Catheters, polymer‑based devices inserted into human blood vessels, require surface coatings to prevent vascular wall damage and to provide antimicrobial and antithrombotic functions. Currently, hydrophilic (hydrophilic) coatings are used to provide low friction, and multifunctionality is achieved by adding antibiotics, silver ions, or heparin to the coating layers to confer antimicrobial and antithrombotic properties. However, these additives can leach from the coating layers, causing antimicrobial and antithrombotic efficacy to gradually decline and limiting long‑term performance; antibiotics furthermore raise concerns about resistance.

A joint research team composed of Professor Seung‑Hwa Yoo of the Department of Quantum System Engineering at Jeonbuk National University (JBNU), Senior Researcher Dong‑Yun Choi of the Biomedical Manufacturing Technology Center at the Korea Institute of Industrial Technology, and Professor Dong‑Yun Lee of the Department of Polymer Engineering at Kyungpook National University has developed a new coating technology that can overcome these limitations.

The research team announced on the 7th that they developed a vascular catheter coating technology that forms the coating layer from a single material—a biodegradable natural polymer chitosan derivative—using an aqueous‑based manufacturing process, producing a high‑performance, multifunctional (antimicrobial, antithrombotic, low‑friction) surface.

The results of this study were published online on January 7, 2022 in Chemical Engineering Journal (IF=13.273), an international journal in the field of chemical engineering ranked in the top 2.45% by Journal Citation Reports (JCR).

Existing catheter coating technologies not only face performance degradation, but also use toxic, volatile organic solvent‑based coating solutions to strongly bind coating layers to the low‑surface‑energy polymer surfaces of medical devices. This exposes workers to health risks during the coating process and creates potential safety concerns for catheter patients due to residual solvents in the coating layers.

To overcome these hazards and effectively treat low‑surface‑energy polymer surfaces, the research team introduced hydrophilicity using an aqueous‑based electron‑beam graft polymerization method. They then produced the coating layer by dip‑coating an aqueous solution of a chitosan derivative onto the hydrophilically treated polymer surface.

In addition, to maximize the coating layer's functionality, they created a superhydrophilic surface by simply controlling the coating layer's porosity. The anti‑adhesion effect of the superhydrophilic surface combined synergistically with the intrinsic multifunctionality of the chitosan derivative, producing a coating layer from a single material that exhibits high antimicrobial, antithrombotic, and low‑friction properties.

In practice, the research team applied the developed coating method to a medical catheter (1 m in length) and conducted tests using an artificial mock blood vessel. The tests verified excellent trackability, demonstrating the potential for application to catheters currently used in procedures and raising expectations for near‑term commercialization.

Notably, because the electron‑beam graft polymerization method can, in theory, treat all types of polymer surfaces, combining it with dip‑coating is expected to enable application not only to catheters but also to a range of medical devices such as vascular filters, vascular grafts, pacemakers, and soft robots. Moreover, since the entire process is eco‑friendly and non‑hazardous, it should be applicable to various devices intended for human use.

Professor Seung‑Hwa Yoo said, "I am pleased that research which began as an effort to address the challenges of current technologies using radiation technologies has concluded with positive results," and added, "We plan to continue steady research on the production and application of new materials using various radiation technologies."