Near-infrared photopolymerization assisted by upconversion nanophosphors for biomedical applications

Alexander G Savelyev,Kirill V Khaydukov,Andrey V Nechaev,Polina A Demina,Vladimir A Semchishen,Alla N Generalova,Evgeny V Khaydukov,A.V Naumov,M.G Gladush,K.R Karimullin

doi:10.1051/epjconf/201819004018

Abstract

We present the concept and the experimental demonstration of near-infrared photopolymerization assisted by specially designed upconversion nanophosphors. The principle of this technique is based on conversion of 980 nm laser irradiation to ultraviolet photons subsequently absorbed by photoinitiator. The nonlinearity of upconversion allows for activation of the process locally in the laser beam waist. This approach enables precise fabrication of 3D constructs directly in the volume of photocurable composition. Furthermore, the presented technique is suitable for polymerization of a wide range of photocurable resins as well as gelation of hydrogels for biomedical applications.

Highlights

A broad range of techniques based on photo-induced polymerization have been developed
The polymerization of the exposed photocurable compositions (PCCs) is a linear process getting launched in every point within the irradiation penetration depth and depending only on exposure dose
We report on formation of structures in the volume of PCC using nearinfrared photopolymerization

Summary

Introduction

A broad range of techniques based on photo-induced polymerization have been developed. The overwhelming majority of those employs the single-photon absorption. The polymerization of the exposed photocurable compositions (PCCs) is a linear process getting launched in every point within the irradiation penetration depth and depending only on exposure dose. This approach is widely used in laser stereolithography [1] and direct light processing [2] when the photocurable resin is patterned and recoated layer by layer.

Results

Conclusion