KAIST team unveils gravity-independent wearable eyedrop patch for space

On October 21, KAIST said its team built a wearable patch that puts eyedrops into the eye without using gravity.

The study was led by Professor Ki-Hun Jeong of the KAIST Department of Bio and Brain Engineering and Professor Se Joon Woo of Seoul National University Bundang Hospital. Jaehun Jeon, a doctoral student in the KAIST Department of Bio and Brain Engineering, served as the study’s first author. The paper by Jaehun Jeon and colleagues came out online on October 7. The results appeared in the international journal Sensors and Actuators B: Chemical under the title “Wearable self-instillation microfluidic eyedrop patch for space medicine,” with the DOI 10.1016/j.snb.2026.140885.

The KAIST announcement issued on October 21 names President Choongsik Bae and describes the work as addressing the difficulty of applying medication in near-zero gravity. Phys.org and alphagalileo.org say applying eyedrops is difficult in space because there is almost no gravity. They frame the work as space medicine for crews on long-duration exploration missions.

The research responds to a constraint in space medicine. Astronauts flying long-duration exploration missions need technology that lets them manage their health without direct help from medical staff. Microgravity shifts body fluids toward the head, and that shift can change the structure of the eyes and affect visual function. Because the standard Earth method of applying eyedrops depends on liquid falling by gravity, astronauts cannot use it in space without modification.

The new device is a single flexible patch that combines liquid-carrying microchannels with a pressure-generating chemical reaction chamber. Microchannels are narrow fluid pathways built into the patch. It adheres to the skin surrounding the eye, giving the wearer a stable base for exact delivery of medication. The compact, lightweight build limits interference with everyday activities during orbit and makes the patch versatile and convenient for space missions while supporting astronaut eye health without disrupting daily routines.

Operation does not require an external pump or electrical drive. When the user presses the actuation area, ascorbic acid (vitamin C) and sodium bicarbonate, the main component of baking soda, contact water and produce carbon dioxide gas. That gas pressure pushes the eyedrop through the microchannel to the eye, replacing the role that gravity normally plays. The chemical reaction chamber and the pressure generation are internal to the device, so it works without drawing on cabin power or equipment.

A filter placed between the reaction chamber and the eyedrop chamber allows gas to pass while blocking liquid, keeping the reactants separate from the medication even as the filter transmits pressure. The microfluidic channel system supports customized dosing schedules and individualized treatment plans based on each person’s needs. Intricate channels enable precise control of fluid dynamics, so the medication reaches the eye consistently. The design suggests possible uses in terrestrial clinical settings as well as in space.

Life Technology describes the patch as a platform for controlled delivery in space, suited to missions where normal medication administration is impractical. Its microfluidic channels manage fluid flow without gravity.

Researchers conducted tests on Earth. In Earth-based tests, the patch kept releasing drops at the same rate whatever direction gravity faced. When tested on human bodies, the patch put the drug into the eye about as well as the usual way of applying drops.

Because those results came from Earth-based experiments, use in an actual space environment still requires further verification. Phys.org and alphagalileo.org present this caveat after the positive tests, before noting possible Earth uses for people with tremors or physical limitations.

The technology may also help people on Earth who struggle to aim an eyedrop container because of hand tremors or physical limitations, including patients with Parkinson’s disease. The study presents personal drug delivery technology that lets people apply eyedrops by themselves in space. This capability supports astronaut health management without direct medical-staff help during long missions.

Professor Ki-Hun Jeong described the patch as a wearable platform that delivers medication without complex equipment. He said he expects the technology to expand to space medicine and other settings. “The flexible eyedrop patch developed in this study is a wearable platform that can deliver medication without complex additional equipment,” Jeong said.

Three South Korean government programs supported the research. The Korean ARPA-H Project, administered through the Korea Health Industry Development Institute and the Ministry of Health & Welfare, provided funding under RS-2024-00512384. The National Research Foundation of Korea, through the Ministry of Science and ICT, supported the work under RS-2025-00523089. The Technology Innovation Program, through the Ministry of Trade, Industry and Resource, contributed under RS-2024-00432381.

The funding disclosure appears at the end of the KAIST announcement beside the paper citation. It appears alongside regions tags and a keyword list for the release.

Phys.org and alphagalileo.org describe the operating environment as one with almost no gravity, where applying eyedrops is difficult. They frame the work as space medicine intended for crews on long-duration exploration missions.