A remotely operated drug delivery system with dose control

Abstract

On demand" implantable drug delivery systems can provide optimized treatments, due to their ability to provide targeted, flexible and precise dose release. However, two important issues that need to be carefully considered in a mature device include an effective actuation stimulus and a controllable dose release mechanism. This work focuses on remotely powering an implantable drug delivery system and providing a high degree of control over the released dose. This is accomplished by integration of a resonance-based wireless power transfer system, a constant voltage control circuit and an electrolytic pump. Upon the activation of the wireless power transfer system, the electrolytic actuator is remotely powered by a constant voltage regardless of movements of the device within an effective range of translation and rotation. This in turn contributes to a predictable dose release rate and greater flexibility in the positioning of external powering source. We have conducted proof-of-concept drug delivery studies using the liquid drug in reservoir approach and the solid drug in reservoir approach, respectively. Our experimental results demonstrate that the range of flow rate is mainly determined by the voltage controlled with a Zener diode and the resistance of the implantable device. The latter can be adjusted by connecting different resistors, providing control over the flow rate to meet different clinical needs. The flow rate can be maintained at a constant level within the effective movement range. When using a solid drug substitute with a low solubility, solvent blue 38, the dose release can be kept at 2.36 µg/cycle within the effective movement range by using an input voltage of 10V pp and a load of 1.5 kΩ, which indicates the feasibility and controllability of our system without any complicated closed-loop sensor.

Miniaturized Drug Delivery System for Biomedical Applications

“…Successful delivery of about 3.8 µL red dye through microneedles was achieved using wireless inductive powering at 10 mm distance between the transmitter and receiver. This delivery system showed a compromise between the device size, dose volume, power consumption, and design flexibility, comparing to previous works in [6][7][8] and [10][11].…”

“…Combined with Parylene C's biocompatibility, they act as a diaphragm isolating the drug reservoir from the pumping source preventing degradation and pH changes from water exposure [6]. Due to these pumps' minimal power requirements, wireless inductive powering units can be installed to achieve wireless actuation [10][11]. With an electromagnetic field from a transmitting coil, a current is induced in the receiving coil driving the electrolytic reaction in the pump.…”

“…With an electromagnetic field from a transmitting coil, a current is induced in the receiving coil driving the electrolytic reaction in the pump. Past works have applied similar concepts, reporting drug delivery systems integrated with electrochemical micro pumps [6][7][8], [10][11].…”

Biocompatible 3D Printed Microneedles for Transdermal, Intradermal, and Percutaneous Applications

“…In this regard, recent advancements in microtechnology have helped to make remarkable progress in health‐care monitoring and disease therapy. Examples are miniaturized laboratories (Lab‐on‐Chip, LoC) and microsystems able to sense, diagnose, and deliver a drug to the specific target region . In this context, the implementation of MNs for drug delivery is one of the most prominent developments in the drug administration field, due to their painless and minimally invasive operation.…”

A Resonant Coupling Power Transfer System Using Two Driving Coils

“…The WPT systems also exhibits great potential to be combined with wireless communication electronics for data transmission [7][8][9]. In particular, resonance-based WPT (R-WPT) systems [10][11][12] that use resonant coupling coils can achieve high (e.g., 78.6% at distance of 10 mm [11]) power transfer efficiency (PTE) [13,14]. Different from an inductive coupling power transfer technique [15], the R-WPT utilizes a capacitor and an inductor to form a LC resonant circuit.…”