Abstract
The pharmacologic effect of an antibiotic is directly related to its unbound concentration at the site of infection. Most of the commercial antibiotics have been selected in part for their low propensity to interact with serum proteins. These "non-specific" interactions are classically evaluated by measuring the minimal inhibitory concentration in the presence of serum. As higher throughput technologies tend to lose information, surface plasmon resonance (SPR) is emerging as an informative medium-throughput technology for hit validation. Here we show that SPR is a useful automatic tool to quantify the interaction of model antibiotics with serum proteins, and delivers precise real-time kinetic data on this critical parameter.