Preliminary study on alginate/NIPAM hydrogel-based soft microrobot for controlled drug delivery using electromagnetic actuation and near-infrared stimulus.
Currently, microrobots are receiving attention because of their small size and motility, which can be applied to minimal invasive therapy. Additionally, various microrobots using hydrogel with the characteristics of biocompatibility and biodegradability are also being developed. Among them, microrobots that swell and deswell in response to temperature changes caused by external near infrared (NIR) stimuli, focused ultrasound, and an alternating magnetic field, have been receiving a great amount of interest as drug carriers for therapeutic cell delivery. In this study, we propose a spring type medical microrobot that can be manipulated by an electromagnetic actuation (EMA) system and respond to an external stimulus (NIR). Additionally, we verified its feasibility with regard to targeting and drug delivery. There exist various methods of fabricating a spring type microrobot. In this study, we adopted a simple method that entails using a perfluoroalkoxy (PFA) microtube and a syringe pump. Moreover, we also used a hydrogel mixture composed of natural alginate, N-Isopropylacrylamide (NIPAM) for temperature responsiveness, and magnetic nanoparticles (MNPs) for electromagnetic control. Then, we fabricated a spring type alginate/NIPAM hydrogel-based soft microrobot. Additionally, we encapsulated doxorubicin (DOX) for tumor therapy in the microrobot. To verify the feasibility of the proposed spring type hydrogel-based soft microrobot's targeting and drug delivery, we developed an EMA and NIR integrated system. Finally, we observed the swelling and deswelling of the soft microrobot under NIR stimulation and verified the EMA controlled targeting. Moreover, we implemented a control function to release the encapsulated anticancer drug (DOX) through the swelling and deswelling of the soft microrobot by NIR, and evaluated the feasibility of cancer cell therapy by controlling the release of the drug from the soft microrobot.
['Lee|Hyoryong|H|', 'Choi|Hyunchul|H|', 'Lee|Mikyoung|M|', 'Park|Sukho|S|0000-0002-8699-897X']
D000178:Acrylamides D000464:Alginates D045744:Cell Line, Tumor D002470:Cell Survival D004317:Doxorubicin D016503:Drug Delivery Systems D065546:Drug Liberation D055590:Electromagnetic Phenomena D006801:Humans D020100:Hydrogels D007259:Infrared Rays D055616:Microtechnology D012371:Robotics
Electromagnetic actuation Near-infrared stimulus Temperature responsive Magnetic nanoparticles Controlled drug releasing Hydrogel-based microrobot