Control, communication and monitoring of intravaginal drug delivery in dairy cows

• Published in: International journal of pharmaceutics Vol. 282; no. 1; pp. 35 - 44
• Main Authors: Cross, Peter S., Künnemeyer, Rainer, Bunt, Craig R., Carnegie, Dale A., Rathbone, Michael J.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 10.09.2004; Elsevier
• Subjects: Administration, Intravaginal; Animals; Biological and medical sciences; Body Temperature - physiology; Calibration; Cattle; Controlled release; Cow; Drug delivery; Estrous Cycle - physiology; Female; General pharmacology; Infusion Pumps, Implantable; Medical sciences; Microcomputers; Oestrus; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Radio; Software; Syringes; Telemetry; Telemetry - methods; Temperature; Oestrus; Drug delivery; Cow; Radio; Telemetry; Controlled release; Drug; Delivery system; Pharmaceutical technology; Intravaginal administration; Controlled release form; Dosage form; Communication
• ISSN: 0378-5173; 1873-3476
• DOI: 10.1016/j.ijpharm.2004.05.023

We present the design of an electronically controlled drug delivery system. The intravaginally located device is a low-invasive platform that can measure and react inside the cow vagina while providing external control and monitoring ability. The electronics manufactured from off the shelf components occupies 16 mL of a Theratron ™ syringe. A microcontroller reads and logs sensor data and controls a gascell. The generated gas pressure propels the syringe piston and releases the formulation. A two way radio link allows communication between other devices or a base station. Proof of principle experiments confirm variable-rate, arbitrary profile drug delivery qualified by internal sensors. A total volume of 30 mL was dispensed over a 7-day-period with a volume error of ±1 mL or ±7% for larger volumes. Delivery was controlled or overridden via the wireless link, and proximity to other devices was detected and recorded. The results suggest that temperature and activity sensing or social grouping determined via proximity can be used to detect oestrus and trigger appropriate responses.