Near-infrared light-activated nanosystem endows scaffold with controllable nitric oxide release for peripheral nerve regeneration.

The photosensitive S-nitrosocysteine (CysNO) could respond to light irradiation to produce nitric oxide (NO), exhibiting tremendous potential in accelerating peripheral nerve regeneration. However, its further application was limited by the burst release of NO and the requirement for ultraviolet excitation with low tissue penetration. Herein, a near-infrared-triggered NO controlled release nanosystem UCNP@ZIF-8/CysNO consisting of an upconversion nanoparticle (UCNP) core and zeolitic imidazolate framework-8 (ZIF-8) shell loading with CysNO was constructed, and then blended with poly-l-lactic acid powder to fabricate nerve scaffold by laser additive manufacturing technique.

Oxygen vacancy healing boosts the piezoelectricity of bone scaffolds.

Although barium titanate (BaTiO) presented tremendous potential in achieving self-powered stimulation to accelerate bone repair, pervasive oxygen vacancies restricted the full play of its piezoelectric performance. Herein, BaTiO-GO nanoparticles were synthesized by the growth of BaTiO on graphene oxide (GO), and subsequently introduced into poly-L-lactic acid (PLLA) powders to prepare PLLA/BaTiO-GO scaffolds by laser additive manufacturing. During the synthesis process, CO and C-OH in GO would respectively undergo cleavage and dehydrogenation at high temperature to form negatively charged oxygen groups, which were expected to occupy positively charged oxygen vacancies in BaTiO and thereby inhibit the formation of oxygen vacancies.

A CuS@g-CN heterojunction endows scaffold with synergetic antibacterial effect.

Graphitic carbon nitride (g-CN) had aroused tremendous attention in photodynamic antibacterial therapy due to its excellent energy band structure and appealing optical performance. Nevertheless, the superfast electron-hole recombination and dense biofilm formation abated its photodynamic antibacterial effect. To this end, a nanoheterojunction was synthesized via in-situ growing copper sulfide (CuS) on g-CN (CuS@g-CN).

Photoexcited wireless electrical stimulation elevates nerve cell growth.

Electrical stimulation was restrained by an external power supply and wires, despite its ability to promote nerve cell growth. Bismuth sulfide (BiS) offered a novel prospect for achieving wireless electrical stimulation due to its photoelectric effect. Herein, silver nanoparticles (Ag NPs) were in-situ grown on BiS surface (Ag/BiS) and then mixed with poly-L-lactic acid (PLLA) powders to fabricate PLLA-Ag/BiS conduits.

Constructing core-shell structured BaTiO@carbon boosts piezoelectric activity and cell response of polymer scaffolds.

Piezoelectric composites have shown great potential in constructing electrical microenvironment for bone healing since their integration of polymer flexibility and ceramic piezoelectric coefficient. Herein, core-shell structured BaTiO@carbon (BT@C) hybrid nanoparticles were prepared by in situ oxidative self-polymerization and template carbonization. Then the BT@C was introduced into polyvinylidene fluoride (PVDF) scaffolds manufactured by selective laser sintering.

Microstructure evolution and texture tailoring of reduced graphene oxide reinforced Zn scaffold.

Zinc (Zn) possesses desirable degradability and favorable biocompatibility, thus being recognized as a promising bone implant material. Nevertheless, the insufficient mechanical performance limits its further clinical application. In this study, reduced graphene oxide (RGO) was used as reinforcement in Zn scaffold fabricated via laser additive manufacturing.

Graphene-assisted barium titanate improves piezoelectric performance of biopolymer scaffold.

Biopolymer scaffold is expected to generate electrical stimulation, aiming to mimic an electrical microenvironment to promote cell growth. In this work, graphene and barium titanate (BT) was introduced into selective laser sintered poly-l-lactic acid (PLLA) scaffold. BT as one piezoelectric ceramic was used as the piezoelectric source, whereas graphene served as superior conductive filler.

Electrostatic self-assembly of FeO nanoparticles on graphene oxide: A co-dispersed nanosystem reinforces PLLA scaffolds.

Cell responses and mechanical properties are vital for scaffold in bone regeneration. FeO nanoparticles with excellent magnetism can provide magnetic stimulation for cell growth, while graphene oxide (GO) nanosheets are commonly used as reinforcement phases due to their high strength. However, FeO or GO is tended to agglomerate in matrix.

Surface modification enhances interfacial bonding in PLLA/MgO bone scaffold.

The poor interfacial bonding and resultant agglomeration of nanoparticles in polymer-based composite severely deteriorated their reinforcement effect. In this work, MgO nanoparticles (MgO-NPs) were surface modified with Poly (L-lactic acid-co-malic acid) (PLMA) to improve the interfacial compatibility in Poly-l-lactic acid (PLLA) scaffold manufactured by selective laser sintering. PLMA possess a hydrophilic end with carboxyl group (comes from the malic acid) and an l-lactic acid chain.

Functionalized BaTiO enhances piezoelectric effect towards cell response of bone scaffold.

Piezoelectric effect of polyvinylidene fluoride (PVDF) plays a crucial role in restoring the endogenous electrical microenvironment of bone tissue, whereas more β phase in PVDF leads to higher piezoelectric performance. Nanoparticles can induce the nucleation of the β phase. However, they are prone to aggregate in PVDF matrix, resulting in weakened nucleation ability of β phase.

Enhanced 3 μm luminescence properties based on effective energy transfer Yb : F→Dy : H in fluoaluminate glass modified by TeO.

Enhanced 3 μm luminescence of Dy based on the effective process of Yb:F2→Dy:H6 with a higher energy transfer coefficient of 7.36×10  cm/s in fluoaluminate glass modified by TeO was obtained. The energy transfer efficiency from Yb to Dy in Dy/Yb codoped glass was as high as 80%, indicating the effective energy transfer of Yb.