Focus on quantum dots as potential fluorescent probes for monitoring food toxicants and foodborne pathogens

Abstract

Water-soluble quantum dots (QDs) are fluorescent semiconductor nanoparticles with narrow, very specific, stable emission spectra. Therefore, the bioconjugation of these QDs for biological fluorescent labeling may be of interest due to their unique physical and optical properties as compared to organic fluorescent dyes. These intrinsic properties of QDs have been used for the sensitive detection of target analytes. From the viewpoint of ensuring food safety, there is a need to develop rapid, sensitive and specific detection techniques to monitor food toxicants in food and environmental samples. Even trace levels of these toxicants can inadvertently enter the food chain, creating severe health hazards. The present review emphasizes the application of water-soluble bioconjugated QDs for the detection of food contaminants such as pesticides, pathogenic bacterial toxins such as botulinum toxin, enterotoxins produced by Staphylococcus aureus, Escherichia coli, and for the development of oligonucleotide-based microarrays. This review also emphasizes the application of a possible resonance energy transfer phenomenon resulting from nanobiomolecular interactions obtained through the bioconjugation of QDs with biomolecules. Furthermore, the utilization of significant changes in the spectral behavior of QDs (attributed to resonance energy transfer in the bioconjugate) in future nanobiosensor development is also emphasized.

Nanotechnology in the Development of Novel Functional Foods or their Package. An Overview Based in Patent Analysis

“…However, conventional methods such as spectrophotometry and chromatography, PCR, culture and colony counting, immunological techniques or fluorescence based assays using organic dye molecules, require skilled personnel and are time consuming, laborious and expensive. Also, they do not always produce accurate results, especially when the analyses are performed rapidly and cost-cutting is paramount [76].…”

“…For instance, use of carbon nanotube's conductance change provoked by the presence of target analytes, such as pesticides, toxins, or contaminants, has been patented to detect these species in solution, eliminating the need for immobilizing the analyte on a support [78]. Quantum dots, meanwhile, are fluorescent semiconductor nanoparticles with narrow, very specific and stable emission spectra constructed from elements of Groups II-VI, III-V and IV-VI of the periodic table [79]. Quantum dots-based sensor arrays have been reported for differentiating the strain of a variety of biological molecules including bacteria, spores, fungi, viruses, and disease-causing prions [80].…”

Application of Modern Biosensors Methods in Ecotoxicological Monitoring of Some Toxins of Natural (Micotoxins) and Antropogenic (Pesticides) Origin. Part 2. Pesticides

“…Нанотрубки (CNTs) також є багатообіцяючим інструментом підвищення ефективності біосенсорів для визначення пес-тицидів [92]. Квантові точки (QDs) використо-QDs) використо-) використо-вували також в технології мікроматриць для мультикомплексного аналізу пестицидів вна-слідок їх вузьких, високоспецифічних і стій-ких спектрів емісії [93].…”

Evolution and Expectations of Enzymatic Biosensors for Pesticides

“…Actually, water-soluble bioconjugated quantum dots (QDs) are being investigated as an option to detect pesticides in food formulations and drinking water (Vinayasa & Thakur, 2010). A quantum dot is a portion of semiconductor material whose excitons are confined in all three spatial dimensions.…”