Xiuli Ren

Preparation of Nickel Cobalt Sulfide Hollow Nanocolloids with Enhanced Electrochemical Property for Supercapacitors Application

Nanostructured functional materials with hollow interiors are considered to be good candidates for a variety of advanced applications. However, synthesis of uniform hollow nanocolloids with porous texture via wet chemistry method is still challenging. In this work, nickel cobalt precursors (NCP) in sub-micron sized spheres have been synthesized by a facile solvothermal method. The subsequent sulfurization process in hydrothermal system has changed the NCP to nickel cobalt sulfide (NCS) with porous texture. Importantly, the hollow interiors can be tuned through the sulfurization process by employing different dosage of sulfur source. The derived NCS products have been fabricated into supercapacitor electrodes and their electrochemical performances are measured and compared, where promising results were found for the next-generation high-performance electrochemical capacitors.

In situ mineralization of anticancer drug into calcium carbonate monodisperse nanospheres and their pH-responsive release property

In this paper, we facilitated the preparation of uniform calcium carbonate nanospheres and the encapsulation of anticancer drug (Doxorubicin, Dox) in one step by a facile bio-inspired mineralization method at room temperature. Hesperidin (Hesp), a natural originated flavanone glycoside, was introduced as crystallization modifier. The obtained Dox encapsulated CaCO3 nanospheres (Dox@CaCO3-Hesp NSs) having a narrow size range of ~200 nm. The drug loading/release studies reveal that these Dox@CaCO3-Hesp NSs have a drug loading efficiency (DLE) of 83% and drug loading content (DLC) of 14wt%. Besides, the release of Dox from Dox@CaCO3-Hesp NSs was pH depended. At pH=7.4, only a small amount (~28%) of Dox was released. While at pH=5.0, all amount of incorporated Dox was released. Confocal laser scanning microscopy (CLSM) image reveals the Dox@CaCO3-Hesp NSs can internalize the cells. These results suggest the Dox@CaCO3-Hesp NSs can be potentially used to utilize pH-responsive delivery of anticancer drugs.

Preparation of core–shell structured CaCO 3 microspheres as rapid and recyclable adsorbent for anionic dyes

Core–shell structured CaCO3 microspheres (MSs) were prepared by a facile, one-pot method at room temperature. The adsorbent dosage and adsorption time of the obtained CaCO3 MSs were investigated. The results suggest that these CaCO3 MSs can rapidly and efficiently remove 99–100% of anionic dyes within the first 2 min. The obtained CaCO3 MSs have a high Brunauer–Emmett–Teller surface area (211.77 m2 g−1). In addition, the maximum adsorption capacity of the obtained CaCO3 MSs towards Congo red was 99.6 mg g−1. We also found that the core–shell structured CaCO3 MSs have a high recycling capability for removing dyes from water. Our results demonstrate that the prepared core–shell structured CaCO3 MSs can be used as an ideal, rapid, efficient and recyclable adsorbent to remove dyes from aqueous solution.

Preparation of anticancer micro-medicine based on quinoline and chitosan with pH responsive release performance

N-(2-(3-fluorobenzyl)-2H-indazol-5-yl)-2-phenyl-2H-pyrazolo[4,3-c]qui- nolin-4-amine (LZC-2b) with a quinoline structure was synthesized as an anticancer prodrug. The pH sensitive anticancer drugs obtained by a simple hydrothermal method. The interaction of chitosan (Cts) and LZC-2b is used to complete the encapsulation without any cross-linking. The obtained micromedicine (LZC-2b@Cts-MSs) has an average size of ∼980 nm. The drug loading efficiency (DLE) of LZC-2b@Cts-MSs was about 79%. In addition, drug release from LZC-2b@Cts-MSs was pH depended. At pH = 7.4, only 5.1% of loaded LZC-2b was released, while 90.3% of loaded LZC-2b was released at pH = 5.0. Cell culture results indicate that LZC-2b@Cts-MSs can be easily uptaken by KB cells. Cell viability results show that KB cells can be effectively killed by LZC-2b@Cts-MSs. Our strategy of synthesis and preparation of pH responsive LZC-2b@Cts-MSs has promising prospect in chemotherapy of oral cancer.

GSH and enzyme responsive nanospheres based on self-assembly of green tea polyphenols and BSA used for target cancer chemotherapy

Developing safe and effective stimuli-responsive nanocarriers is very important for tumor chemotherapy. In this work, bovine serum albumin (BSA) and green tea polyphenol (TP) were used to prepare glutathione (GSH) and enzyme (trypsin) responsive nanocarriers for doxorubicin (DOX). These nanocarriers were further modified with folate, briefly named as DOX@BSA-TP-FA NSs. The diameter of nanocarriers was about 220 nm. The DOX loading efficiency and loading amount were 86.4% and 23.5 wt%, respectively. The cellular uptake, apoptosis, and GSH and trypsin responsive release properties of these nanocarriers were investigated.

Fast ion transport through ultrathin shells of metal sulfide hollow nanocolloids used for high-performance energy storage

Metal sulfide (MS, nickel sulfide/copper sulfide) hollow spheres with hierarchical, ultrathin shell structures have been constructed by a facile method. The as-formed MS hollow structures are shown to be uniform in sizes with hierarchical ultrathin shells, which could facilitate the transport of electrolyte ions. Electrochemical evaluations of the as-fabricated MS based materials as supercapacitors electrodes having high large surface area (106–124 m2 g−1) and high specific capacitances (up to 1460 F g−1) with good cycling stability (up to 94% retention after 5000 cycles), showing their potential applications in the next-generation high-performance supercapacitors used for energy storage.

Promoting proliferation and differentiation of BMSCs by green tea polyphenols functionalized porous calcium phosphate

Abstract In this article, we proposed a facile protocol to functionalize porous calcium phosphate ceramics (PCPC) using dietary tea polyphenols (TP). TP molecules was attracted and anchored by Ca2+ ions from the surface of CPC. These TP molecules modulated the nucleation and crystallization of calcium phosphate nanorods assemblies on the surface of PCPC. Our results prove that these calcium phosphate nanorods assemblies accompanies functional groups of TP make PCPC/TP effectively promote proliferation and differentiation of bone mesenchymal stem cells (BMSCs). We inferred that these calcium phosphate nanorods assemblies might change the surface microenvironment of PCPC, which is critical to promote the proliferation and differentiation of BMSCs. Compared with naked PCPC, PCPC/TP obviously increased BMP2, ErK/MAPK and JNK/MAPK level and mineralization capacity of cells (ALP level).

Protein-mediated mineralization of edaravone into injectable, pH-sensitive microspheres used for potential minimally invasive treatment of osteomyelitis

Osteomyelitis, an infection within bone, is difficult to treat. Conventional surgical treatment causes severe pain in the patients physically and mentally. There is an urgent need to develop injectable nano- and/or micro-medicine for minimally invasive treatment of osteomyelitis. In this study, we provide a facile protocol of protein-mediated mineralization of edaravone into injectable, pH-sensitive CaCO3 microspheres used for potential minimally invasive treatment of osteomyelitis. The mineral part of the composite microspheres is used to neutralize the acidic environment caused by bacterial infection. At the same time, edaravone encapsulated in CaCO3 microspheres is released to resist oxidative stress. The drug loading efficiency (DLE) and the drug loading content (DLC) are 89.4% and 19.2%, respectively. Our results demonstrate that the prepared microspheres can protect and promote the proliferation and differentiation of osteoblasts under stimulation of H2O2 at lower pH.

Construction of injectable, pH sensitive, antibacterial, mineralized amino acid yolk-shell microspheres for potential minimally invasive treatment of bone infection

Introduction Treatment of infection within bone is difficult, and conventional surgical treatment brings intense pain to the patients physically and mentally. There is an urgent need to develop injectable nano- and/or micro-medicine for minimally invasive treatment of osteomyelitis. Methods In this paper, amino acid (L-lysine [Lys]) was mineralized into yolk-shell structured CaCO3 microspheres (MSs). The morphologies of the obtained MSs were investigated by scanning electron microscopy and transmission electron microscopy. The composition of CaCO3 MSs was identified by using Fourier transform infrared spectroscopy. The as-prepared CaCO3 MSs were examined with power X-ray diffraction analysis to obtain the crystallographic structure of the MSs. Results The as prepared Lys encapsulated CaCO3 MSs (Lys@CaCO3 MSs) were used as micro-drug to improve acidic environment of osteomyelitis caused by bacterial infection and promote osteoblast proliferation under oxidative stress. These pH responsive Lys@CaCO3 MSs have a drug loading efficiency of 89.8 wt % and drug loading content (DLC) of 22.3 wt %. Conclusion Our results demonstrated that Lys@CaCO3 MSs can effectively kill Staphylococcus aureus and promote proliferation and differentiation of osteoblasts under stimulation of H2O2 at pH = 5.5.

Encapsulation of green tea polyphenol by pH responsive, antibacterial, alginate microgels used for minimally invasive treatment of bone infection

The treatment of bone infection requires drug carriers take large number of cargo, be antibacterial, promote proliferation and differentiation of osteoblasts. Herein, we proposed a strategy of preparing pH responsive, antibacterial, multistage structured microspheres encapsulated with green tea polyphenol used for minimally invasive treatment of bone infection. Tea polyphenol (TP) were encapsulated by porous silica nanospheres (SiO2 NSs). Then, sodium alginate (SA) microgel spheres (MSs) were prepared to encapsulate a lot of TP loaded SiO2 NSs. The outer layer of obtained TP@SiO2@SA microgel spheres were further wrapped by pH sensitive CaCO3. Mineral out-layer of the composite microspheres is used to neutralize the acidic environment caused by bacterial infection. At the same time, encapsulated TP is released pH sensitively to resist oxidative stress. Our results exhibited excellent drug delivery properties including drug loading efficiency (DLE) of 92.96% and drug loading content (DLC) of 19.62%. Besides, results demonstrated that TP@SiO2@SA@CaCO3 MSs can effectively kill Staphylococcus aureus and promote proliferation and differentiation of osteoblasts under stimulation of H2O2 at pH = 5.5.