A Comparative Study on Sorption Characteristics by Corn Stalk Pith Using Green Modification with Different Polycarboxylic Acids

Tingyu Fan,Shuping Cheng,Dan Peng,Sifang Kong 한국섬유공학회 2021 Fibers and polymers Vol.22 No.3

In this study, an efficient and economical modification with low chemical concentration process was used forpreparing biosorbent. Corn stalk pith (CP) was esterified with different polycarboxylic (tartaric, citric, and malic) acids, andthen the resultant modified products were applied as sorbents to remove methylene blue (MB) via sorption. Compared withthe raw materials, the esterification led to some variation in the specific surface area, pore volume and structure, whichthereby affected the sorption efficacy of MB. The pseudo-second-order kinetic model and the Langmuir model welldescribed the MB sorption for all modified CPs. Following modification, sorption capacity increased by 290.1 % for tartaricacid modified-CP, 759.0 % for citric acid modified-CP and 658.2 % for malic acid modified-CP, and the maximum MBsorption were 208.3, 458.7 and 404.9 mg/g, respectively. The mechanisms of MB sorption via modified CP involveelectrostatic interaction, π-π interaction, and hydrogen bonds interaction. The substantial enhancement on MB sorption by theCP esterified with polycarboxylic acids provides a novel means for dyes removal from wastewater.

Transcrystalline growth of PLLA on carbon fiber grafted with nano-SiO2 towards boosting interfacial bonding in bone scaffold

Pei Feng,Jiye Jia,Shuping Peng,Yang Shuai,Hao Pan,Xinna Bai,CIJUN SHUAI 한국생체재료학회 2022 생체재료학회지 Vol.26 No.1

Background: The reinforcement effect of fiber-reinforced polymer composites is usually limited because of the poor interfacial interaction between fiber and polymer, though fiber reinforcement is regarded as an effective method to enhance the mechanical properties of polymer. Methods: In this study, nano-SiO2 particles grafted by 3-Glycidoxypropyltrimethoxysilane (KH560) were introduced onto the surface of 3-Aminopropyltriethoxysilane (KH550) modified carbon fiber (CF) by a self-assembly strategy to improve the interfacial bonding between CF and biopolymer poly (lactic acid) (PLLA). Results: The results indicated that PLLA chains preferred to anchor at the surface of nano-SiO2 particles and then formed high order crystalline structures. Subsequently, PLLA spherulites could epitaxially grow on the surface of functionalized CF, forming a transcrystalline structure at the CF/PLLA interface. Meanwhile, the nano-SiO2 particles were fixed in the transcrystalline structure, which induced a stronger mechanical locking effect between CF and PLLA matrix. The results of tensile experiments indicated that the PLLA/CF-SiO2 scaffold with a ratio of CF to SiO2 of 9:3 possessed the optimal strength and modulus of 10.11 MPa and 1.18 GPa, respectively. In addition, in vitro tests including cell adhesion and fluorescence indicated that the scaffold had no toxicity and could provide a suitable microenvironment for the growth and proliferation of cell. Conclusion: In short, the PLLA/CF-SiO2 scaffold with good mechanical properties and cytocompatibility had great potential in the application of bone tissue engineering.

Processing and Characterization of Laser Sintered Hydroxyapatite Scaffold for Tissue Engineering

CIJUN SHUAI,Pei Feng,Chengde Cao,SHUPING PENG 한국생물공학회 2013 Biotechnology and Bioprocess Engineering Vol.18 No.3

The sintering processing of hydroxyapatite (HAP) powder was studied using selective laser sintering for bone tissue engineering. The effect of laser energy density on the microstructure, phase composition and mechanical properties of the sintered samples was investigated. The results indicate that the average grain size increases from 0.211 ± 0.039 to 0.979 ± 0.133 μm with increasing the laser energy density from 2.0 to 5.0 J/mm2. The maximum value of Vickers hardness and fracture toughness were 4.0± 0.13 Gpa and 1.28 ± 0.033 MPam1/2, respectively, when the laser energy density was 4.0 J/mm2. The XRD results indicated that the nano-HAP was decomposed into TCP with the laser energy density of above 4.0 J/mm2. In vitro bioactivity after soaking in simulated body fluid (SBF) for 3 ~ 12 days showed that a bone-like apatite layer on the surface of the sintered samples. It indicated that the HAP scaffold possesses favorable mechanical properties and bioactivity, and may be used for bone tissue engineering.

miR-30c regulates proliferation, apoptosis and differentiation via the Shh signaling pathway in P19 cells

Xuehua Liu,Mengmeng Li,Yuzhu Peng,Xiaoshan Hu,Jing Xu,Shasha Zhu,Zhangbin Yu,Shuping Han 생화학분자생물학회 2016 Experimental and molecular medicine Vol.48 No.-

MicroRNAs (miRNAs) are small, non-coding single-stranded RNAs that suppress protein expression by binding to the 3′ untranslated regions of their target genes. Many studies have shown that miRNAs have important roles in congenital heart diseases (CHDs) by regulating gene expression and signaling pathways. We previously found that miR-30c was highly expressed in the heart tissues of aborted embryos with ventricular septal defects. Therefore, this study aimed to explore the effects of miR-30c in CHDs. miR-30c was overexpressed or knocked down in P19 cells, a myocardial cell model that is widely used to study cardiogenesis. We found that miR-30c overexpression not only increased cell proliferation by promoting cell entry into S phase but also suppressed cell apoptosis. In addition, we found that miR-30c inhibited dimethyl sulfoxide-induced differentiation of P19 cells. miR-30c knockdown, in contrast, inhibited cell proliferation and increased apoptosis and differentiation. The Sonic hedgehog (Shh) signaling pathway is essential for normal embryonic development. Western blotting and luciferase assays revealed that Gli2, a transcriptional factor that has essential roles in the Shh signaling pathway, was a potential target gene of miR-30c. Ptch1, another important player in the Shh signaling pathway and a transcriptional target of Gli2, was downregulated by miR-30c overexpression and upregulated by miR-30c knockdown. Collectively, our study revealed that miR-30c suppressed P19 cell differentiation by inhibiting the Shh signaling pathway and altered the balance between cell proliferation and apoptosis, which may result in embryonic cardiac malfunctions.

FABRICATION OPTIMIZATION OF NANOHYDROXYAPATITE ARTIFICIAL BONE SCAFFOLDS

CIJUN SHUAI,CHENGDE GAO,YI NIE,PENGJIAN LI,JINGYU ZHUANG,SHUPING PENG,HUANLONG HU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2012 NANO Vol.7 No.3

Serious microcracks often occur on the surface of nanohydroxyapatite (n-HAP) artificial bone scaffolds prepared by selectivelaser sintering(SLS) technology. In this study, we found that appropriate preheating before sintering can reduce and attenuate the cracks. The experiments showed that the cracks gradually reduced and then disappeared when the preheating temperature increased from 0 to 600°C while other parameters remain unchanged. The n-HAP particles gradually fused and grew up, while the grain size of sintered n-HAP will be attenuated with the increase of preheating temperature. This provided experimental optimal condition for the preparation of artificial bone scaffolds with nanohydroxyapatite ceramics.

Construction of magnetic nanochains to achieve magnetic energy coupling in scaffold

Cijun Shuai,Xuan Chen,Chongxian He,Guowen Qian,Yang Shuai,SHUPING PENG,Youwen Deng,Wenjing Yang 한국생체재료학회 2022 생체재료학회지 Vol.26 No.3

Background: Fe3O4 nanoparticles are highly desired for constructing endogenous magnetic microenvironment in scaffold to accelerate bone regeneration due to their superior magnetism. However, their random arrangement easily leads to mutual consumption of magnetic poles, thereby weakening the magnetic stimulation effect. Methods: In this study, magnetic nanochains are synthesized by magnetic-field-guided interface co-assembly of Fe3O4 nanoparticles. In detail, multiple Fe3O4 nanoparticles are aligned along the direction of magnetic force lines and are connected in series to form nanochain structures under an external magnetic field. Subsequently, the nanochain structures are covered and fixed by depositing a thin layer of silica (SiO2), and consequently forming linear magnetic nanochains (Fe3O4@SiO2). The Fe3O4@SiO2 nanochains are then incorporated into poly l-lactic acid (PLLA) scaffold prepared by selective laser sintering technology. Results: The results show that the Fe3O4@SiO2 nanochains with unique core–shell structure are successfully constructed. Meanwhile, the orderly assembly of nanoparticles in the Fe3O4@SiO2 nanochains enable to form magnetic energy coupling and obtain a highly magnetic micro-field. The in vitro tests indicate that the PLLA/Fe3O4@SiO2 scaffolds exhibit superior capacity in enhancing cell activity, improving osteogenesis-related gene expressions, and inducing cell mineralization compared with PLLA and PLLA/Fe3O4 scaffolds. Conclusion: In short, the Fe3O4@SiO2 nanochains endow scaffolds with good magnetism and cytocompatibility, which have great potential in accelerating bone repair