Biocompatible smart micro/nanorobots for active gastrointestinal tract drug delivery

ABSTRACT

Introduction

Oral delivery is the most commonly used route of drug administration owing to good patient compliance. However, the gastrointestinal (GI) tract contains multiple physiological barriers that limit the absorption efficiency of conventional passive delivery systems resulting in a low drug concentration reaching the diseased sites. Micro/nanorobots can convert energy to self-propulsive force, providing a novel platform to actively overcome GI tract barriers for noninvasive drug delivery and treatment.

Areas covered

In this review, we first describe the microenvironments and barriers in the different compartments of the GI tract. Afterward, the applications of micro/nanorobots to overcome GI tract barriers for active drug delivery are highlighted and discussed. Finally, we summarize and discuss the challenges and future prospects of micro/nanorobots for further clinical applications.

Expert opinion

Micro/nanorobots with the ability to autonomously propel themselves and to load, transport, and release payloads on demand are ideal carriers for active oral drug delivery. Although there are many challenges to be addressed, micro/nanorobots have great potential to introduce a new era of drug delivery for precision therapy.

KEYWORDS:

• Gastrointestinal tract
• physiological barriers
• micro/nanorobots
• drug delivery
• precision therapy

Article highlights

• The biochemical barrier, mucus barrier, and epithelial barrier are the main physiological barriers in the GI tract. To design micro/nanorobots that are capable of adapting to the human GI tract, one must consider these complex physiological environments.

• The latest advances in micro/nanorobots for active oral drug delivery are highlighted and discussed.

• Micro/nanorobots have the ability of self-propulsion, which provides new opportunities to overcome GI tract barriers to improve oral drug absorption and therapeutic bioavailability.

• The challenges and future prospects of micro/nanorobots for oral drug delivery are discussed.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This work was supported by the National Key Research and Development Program of China (2022YFC2402400), the National Natural Science Foundation of China (82302374, 81971749, 82303768), Guangdong Provincial Key Area R&D Program (2020B1111540001), the Natural Science Foundation of Guangdong Province (2022A1515010780), Shenzhen Science and Technology Program (JCYJ20200109114616534, JCYJ20210324101807020), and Guangdong Basic and Applied Basic Research Foundation (2022A1515111168).