Rapid Detection of Pathogenic Bacteria and Screening of Phage-Derived Peptides Using Microcantilevers

Abstract

We report the use of an array of microcantilevers to measure the specific binding of Salmonella to peptides derived from phage display libraries. Selectivity of these phage-derived peptides for Salmonella spp. and other pathogens ( Listeria monocytogenes and Escherichia coli ) are compared with a commercially available anti- Salmonella antibody and the antimicrobial peptide alamethicin. A Langmuir isotherm model was applied to determine the binding affinity constants of the peptides to the pathogens. One particular peptide, MSal 020417, demonstrated a higher binding affinity to Salmonella spp. than the commercially available antibody and is able to distinguish among eight Salmonella serovars on a microcantilever. A multiplexed screening system to quickly determine the binding affinities of various peptides to a particular pathogen highly improves the efficiency of the peptide screening process. Combined with phage-derived peptides, this microcantilever-based technique provides a novel biosensor to rapidly and accurately detect pathogens and holds potential to be further developed as a screening method to identify pathogen-specific recognition elements.

GaAs/AlGaAs heterostructure based photonic biosensor for rapid detection of Escherichia coli in phosphate buffered saline solution

“…While traditional bacteria detection techniques involving culture-based methods [4] are sensitive and relatively inexpensive [2], they are time-consuming and labour intensive [5][6][7]. The polymerase chain reaction (PCR) [8] offers considerable benefits over culture based methods including rapidity and equivalent sensitivity; however, the complexity of this technique and the requirement of highly qualified personnel for both sample preparation and interpretation make it unattractive for many users [9].…”

“…Automated PCR systems are expensive and target a limited number of microorganisms. Piezoelectric biosensors [10] hold good potential for detection of food-born and water-born microorganisms, but they are affected by relatively low sensitivity [7]. Electrochemical impedance spectroscopy (EIS) represents a sensitive approach to detect pathogenic microorganisms with a low limit of detection and a large linear range [11][12][13].…”

Cantilevers for biological monitoring: opportunities for classical and quantum physics

“…This flexibility and the corresponding sensitivity are the crucial and fundamental properties that govern how these cantilever sensors function. Nowadays, besides single cantilever sensors [15], arrays with multiple cantilevers are used by various groups [16][17][18][19] (see Figure 1(B)). An important advantage of multiple cantilevers, which was recognised early on [4], is that each cantilever can be coated differently, which enables sensing and monitoring of various different analytes simultaneously.…”

“…This model has been adapted to describe the adsorption of analytes in solution to immobilised targets on the cantilever surface. It has been found to model very well the experimentally obtained binding curves and is consequently used widely to characterise the binding events and to derive surface equilibrium dissociation constant K d [8,16,17,22,52,57,59,63,77,78].…”

Droplet microfluidics for kinetic studies of viral fusion

“…Droplet-based microfluidics, in which droplets of sub-nanoliter volumes are generated and used as individual chemical reactors, has allowed a wide range of biomedical applications 1 such as digital polymerase chain reaction (PCR), 2 rapid pathogen detection, 3 and antibiotics screening. 4 Droplet-based microfluidic approaches promise increased throughput, reduced usage of reactants, and the ability to rapidly execute complex workflows involving multiple steps.…”