Biphasic (Lu,Gd)_(3)Al_(5)O_(12)-based transparent nanoceramic color converters for high-power white LED/LD lighting

Ce doped Lu_(3)Al_(5)O_(12)(Ce:LuAG)transparent ceramics are considered as promising color converters for solid-state lighting because of their excellent luminous efficiency,high thermal quenching temperature,and good thermal stability.However,Ce:LuAG ceramics mainly emit green light.The shortage of red light as well as the expensive price of Lu compounds are hindering their application for white lighting.In this work,transparent(Lu,Gd)_(3)Al_(5)O_(12)–Al_(2)O_(3)(LuGAG–Al_(2)O_(3))nanoceramics with different replacing contents of Gd^(3+)(10%–50%)were successfully elaborated via a glass-crystallization method.The obtained ceramics with full nanoscale grains are composed of the main LuGAG crystalline phase and secondary Al_(2)O_(3) phase,exhibiting eminent transparency of 81.0%@780 nm.After doping by Ce^(3+),the Ce:LuGAG–Al_(2)O_(3) nanoceramics show a significant red shift(510 nm→550 nm)and make up for the deficiency of red light component in the emission spectrum.The Ce:LuAG–Al_(2)O_(3) nanoceramics with 20%Gd^(3+)show high internal quantum efficiency(81.5%in internal quantum efficiency(IQE),96.7%of Ce:LuAG–Al_(2)O_(3) nanoceramics)and good thermal stability(only 9%loss in IQE at 150℃).When combined with blue LED chips(10 W),0.3%Ce:LuGAG–Al_(2)O_(3) nanoceramics with 20%Gd^(3+)successfully realize the high-quality warm white LED lighting with a color coordinate of(0.3566,0.435),a color temperature of 4347 K,CRI of 67.7,and a luminous efficiency of 175.8 lm·W^(−1).When the transparent 0.3%Ce:LuGAG–Al_(2)O_(3) nanoceramics are excited by blue laser(5 W·mm^(−2)),the emission peak position redshifts from 517 to 570 nm,the emitted light exhibits a continuous change from green light to yellow light,and then to orange-yellow light,and the maximum luminous efficiency is up to 234.49 lm·W^(−1)(20%Gd^(3+)).Taking into account the high quantum efficiency,good thermal stability,and excellent and adjustable luminous properties,the transparent Ce:LuGAG–Al_(2)O_(3) nanoceramics with different Gd^(3+)substitution contents in this paper are believed to be promising candidates for high-power white LED/LD lighting.

Synergistic anti-tumor therapy by a homotypic cell membranecloaked biomimetic nanocarrier with exceptionally potent activity against hepatic carcinoma

Hepatic carcinoma(HC)is the sixth most frequently occurring malignancies and the third leading cause of cancer death worldwide.Sepantronium bromide(YM155)is a small molecule inhibitor of survivin,which has broad-spectrum anticancer therapeutic effects in various xenograft models.However,several-day continuous infusion is required to achieve greater antitumor efficacy because of rapid elimination from the blood circulation.Herein,a SMMC-7721 cancerous cyto-membrane-cloaked drug delivery system(DDS)(named as iM7721@GQD-YM),was developed for co-encapsulation of YM155 and graphene quantum dots(GQDs).Cytomembrane coating endowed iM7721@GQD-YM with effective targeting for homologous HC cells,excellent biocompatibility and favorable immunocompatibility for in vivo application.Surface decoration of iRGD peptide further enhanced its tumor targeting activity by iRGD-integrin recognition.In addition,under the irradiation of near-infrared ray(NIR),GQDs can directly kill tumors through photothermal effect and cause cell membrane rupture,accurately releasing YM155 at tumor sites.The physicochemical properties,in vivo and ex vivo anti-tumor efficacy,and mechanisms of iM7721@GQD-YM nanoparticles(NPs)were systematically investigated in this work.The experimental results clearly indicate that the versatile biomimetic DDS holds great potential for the treatment of HC,which merits further investigation in both pre-clinical and clinical studies.