Open flow microperfusion (OFM) is an in-vivo sampling technique used to collect tissue-specific concentrations of molecules regardless of molecular weight or lipophilicity. Continuously and repeatedly sample bound and unbound drug, neurotransmitters, antibodies and more! OFM reduces cost and development time by providing the pharmacological profile of a drug at an earlier phase in drug development. Combine with BASi’s Movement Responsive Caging System, RaturnTM, and Fraction Collector for a hands-off approach to sample collection in awake, freely moving animals.