Magnetostrictive particle based biosensors for in situ and real‐time detection of pathogens in water

Abstract

Biosensors for in situ detection of pathogenic bacteria in liquid are developed using magnetostrictive particles (MSP) as the sensor platform. The sensing elements used are phage E2 against Salmonella typhimurium, monoclonal antibody against Listeria monocytogenes, polyclonal antibody against Escherichia coli, and polyclonal antibody against Staphylococcus aureus, respectively. These biosensors were characterized in cultures with different populations ranging from 5 × 10(1) to 5 × 10(8) cfu/mL. It is found that the MSP-based biosensors work well in water and have a rapid response with a response time in minutes, which makes the MSP-based sensors suitable for in situ and real-time detection of pathogenic bacteria in liquid. The experimental results show that all MSP-phage and MSP-antibody biosensors in size of 1.0 mm × 0.3 mm × 15 µm exhibit a detection limit better than 100 cfu/mL. Based on the Hill plot, it is concluded that each bacterial cell is bound onto the sensor surface through about four-to-five sites. When the cultures with low population (<10(6) cfu/mL) are tested, both MSP-phage and MSP-antibody sensors exhibit the similar response. However, the phage-MSP sensors exhibit a higher capability in the capture of target bacterial cell.

Numerical Study on Mass Sensitivity of Magnetoelastic Biosensors with Concentrated Mass Load under Different Resonance Modes

“…, 1) on the sensor. We find that 2 max /(∑ 101 =1 2 /101) ≈ 2 and the value is very close to that of ,max / , = 2. Therefore, it is believed that mass sensitivity for uniform mass load is the average contribution of 2 from all the loading points; that is, To investigate the effect of magnitude of mass load on mass sensitivity, mass sensitivities under six different loading masses (i.e., 0 = /1000, 1 = /900, .…”

“…With the advantages of wireless in detection, easiness in operation, and low cost, magnetoelastic biosensors as an important type of acoustic wave devices have been widely used for the detection of pathogens like Listeria monocytogenes [1,2], Escherichia coli [1,2], Staphylococcus aureus [2], Salmonella typhimurium [2][3][4][5][6][7], Bacillus anthracis spores [7,8], Staphylococcus epidermidis [9], and other chemicals [10,11]. A magnetoelastic biosensor is typically made of a freestanding rectangular magnetoelastic strip immobilized with bioreceptors on its surface.…”

“…Mass sensitivity can be well determined if the targets (i.e., mass load) are uniformly immobilized on the whole sensor surface [1]. This kind of immobilization mode has been widely used for magnetoelastic biosensors in various applications [1][2][3][4][5][6][7][8][9][10][11]. However, recent study has shown that such immobilization mode is not the best way to obtain the optimized mass sensitivity due to the location dependence of mass sensitivity [12][13][14].…”

SEM Statistical Analyses in Management Strategies

“…Results focused on data analyses are systematically presented [114]. An empirical factor analysis was expended to investigate the sustainable innovation effects in e-purchase management strategies [115] [116]. Consequently, SEM was utilized to build a model for sorting out the individual models interrelationships [117] [118].…”

Effect of Distributed Mass on the Node, Frequency, and Sensitivity of Resonant-Mode Based Cantilevers

“…In the past decades, resonant-mode based cantilevers have shown high potential for the bio/chemical sensing applications [ 1 , 2 , 3 , 4 ]. The working principle is based on the shift in the resonant frequency due to the mass load caused by the specific binding of targets (i.e., microorganism, chemicals) on their surfaces [ 5 , 6 , 7 ]. For any type of sensors, sensitivity is an important parameter to characterize their performance.…”