Microneedle-based drug delivery: studies on delivery parameters and biocompatibility
Yan Wu1, Yuqin Qiu, Suohui Zhang
1Laboratory of Organic Optoelectronic Functional Materials and Molecular Engineering, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100080, People's Republic of China.
Biomedical Microdevices
|March 8, 2008
Summary
This study developed low-cost microneedles for painless drug delivery. These microneedles significantly enhance skin permeation, offering a promising new method for intradermal drug delivery systems.
Area of Science:
- Biomedical Engineering
- Drug Delivery Systems
- Nanotechnology
Background:
- Microneedles show potential for increasing intradermal drug delivery.
- Existing methods face challenges in cost and patient comfort.
- Enhanced percutaneous drug permeation is a key goal in transdermal delivery.
Purpose of the Study:
- To develop cost-effective, painless microneedle systems for enhanced intradermal drug delivery.
- To investigate the efficacy of octagonal pyramidal microneedles in improving percutaneous drug permeation.
- To evaluate the biocompatibility of the developed microneedle system.
Main Methods:
- Fabrication of octagonal pyramidal microneedles with a length of 150 µm.
- Insertion of microneedle arrays into human dermatomed skin for varying durations (5-60 s).
- Assessment of microconduit formation and drug permeation using calcein as a model drug.
Main Results:
- Microneedle insertion created microconduits (50-80 µm depth) in the skin.
- Calcein permeability coefficient increased by 10^4 to 10^5 times compared to intact skin.
- Biological evaluation confirmed the broad safety spectrum of the microneedle system.
Conclusions:
- Octagonal pyramidal microneedles effectively enhance percutaneous drug permeation.
- The developed microneedle system is a viable tool for novel intradermal drug delivery.
- Low-cost, painless microneedle technology offers significant advantages for transdermal drug administration.
Related Concept Videos
01:24Modified-Release Drug Delivery Systems: Site-Targeted
Site-targeted drug delivery systems enhance therapeutic efficacy while minimizing systemic toxicity and treatment costs. Unlike conventional methods, these systems ensure precise drug delivery, improving bioavailability and reducing side effects. Targeted drug delivery is classified into three levels. First-order targeting directs drugs to the capillary beds of specific organs or tissues. Second-order targets specific cell types, such as tumor cells, using receptor-mediated interactions.
01:24Site-Targeted Drug Delivery Systems: Polymeric Carriers
Polymeric carriers enhance targeted drug delivery by increasing efficacy while minimizing off-target effects. These carriers comprise a biodegradable polymeric backbone integrated with functional elements that enable targeting, improve physicochemical properties, and regulate drug release.Targeting MechanismsThe targeting ability of polymeric carriers is mediated by a homing device, which is a molecular recognition component designed to selectively bind to specific tissues or cells. Monoclonal...
01:16Drug Delivery: Overview
The selection of a drug's delivery route depends upon its physicochemical properties, including lipid or water solubility and ionization, as well as the therapeutic requirement, such as immediate or sustained effect. These routes can be divided into three primary categories: enteral, parenteral, and topical.
Enteral delivery involves administering drugs directly through swallowing, sublingual placement, or buccal application. Orally administered drugs predominantly navigate the gastrointestinal...
Enteral delivery involves administering drugs directly through swallowing, sublingual placement, or buccal application. Orally administered drugs predominantly navigate the gastrointestinal...
01:30Modified-Release Drug Delivery Systems: Bioavailability
Modified-release (MR) dosage forms are designed to extend drug release over time, thereby maintaining stable plasma concentrations and reducing dosing frequency. However, their bioavailability is typically below 100% due to incomplete drug release and presystemic metabolism, and limitations in drug permeability across the gastrointestinal epithelium, all of which can restrict the fraction of the drug reaching systemic circulation. Consequently, studying the in vivo bioavailability of MR...
01:22Modified-Release Drug Delivery Systems: Drug Release Characteristics
Drug release from modified-release dosage forms is designed to achieve specific therapeutic effects by controlling the rate and extent of drug release. The classification of these drug release systems is based on key pharmacokinetic assumptions: drug disposition follows first-order kinetics, drug release is the rate-limiting step in absorption, and the released drug is rapidly and completely absorbed.There are four major models of drug release patterns. The first model is the slow zero-order...
01:23Ophthalmic Drug Delivery Systems
Ophthalmic drug delivery faces major limitations due to poor absorption across the corneal membrane. This process is primarily driven by diffusion and is influenced by two main factors: the physicochemical properties of the drug and tear drainage. Most ophthalmic drugs, such as pilocarpine, epinephrine, atropine, and local anesthetics, are weak bases. They are typically formulated at an acidic pH to enhance chemical stability. However, this leads to high ionization, reducing their ability to...