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Kai Dong,* Zhuang-Zhuang Zhao,* Jian Kang, Lei-Ruo Lin, Wen-Ting Chen, Jin-Xi Liu, Xiang-Long Wu, Ting-Li Lu Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi’an, Shaanxi, People’s Republic of China*These authors contributed equally to this workCorrespondence: Ting-Li LuKey Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi’an, Shaanxi, People’s Republic of ChinaTel/Fax +86-29-88460332Email lutinglixinxin@nwpu.edu.cnBackground: Combined chemotherapy is often affected by the different physicochemical properties of chemotherapeutic drugs, which should be improved by the reasonable design of co-loaded preparations.Purpose: A kind of simple but practical graphene oxide (GO) wrapped mesoporous silica nanoparticles (MSN) modified with hyaluronic acid (MSN@GO-HA) were developed for the co-delivery of cinnamaldehyde (CA) and doxorubicin (DOX), in order to enhance their combined treatment on tumor cells and reduce their application defects.Methods: The MSNCA@GODOX-HA was constructed by MSNCA (loading CA via physical diffusion) and GODOX-HA (modified with HA and loading DOX via π–π stacking) through the electrostatic adsorption, followed by the physicochemical characterization, serum stability and in vitro release study. Cytotoxicity on different cells was detected, followed by the tumor cell uptake tests. The intracellular reactive oxygen species (ROS) changes, mitochondrial functions and activities of caspase-3/-9 in MCF-7 cells were also evaluated, respectively.Results: The MSNCA@GODOX-HA nanoparticles kept stable in FBS solution and achieved pH-responsive release behavior, which was beneficial to increase the accumulation of CA and DOX in tumor cells to enhance the treatment. MSNCA@GODOX-HA exerted higher cytotoxicity to MCF-7 human breast cancer cells than H9c2 cardiac myocyte cells, which were not only attributed to the active targeting to tumor cells by HA, but also related with the activation of intrinsic apoptotic pathway in MCF-7 cells induced by CA, which was mediated by the specific ROS signal amplification and the interference with mitochondrial function. Moreover, the efficacy of DOX was also enhanced by the above process.Conclusion: The establishment of the MSNCA@GODOX-HA nanoparticles played a role in promoting strengths and restricting shortcomings of CA and DOX, thereby exerting their function and achieving efficient treatment against cancer.Keywords: mesoporous silica nanoparticle, graphene oxide, hyaluronic acid, cinnamaldehyde, doxorubicin

Vertical cavity surface emitting lasers (VCSELs) have lots of excellent properties, such as circular beam, low threshold, single longitudinal mode, high speed modulation and monolithic array fabrication capability. The VCSELs have been widely used in data communication and short-distance optical interconnection. In the fields of distance detection and automatic driving, high accuracy lidars have become an indispensable component. In practical applications, 905 nm laser exhibits little absorption by the water vapor in the air. In addition, the 905 nm laser can match with both inexpensive Si detector and high response avalanche photodiode (APD). Therefore, the 905 nm semiconductor laser has become a key light source of lidar. This paper presents the design and fabrication of 905 nm VCSEL with high power conversion efficiency. First, the main factors influencing the power conversion efficiency (PCE) of VCSEL are analyzed theoretically. It is concluded that the slope efficiency contributes to the PCE most. In order to achieve a high slope efficiency, strained InGaAs is used as a quantum well material. Due to the wavelength redshift caused by the thermal effect, the lasing peak wavelength of the multiple quantum well (MQW) is designed to be about 892 nm by optimizing the In composition. The active region consists of three pairs of In0.123Ga0.88As/Al0.3Ga0.7 MQWs. The N-distributed Bragg reflectors (DBRs) are designed to have 40 pairs of Al0.9Ga0.1As/Al0.12Ga0.88As, and the P-DBRs are designed to have 20 pairs of Al0.9Ga0.1As/Al0.12Ga0.88As. The epitaxial structure is designed and grown by metal organic chemical vapor deposition (MOCVD). The cavity mode of the epitaxial wafer is around 903.7 nm. The photoluminescence (PL) spectrum is also measured. The peak wavelength is approximately 893.7 nm, and the full width at half maximum is 21.6 nm. Then, the 905 nm VCSELs with different apertures (6–18 μm) are fabricated via semiconductor technologies such as photolithography, evaporation, inductively coupled plasma (ICP), wet oxidation, electroplating, etc. Finally, the L-I-V characteristics and spectra of VCSELs with different apertures are tested. The obtained maximum slope efficiency and PCE of the devices are 1.12 W/A and 44.8%, respectively. In addition, the influences of aperture size on the far-field profiles and spectra of the devices are investigated. These 905 nm VCSELs with high PCE are potential for the miniaturization and lowing the cost of LiDAR.