Upconversion 3D Printed Composite with Multifunctional Applications for Tissue Engineering and Photodynamic Therapy

Abstract

Upconversion nanoparticles (UCNPs) are suitable materials for bioapplications due to their ability to emit visible light under near infrared (NIR) excitation, in the biological transparency range. Polycaprolactone(PCL)-based scaffolds are widely used in tissue engineering in combination with inorganic compounds to improve bioactivity and osteoconductive properties. This work proposes a 3D printed composite scaffold with upconversion property aiming at biomedical applications in therapy-stimulated bone repair and photodynamic therapy (PDT). The system combines PCL polymer, UCNPs-apatite and a PDT photosensitizer. Thermal and rheological behaviors of the composite were similar to pure PCL polymer. Mechanical properties were improved by adding UCNPs-apatite. The 3D printable composite presented upconversion property and potential for PDT application, which was demonstrated by singlet oxygen generation under 980 nm excitation. Cytotoxicity, genotoxicity and mutagenicity assays indicated no toxicological effects at low concentrations of rare earth elements. Taken together, a potential multifunctional material is proposed for biomedical applications.

Upconversion Luminescent Nanoparticles and Their Biomedical Applications in Imaging

“…Nigoghossian et al [121] focused on evaluating the cytotoxicity, genotoxicity, and mutagenicity of UCNPs incorporated into a 3D-printed composite scaffold with upconversion luminescence for potential biomedical applications. Their system combined the polymer PCL, UCNPs-apatite, and a photosensitizer for PDT in stimulating bone repair.…”

Functional anti-bone tumor biomaterial scaffold: construction and application

“…PS-PCL/UCNPs-apatite composite produced singlet oxygen and displayed PDT properties while the 3D printed scaffold had no effect on optical properties. 50 However, PCL/UCNPs-apatite is genotoxic and mutagenic toward CHO-K1 cells at higher concentrations of rare earth elements and can currently only be used at lower biosafe concentrations.…”

Nanomaterial integrated 3D printing for biomedical applications

“…Nigoghossian et al developed UCNP-based scaffolds for photodynamic therapy (PDT) under 980 nm excitation. 140 Here, UCNPs were used as a transducer to initiate a photosensitizer (erythrosine B) in polymerization. When 12.5 wt% UCNPs and erythrosine B are embedded into polymeric materials using FDM technology, a proof-of-concept study confirmed that fabricated scaffolds could generate cytotoxic singlet oxygen under NIR excitation, inducing cell apoptosis.…”