Micromotor Based Mini-Tablet for Oral Delivery of Insulin

Abstract

Diabetes is a metabolic disorder characterized by hyperglycemia due to defective insulin secretion or its biological dysfunction. However, frequent subcutaneous injection of insulin often results in discomfort and local tissue infection. Herein, we demonstrate the successful fabrication of a mini-tablet system based on self-propelled micromotors with biocompatibility and biodegradability for oral colon administration of insulin. The insulin layer is first constructed onto the surface of a magnesium based micromotor via electrostatic interactions, followed by a tableting process. The resulting mini-tablets are then coated with esterified starch with colonic degradation capability, thus achieving controlled release of the embedded micromotors in the colon region. In the meantime, autonomous movement of the released micromotors with a speed up to 76.22 μm·s–1 further results in enhanced colonic uptake and absorption of insulin, realizing long-term control of blood glucose for more than 5 h. Our micromotor based mini-tablet system can not only broaden the biomedical applications of emerging self-propelled micromotors but also offer an appealing strategy for oral administration of biomacromolecular drugs represented by insulin.

In vivoapplications of micro/nanorobots

“…25,31,32 Due to these reactions, Mgand Zn-based microrobots can produce hydrogen (H 2 ) bubbles, leading to propulsion in the stomach and/or intestine. [33][34][35][36][37] An asymmetric platinum coating or deposition can also provide bubble-propelled motion upon contact with fuel, i.e., hydrogen peroxide (H 2 O 2 ). 38,39 Although it is a convenient approach to obtain self-propelled micro/nanorobots, the toxicity of H 2 O 2 constrains practical biomedical applications.…”

“…25,31,32 Due to these reactions, Mg- and Zn-based microrobots can produce hydrogen (H 2 ) bubbles, leading to propulsion in the stomach and/or intestine. 33–37 An asymmetric platinum coating or deposition can also provide bubble-propelled motion upon contact with fuel, i.e. , hydrogen peroxide (H 2 O 2 ).…”

A drug co-delivery platform made of magnesium-based micromotors enhances combination therapy for hepatoma carcinoma cells

“…[25][26][27][28] Recently, magnesium (Mg)-based micromotors have been synthesized to deliver drugs in vivo as they can react with biofluids to produce hydrogen for propulsion. [29][30][31] Being a necessary trace element for human body, Mg is biocompatible, and its degradation product in the physiological environment is harmless to tissues and cells. 30,32 To date, diverse micromotors have demonstrated the possibility of co-drug delivery.…”

Nanorobot-Mediated Synchronized Neuron Activation

“…Synthetic micro/nanomotors, or miniaturized autonomous robots, can convert external chemical, , light, , magnet, , heat, and ultrasound energy into local gradients, thus resulting in motion capability. Recent studies suggest the possibility of collective behaviors of micro/nanomotors. − Herein, we propose programmed swarming of oscillating nanorobots with the field information behind propulsion and swarming as a medium to communicate with biological neurons in vitro and trigger neural oscillation.…”

“…Synthetic micro/nanomotors, or miniaturized autonomous robots, can convert external chemical, 22,23 light, 24,25 magnet, 26,27 heat, 28 and ultrasound 29 energy into local gradients, thus resulting in motion capability. Recent studies suggest the possibility of collective behaviors of micro/nanomotors.…”