamer is a kind of oligonucleotide with high affinity and specificity to targets, also known as "chemical antibodies".…”