A Wireless Wearable Platform for Intravenous Drug Self-Administration in Freely Behaving Rats

Jeong, E. Y.; Teague, C. D.; Reimert, A.; Cho, S.; Lee, J.; Althoff, T.; Lin, K.; Nair, M.; Leong, T.; Silva, E.; Parker, K. E.; Cahill, C. M.; McCall, J. G.; Jeong, J.-W.; Massaly, N.

doi:10.64898/2026.09.08.750146

bioRxiv · 10.64898/2026.09.08.750146

A Wireless Wearable Platform for Intravenous Drug Self-Administration in Freely Behaving Rats

Jeong, E. Y.·Teague, C. D.·Reimert, A.·Cho, S.·Lee, J.·Althoff, T.·Lin, K.·Nair, M.·Leong, T.·Silva, E.·Parker, K. E.·Cahill, C. M.·McCall, J. G.·Jeong, J.-W.·Massaly, N.

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Abstract

Studying how drugs act on neuronal circuits requires delivering them with temporal precision while behavior proceeds undisturbed, a combination that tethered infusion systems cannot provide. We developed WEARIT (Wireless Equipment for Autonomous Rat Infusion Tasks), a wearable, tetherless infusion platform that gives freely moving rats intravenous access under either remote or closed-loop operant control. The device houses a reservoir, miniaturized pump, rechargeable battery and Bluetooth circuitry in a 3D-printed enclosure worn on the back. By measuring spontaneous locomotion, amphetamine-induced hyperlocomotion and food-reinforced operant responding, we show that WEARIT leaves these behaviors unchanged. Remotely triggered fentanyl infusions yielded reliable delivery with physiological responses confirmed by pulse oximetry, and self-administration acquisition and dose-response functions were comparable to conventional tethered systems. WEARIT removes a longstanding constraint on intravenous pharmacology, opening self-administration paradigms to naturalistic and enriched environments and to concurrent imaging or optogenetic manipulation of the circuits engaged by drug reinforcement.

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Jeong, E. Y., Teague, C. D., Reimert, A., Cho, S., Lee, J., Althoff, T., Lin, K., Nair, M., Leong, T., Silva, E., Parker, K. E., Cahill, C. M., McCall, J. G., Jeong, J.-W., Massaly, N.. 2026-09-14. A Wireless Wearable Platform for Intravenous Drug Self-Administration in Freely Behaving Rats. https://doi.org/10.64898/2026.09.08.750146

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