Related Experiment Video
Updated: Aug 3, 2026
09:11
Alternating Magnetic Field-Responsive Hybrid Gelatin Microgels for Controlled Drug Release
Published on: February 13, 2016
9.9K
On-demand electrochemically controlled compound release from an ultrasonically powered implant
Max L Wang1, Christian F Chamberlayne2, Haixia Xu3
1Department of Electrical Engineering, Stanford University Stanford CA USA arbabian@stanford.edu.
RSC Advances
|September 12, 2022
Summary
Researchers developed a novel on-demand drug delivery system using electroresponsive polypyrrole nanoparticles and an ultrasonically powered implant. This wireless system enables controlled release of negatively charged drugs, minimizing side effects.
Area of Science:
- Biomedical Engineering
- Materials Science
- Pharmacology
Background:
- On-demand drug delivery systems offer therapeutic advantages by reducing dosage and side effects.
- Wireless implants enhance controlled drug release capabilities.
- Passive leakage from drug delivery systems is a significant challenge.
Purpose of the Study:
- To develop a novel on-demand drug release system for negatively charged compounds.
- To create an ultrasonically powered implant for wireless control of drug delivery.
- To evaluate the release kinetics of the system in vitro and in vivo.
Main Methods:
- Fabrication of a modified electroresponsive polypyrrole nanoparticulate film.
- Design and integration of an mm-sized, ultrasonically powered implant.
- In vitro and in vivo characterization of fluorescein release kinetics in mice.
Main Results:
- Demonstrated on-demand release of fluorescein from the novel nanoparticulate film.
- Successfully controlled drug release wirelessly using the ultrasonically powered implant.
- Validated the system's feasibility for in vivo applications.
Conclusions:
- The developed system enables wireless, on-demand drug delivery for negatively charged compounds.
- The modified polypyrrole film minimizes passive leakage, improving drug retention.
- Ultrasonically powered implants offer a viable solution for controlled therapeutic applications.
Related Concept Videos
01:19Modified-Release Drug Delivery Systems: Rate-Programmed II
Rate-programmed drug delivery systems release drugs in a controlled manner to maintain therapeutic levels. Three main designs include reservoir, matrix, and hybrid systems.Reservoir systems consist of a drug core enclosed within a membrane that controls drug release. In non-swelling reservoir systems, polymers like ethyl cellulose or polymethacrylates are used. These do not hydrate in aqueous media and control release through membrane thickness, porosity, or insolubility. This type includes...
01:23Modified-Release Drug Delivery Systems: Classification
Modified-release drug delivery systems improve drug efficacy and minimize side effects by controlling the rate and location of drug release. These systems fall into three categories: rate-programmed, stimuli-activated, and site-targeted.Rate-programmed systems release drugs at a predetermined rate, maintaining consistent therapeutic levels and reducing fluctuations that could lead to toxicity or subtherapeutic effects. These systems use polymeric matrices, reservoir-based designs, or osmotic...
01:22Modified-Release Drug Delivery Systems: Rate-Programmed I
Rate-programmed drug delivery systems (DDS) are designed to release drugs at specific, controlled rates to maintain consistent therapeutic levels. These systems are categorized based on their release mechanisms, including dissolution-controlled DDS, diffusion-controlled DDS, and combined dissolution-diffusion-controlled DDS.In dissolution-controlled DDS, the release rate depends on the slow dissolution of the drug itself or the surrounding matrix. Drugs with inherently slow dissolution rates,...
01:30Modified-Release Drug Delivery Systems: Stimuli-Activated
Stimuli-activated drug delivery systems are designed to release drugs in response to specific physical, chemical, or biological stimuli. These systems often utilize hydrogels—three-dimensional, hydrophilic polymer networks capable of swelling in aqueous environments and retaining significant fluid volumes. Upon exposure to particular stimuli, these hydrogels undergo structural transitions that allow the embedded drug to be released. Due to this adaptive behavior, such systems are also called...
01:21Intrauterine Drug Delivery Systems
Controlled-release systems for intravaginal and intrauterine drug delivery have been developed primarily for the administration of contraceptive steroid hormones. These delivery routes circumvent first-pass hepatic metabolism, thereby enhancing bioavailability and allowing for reduced systemic dosages compared to oral administration. Such approaches contribute to improved therapeutic efficacy and patient compliance, particularly in long-term contraceptive regimens.Intravaginal Drug Delivery...