Single-Probe-Based Colorimetric and Photothermal Dual-Mode Identification of Multiple Bacteria

Abstract

Effective identification of multiple pathogenic bacteria in unknown samples is important for disease prevention and control but remains a challenge yet. A single-mode arraybased sensing approach is simple and sensitive, but it usually relies on the use of multiple crossreactive receptors to construct sensor arrays, which is cumbersome and insufficiently accurate. Here, we developed a sensor array with colorimetric and photothermal dual mode of differentiating multiple pathogenic bacteria. The sensor array was based on boronic acidfunctionalized Au−Fe 3 O 4 nanoparticles (BA−GMNPs), which not only possess localized surface plasmon resonance properties, showing a burgundy color similar to that of AuNPs, but also exhibit mild superparamagnetism, allowing for the differentiation of bacteria before and after binding to the nanoparticles. Immobilization of BA−GMNPs on the bacterial cell surface by covalent bonding would diminish NaCl-induced assembly of BA−GMNPs. Different BA− GMNPs@bacterial complexes differed in their ability to resist assembly and produced different colorimetric and photothermal response signals. A unique molecular fingerprint of each bacterium was obtained by linear discriminant analysis of the response patterns, demonstrating an effective differentiation among the six species studied. Compared with single-mode sensing arrays based on multiple receptors, this method only requires the preparation of a single nanomaterial, which produces two signal outputs for the identification of multiple bacteria with better differentiation. It can distinguish not only multiple pathogenic bacteria but also Gram-negative and Gram-positive bacteria, and, more importantly, it can perform preliminary discrimination of unknown samples.

Applications of nanomaterials as treatments and diagnostic biosensors in microbial infections

“…Because different BA−GMNPs@bacterial complexes differed in resisting assembly and producing different colorimetric and photothermal response signals, the unique molecular fingerprint of each bacterium can be obtained through the linear discriminant analysis of the response pattern. 84…”

“…A colorimetric and photothermal dual‐mode sensor array based on boronic acid‐functionalized Au−Fe 3 O 4 nanoparticles (BA–GMNPs) is used to differentiate multiple pathogenic bacteria. Because different BA−GMNPs@bacterial complexes differed in resisting assembly and producing different colorimetric and photothermal response signals, the unique molecular fingerprint of each bacterium can be obtained through the linear discriminant analysis of the response pattern 84 …”

Multiple-Emitting Luminescent Metal–Organic Framework as an Array-on-a-MOF for Rapid Screening and Discrimination of Nitroaromatics

“…Multichannel sensing device, which integrates multiple sensing units in a single sensor, has recently attracted increasing attention because it can achieve multidimensional information acquisition in a single matrix. ,, Nowadays, multichannel sensors incorporating fluorescence and other transducer channels (e.g., absorbance, phosphorescence, electrochemiluminescence, conductivity, etc.) in a single molecule (i.e., lab-on-a-molecule) or nanoparticle (i.e., lab-on-a-nanoparticle) have already been applied in several array discrimination tasks. ,− Nevertheless, most reported multichannel sensors still need repeated measurements and even various instruments and operational conditions to accomplish the detection of analytes as their signal units commonly have different transduction sources. ,,, Multitarget array sensing in a single matrix utilizing single fluorescence is still a challenge.…”

Hydrogen Bonding-Induced Aggregation of Chiral Functionalized AuNS@Ag NPs for Photothermal Enantioanalysis

“…This will result in selective and sensitive modulation performance for the photothermal effect of the sensing system. By mediating the conversion of light-to-heat energy and associated temperature changes in the system, this process can achieve high selectivity and ultrasensitive detection of trace samples. − Notably, this convenient and practical strategy has not been reported in the field of enantiomeric recognition. Thus, utilizing noble metal NPs and their photothermal properties holds promise for improving enantioselectivity and sensitivity in chiral sensing applications.…”