Benidipine-loaded nanoflower-likemagnesium silicate improves bone regeneration

Regeneration and reconstruction of bone tissue is always a challenge for clinicians due to the uncertainty of bone repair materials in terms of long-term and efficient effects on osteoblasts.Here,we propose a novel strategy combining benidipine,an antihypertensive drug and nanoparticles to synergistically promote the healing of bone defects.Loose and porous benidipine-loaded magnesium silicate nanoparticles were prepared and validated for their biosafety.The nanoparticles were efficiently taken up by preosteoblasts and uniformly distributed around the nucleus.After internalization into cells,the nanosystem is degraded by lysosomes,and the effect of promoting osteogenic differentiation is reflected by the continuous release of benidipine,silicon and magnesium ions.Our results clearly evaluated that the nanoflower-like magnesium silicate delivering benidipine tends to be more appropriate for the bone regeneration in preosteoblasts,indicating that it might be a potential approach in guiding bone repair in clinical applications.

First-principles study on improvement of two-dimensional hole gas concentration and confinement in AlN/GaN superlattices

Using first-principles calculations based on density functional theory,we have systematically studied the influence of in-plane lattice constant and thickness of slabs on the concentration and distribution of two-dimensional hole gas(2 DHG)in AlN/GaN superlattices.We show that the increase of in-plane lattice constant would increase the concentration of 2 DHG at interfaces and decrease the valence band offset,which may lead to a leak of current.Increasing the thickness of AlN and/or decreasing the thickness of GaN would remarkably strengthen the internal field in GaN layer,resulting in better confinement of 2 DHG at AlN/GaN interfaces.Therefore,a moderate larger in-plane lattice constant and thicker AlN layer could improve the concentration and confinement of 2 DHG at AlN/GaN interfaces.Our study could serve as a guide to control the properties of 2 DHG at Ⅲ-nitride interfaces and help to optimize the performance of p-type nitride-based devices.

Rapid room-temperature synthesis of a porphyrinic MOF for encapsulating metal nanoparticles

While metal nanoparticles(NPs)have shown great promising applications as heterogeneous catalysts,their agglomeration caused by thermodynamic instability is detrimental to the catalytic performance.To tackle this hurdle,we successfully prepared a functional and stable porphyrinic metal-organic framework(MOF),PCN-224-RT,as a host for encapsulating metal nanoparticles by direct stirring at room temperature.As a result,Pt@PCN-224-RT composites with well-dispersed Pt NPs can be constructed by introducing pre-synthesized Pt NPs into the precursor solution of PCN-224-RT.Of note,the rapid and simple stirring method in this work is more in line with the requirements of environmental friendly and industrialization compared with traditional solvothermal methods.