(338b) A Lab-on-a-Chip Platform of Mono-and Poly-Microbial Biofilms for High-Throughput Downstream Applications

Authors: 
Ramasubramanian, A., University of Texas at San Antonio
Srinivasan, A., University of Texas at San Antonio
Lopez-Ribot, J., University of Texas at San Antonio
Leung, K., U.S. Army Institute of Surgical Research
BACKGROUND:Most hospital-acquired infections are caused by microbial colonization that is polymicrobial in nature. Some adapt to biofilm mode of growth which complicates treatment and contributes to unacceptably high mortality rates. These manifestations are common in patients with compromised immunity. Hence there is a dire need for novel and effective antimicrobial agents in eradicating pathogenic communities and limit the emergence of drug-resistant strains.

METHODS: We have developed a novel lab-on-a-chip platform of mono-and poly-microbial biofilms of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans for high-throughput antimicrobial screening. The nano-biofilm chip (nBioChip) is robotically printed, robustly handled and scanned using a standard microarray reader. The platform is â??trulyâ? high-throughput and serves as a rising alternative to conventional modes of drug screening.

RESULTS: The biofilm chip consisted of identical nano-biofilms embedded in a hydrogel and exhibited resistance to washing steps involved in the drug screening assay. The biofilm, although nano-scale in nature, demonstrated i) the morphology and three-dimensional architecture of a macroscopic biofilm; ii) elevated drug resistance to antibiotic treatment; and iii) synthesized idiosyncratic exo-polymeric matrix material of a true biofilm. Based on our results, the nBioChip can generate reliable high-throughput antimicrobial susceptibility testing (HT-AST) in 12-18 h. The chip serves as a proof-of-concept platform for high-throughput drug screening against any microorganism and furthers the understanding of microbial interactions in mixed-species communities.