Recent advances of controlled drug delivery using microfluidic platforms

Abstract

Conventional systematically-administered drugs distribute evenly throughout the body, get degraded and excreted rapidly while crossing many biological barriers, leaving minimum amounts of the drugs at pathological sites. Controlled drug delivery aims to deliver drugs to the target sites at desired rates and time, thus enhancing the drug efficacy, pharmacokinetics, and bioavailability while maintaining minimal side effects. Due to a number of unique advantages of the recent microfluidic lab-on-a-chip technology, microfluidic lab-on-a-chip has provided unprecedented opportunities for controlled drug delivery. Drugs can be efficiently delivered to the target sites at desired rates in a well-controlled manner by microfluidic platforms via integration, implantation, localization, automation, and precise control of various microdevice parameters. These features accordingly make reproducible, on-demand, and tunable drug delivery become feasible. On-demand self-tuning dynamic drug delivery systems have shown great potential for personalized drug delivery. This review presents an overview of recent advances in controlled drug delivery using microfluidic platforms. The review first briefly introduces microfabrication techniques of microfluidic platforms, followed by detailed descriptions of numerous microfluidic drug delivery systems that have significantly advanced the field of controlled drug delivery. Those microfluidic systems can be separated into four major categories, namely drug carrier-free micro-reservoir-based drug delivery systems, highly integrated carrier-free microfluidic lab-on-a-chip systems, drug carrier-integrated microfluidic systems, and microneedles. Microneedles can be further categorized into five different types, i.e. solid, porous, hollow, coated, and biodegradable microneedles, for controlled transdermal drug delivery. At the end, we discuss current limitations and future prospects of microfluidic platforms for controlled drug delivery.

Nanofiber‐Based Hydrogels: Controllable Synthesis and Multifunctional Applications

“…Conventional medication ways, such as intravenous injection and oral administration, usually result in rapid drug degradation and excretion during the circulation process in the body, thereby leaving a small amount of drug that can play therapeutic effects at the pathological sites. Controlled drug delivery has become a promising approach to resolve this problem, because drugs can be effectively delivered to the target sites at controlled release rate, thus greatly enhancing the drug efficacy and decreasing the unwanted side effects . In recent years, self‐assembling peptide NFHGs have gained increasing attentions and have been seen as a promising candidate for the controllable drug delivery, owing to their specific peptide–drug interactions, target recognitions, good biocompatibility and biodegradability …”

“…Controlled drug delivery has become a promising approach to resolve this problem, because drugs can be effectively delivered to the target sites at controlled release rate, thus greatly enhancing the drug efficacy and decreasing the unwanted side effects. [105,106] In recent years, self-assembling peptide NFHGs have gained increasing attentions and have been seen as a promising candidate for the controllable drug delivery, owing to their specific peptide-drug interactions, target recognitions, good biocompatibility and biodegradability. [58] Hartgerink and co-workers developed a novel injectable nanofiber-based hydrogel for the stem cell secretome delivery by self-assembling MDPs of E 2 (SL) 6 E 2 GRGDS.…”

Synthesis of a novel copolymer using glycogen and poly(lactide) as a carrier of dual drugs—ornidazole and ofloxacin

“…Administration of medicines should always maintain a therapeutic window through which the drug concentration would be at a certain value at the desired site of action: below which it is not effective, while above it shows toxicity . This typical necessity always demands an efficient carrier for targeted delivery of drugs.…”

Optoregulated Drug Release from an Engineered Living Material: Self‐Replenishing Drug Depots for Long‐Term, Light‐Regulated Delivery

“…However, their increased complexity reduces their drug‐loading capacity, complicates industrial scale‐up, and increases cost of production . These challenges have triggered new design concepts, outside the box, to move therapeutic administration into a new era . From a bioengineering perspective, the idea of “living therapeutics,” i.e., the use of metabolic engineered therapeutic bacteria to deliver the drug in vivo seems particularly attractive .…”

“…[1,3] These challenges have triggered new design concepts, outside the box, to move therapeutic administration into a new era. [4][5][6] From a bioengineering perspective, the idea of "living therapeutics," i.e., the use of metabolic engineered therapeutic bacteria to deliver the drug in vivo seems particularly attractive. [5,6] The ability to synthesize the drug at the application site (i.e., in the body) is appealing as it avoids previous drug manufacture and encapsulation steps, overcomes drug stability issues, and could facilitate longterm therapeutic treatments.…”