Is what you eat and drink safe? detection and identification of microbial contamination in foods and water

Abstract

Current technologies for assessing the microbial load in food and water require cellular outgrowth to increase the cell count to a detectable level. This step therefore makes real-time assessment of microbial loads impossible. To circumvent this problem, we have developed a high-sensitivity, multiwavelength fluorescence detector and signal-collection and processing software. This detection system enables one to distinguish between abiotic matter, sporulated bacteria, vegetative bacteria, dead bacteria, and other biomaterials containing aromatic amino acids. Our detection limit is in the 10-100 cell/cm 2 range (or per cm 3 if bulk aqueous samples are used), and there is no sample contact. To supplement this detection system, we have developed a variety of ligands, including hemin derivatives, peptides, glycoconjugates, and siderophores, for cell capture to circumvent problems associated with antibodies. These materials are tethered to disposable surfaces (glass, plastics) in arrays for use in capturing biomaterials (e.g., live bacterial cells, dead cells, spores, and toxins); identification is based on which sector of an array it binds to. The detection system can serve as a reader for these coated materials, and variants have been tested for use in scanning food surfaces and food wash water.

A Novel Tris(2-aminoethyl)amine Based Tripodal Ligand: Synthesis and Solution Coordination Studies with Trivalent Iron and Chromium

“…In these aspects, low molecular weight naturally occurring biomolecules, siderophores, have capability to bind with iron with high affinity and specificity. Nowadays, iron uptake by those biomolecules is serving as a novel platform for various applications, based on iron uptake mechanism such as drug delivery system [5,6], detection of microorganisms [7,8], and capture and accumulation of actinide elements [9][10][11]. In order to put some appropriate solution, synthesis of novel molecules is required which may be considered against intoxication of aforesaid metals in the biological systems and may also be used for developing some sought probes for the detection of these metals in trace quantity if present in the surrounding environment.…”

Continuous Real-time Detection of Microbial Contamination in Water using Intrinsic Fluorescence

“…We were able to quantify the total microbial load and differentiate between dead and live bacteria for water-monitoring purposes. This technology, used together with direct microbial cell capture onto a ligand-coated surface may allow us to monitor our drinking water along the distribution water system continuously and determine the presence of pathogenic microbes [11,13,18] in real-time.…”

“…There are technologies that can be used simultaneously with the intrinsic fluorescence technology for identification of microorganisms of interest. One such method that has been demonstrated is the use of cell-capture technology using surfacebound ligands [13,18].…”

Adsorption Behavior of Microbes on a QCM Chip Modified with an Artificial Siderophore–Fe3+ Complex

“…The use of siderophores as agents for the immobilization of microbes is one of the most promising methods for the adsorption and detection of microbes. − Our group has investigated the preparation of artificial siderophores − as structural and functional model compounds for natural siderophores. − We also have recently reported the immobilization of microbes using an artificial siderophore-modified substrate …”