# Collective Magnetic Mesoporous Silica Nanorobots for Targeted Oral Capsaicin Delivery in Colitis Intervention

## TL;DR

Researchers developed magnetic nanorobots that deliver capsaicin to the colon to treat inflammatory bowel disease more effectively.

## Contribution

A novel magnetic nanorobot system for targeted oral capsaicin delivery in colitis treatment is introduced.

## Key findings

- Capsaicin-loaded nanorobots achieved collective locomotion up to 180.7 μm/s under magnetic guidance.
- The system enables targeted drug enrichment and sustained release at colonic lesion sites.
- The nanorobots overcome millimeter-scale obstacles during movement in the gut.

## Abstract

Magnetic nanoparticles, with their excellent biocompatibility and biodegradability, serve as ideal materials for constructing targeted drug delivery systems. Iron oxide (Fe3O4) nanoparticles, controllably prepared via methods such as solvothermal synthesis, can be combined with mesoporous silica to construct magnetically steerable nanorobots. Such robots enable efficient drug loading and precise delivery. To address challenges in the treatment of Inflammatory Bowel Disease (IBD), including the significant side effects of systemic drugs and the low oral bioavailability and poor colonic targeting of novel food-derived drugs (e.g., capsaicin with anti-inflammatory activity), this study designed capsaicin-loaded iron oxide-mesoporous silica composite nanorobots (Cap-M@mSbots). Driven by a rotating gradient magnetic field of up to 80 mT, Cap-M@mSbots achieve large-scale emergent collective locomotion, with a maximum collective locomotion velocity reaching 180.7 μm/s, and are capable of long-distance movement overcoming millimeter-scale obstacles. This system can be actively propelled to colonic lesion sites under magnetic guidance, achieving targeted drug enrichment and sustained release, thereby offering a novel strategy for the targeted therapy of IBD.