Wireless programmable electrochemical drug delivery micropump with fully integrated electrochemical dosing sensors

Abstract

We present a fully integrated implantable electrolysis-based micropump with incorporated EI dosing sensors. Wireless powering and data telemetry (through amplitude and frequency modulation) were utilized to achieve variable flow control and a bi-directional data link with the sensors. Wireless infusion rate control (0.14-1.04 μL/min) and dose sensing (bolus resolution of 0.55-2 μL) were each calibrated separately with the final circuit architecture and then simultaneous wireless flow control and dose sensing were demonstrated. Recombination detection using the dosing system, as well as, effects of coil separation distance and misalignment in wireless power and data transfer were studied. A custom-made normally closed spring-loaded ball check valve was designed and incorporated at the reservoir outlet to prevent backflow of fluids as a result of the reverse pressure gradient caused by recombination of electrolysis gases. Successful delivery, infusion rate control, and dose sensing were achieved in simulated brain tissue.

Flexible fiber-based optoelectronics for neural interfaces

“…Likewise, Utah arrays and Michigan probes have been outfitted with microfluidic channels to allow for chemical delivery. 216,217 Notably, it was possible to monitor electrical and chemical signals via the same electrodes. Suzuki and colleagues developed soft parylene-C based neural probes that integrated electrodes and microfluidic channels to target peripheral nerve activity ( Fig.…”

Multifunctional Neural Interfaces for Closed‐Loop Control of Neural Activity

“…In addition to there being limited space to include a small reservoir, it is also important to ensure the reservoir can safely contain the liquids. Several microfabrication strategies have been employed to address this issue, such as check valves, hermetic sealing, and materials to prevent fluid evaporation [226][227][228] .…”

A modular microreservoir for active implantable drug delivery

“…These microsystems have been employed in various applications such as ophthalmology [7][8][9][10][11][12][13], oncology [14][15][16], interventional cardiology [17][18][19][20], precocious puberty [7], acromegaly [21], Hepatitis C [21][22][23], prostate cancer [24][25][26], pain indications [27], type 2 diabetes and Hepatitis [28][29][30][31][32]. In contrast, active implantable drug delivery systems are driven by mechanical pumping [33,34], electrolysis [35], and other actuation methods, which enable the patient or physician to start/modify/stop drug release interactively. These systems have been used for emergency care [36,37], treatment of ocular diseases [38,39] and cancer [40], and general application in small animals [41].…”