(170e) Real-Time Monitoring of Biomass Accumulation with Surface Plasmon Resonance Imaging (SPRi) Sensor

In this study Surface Plasmon Resonance imaging was used to real-time monitor the effect of different surface coatings on prevention of initial attachment and further growth of Staphylococcus aureus.  SPRi provides highly sensitive and label-free technique to study the biological interactions on the sensor surface. The sensor is connected to a fluidic flow system; this allows running fluid throughout the entire experiment to mimic the real environment for bacterial growth. SPRi consists of high refractive index glass prism coated with 50nm of Gold as the sensor surface.

First the PDMS made chamber was placed on the gold surface, then the surface was coated with Casein and Bovine Serum Albumin (BSA) at the same time. Staphylococcus aureus was initially inoculated in 6mL of Lycogeny Broth (LB) for 18 hours to reach a stationary growth phase. Then this media was diluted to 1:100 (v:v) ration in fresh LB. 400uL of this bacteria media was placed in the chamber. Then the whole setup was placed in the Device and the experiment was run for 24 hours. The CCD camera provides images from the surface each three seconds which allows monitoring the entire surface as bacteria grow on it. The results show that casein prevented biofilm formation for up to 24 hours. However BSA only prevented bacterial growth for the first 6 hours.