Facile fabrication of water-soluble polyacrylic acid encapsulated core@shell upconversion nanoparticles via metal-free light induced surface initiated atom transfer radical polymerization

• Published in: Materials letters Vol. 273; p. 127874
• Main Authors: Chen, Ruyi, Zhang, Wenjie, Dai, Tianzhi, He, Jianhao, Ye, Haoming, Wang, Yudong
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15-08-2020; Elsevier BV
• Subjects: Acids; Acrylics; Encapsulation; Infrared lasers; Luminescence; Materials science; Medical imaging; Morphology; Nanocomposites; Nanoparticles; Optical materials and properties; Optical properties; Polyacrylic acid; Polymerization; Radicals; Upconversion; Water chemistry; Nanoparticles; Optical materials and properties; Nanocomposites; Luminescence
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2020.127874

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•The preparation of UCNP@PAA core@shell nanocomposites through LI-SI-ATRP.•The UCNP@PAA is hydrophilic and have upconversion luminescent properties.•An alternative way for the hydrophilic modification of other nanoparticles.•The UCNPs@PAA are promising candidates for luminescent bioimaging.
Upconversion nanoparticles (UCNP) have great potential for applications in biological fields due to their unique anti-stokes luminescent properties. However, the successful preparation of water-soluble upconversion nanoparticles with well-controlled morphology still remains a great challenge. Herein, a facile fabrication method for the preparation of water-soluble polyacrylic acid (PAA) encapsulated core@shell upconversion nanoparticles through metal-free light induced surface initiated atom transfer radical polymerization (LI-SI-ATRP) was presented. This method involves the modification of oleate acid capped upconversion nanoparticles by bi-functional ligands with ATRP initiating sites. Then the water-soluble polyacrylic acid modified core@shell upconversion nanoparticles were synthesized by metal-free light induced atom transfer radical polymerization. The nanoparticles prepared can be well dispersed in water and emit strong green light when excited by 980 nm near-infrared laser which suggesting that these PAA modified UCNP are promising candidates for luminescent bioimaging.