Zhihao Xu,Zhixiang Lv,Huijiao Yang,Jiashuo Zhang,Zijie Sun,Dawei He,Ruijiang Liu
A label-free electrochemical DNA detection strategy based on self-assembled α-Fe 2 O 3 /Fe 3 O 4 nanosheets with PNA-DNA hybridization process was developed for ultrasensitive detection of APOE ε4 gene, one of the most robust genetic risks for Alzheimer’s Disease (AD). In this work, magnetic α-Fe 2 O 3 /Fe 3 O 4 heterogeneous nanosheets were prepared by hydrothermal-calcined reduction method and loaded with Au nanoparticles (AuNPs) on their surfaces. The magnetic α-Fe 2 O 3 /Fe 3 O 4 @Au nanocomposites significantly enhanced the electrochemical response as a signal amplification matrix and were able to bind to the magnetic glassy carbon electrode (MGCE) surface by magnetic self-assembly. Moreover, owing to the high specificity and stable binding capacity of PNA with respect to the target DNA, the biosensor not only enabled accurate (the limit of detection was estimated to be 0.147 pM) and rapid detection of the APOE ε4 gene, but also exhibited excellent specificity, stability and regeneration capability. Additional, the satisfactory recoveries were also obtained in real samples of human serum, ranging from 92.83 % to 106.22 % with relative standard deviation (RSD) between 0.25 % and 1.85 %. The results possessed important reference value for exploring the application of DNA biosensor technology in the diagnosis of APOE gene mutation.
Mingyi Ma,Zhixiang Lv,You Li,Ziye Zhu,Chen Ling,Dawei He,Ruijiang Liu
Problem Unhealthy dietary habits and inadequate existing treatment technologies have led to high morbidity and mortality rates in patients with gastric cancer, and the research shows that curcumin has excellent antitumor properties, however, the non-water-soluble characteristic of curcumin limits its applications. To break the limitation, the targeted drug carriers become the urgent need to treat gastric cancer. Method The heterogeneous magnetic α-Fe 2 O 3 /Fe 3 O 4 nanoparticles were obtained by rapid combustion method with citric acid (CA) and ferric nitrate as raw materials and anhydrous ethanol as solvent and fuel, and then modified with citric acid (CA) and chitosan (CTS), and loaded curcumin (Cur) to form α-Fe 2 O 3 /Fe 3 O 4 -CA-CTS-Cur nanosystem. Results The particle sizes of heterogeneous magnetic α-Fe 2 O 3 /Fe 3 O 4 nanoparticles and α-Fe 2 O 3 /Fe 3 O 4 -CA-CTS-Cur nanosystem were 24.9 nm and 35.6 nm, respectively, and their respective saturation magnetization were 70.9 emu/g and 30.3 emu/g. The magnetic α-Fe 2 O 3 /Fe 3 O 4 -CA-CTS-Cur nanosystem had good stability, excellent drug release rate, and enhanced apoptosis to gastric cancer cells (SGC-7901) through the caspase pathway and ferroptosis of cells. Conclusions The magnetic drug delivery nanosystem was successfully constructed, and revealed significant inhibitory and killing effects on SGC-7901 cells, and low toxic and side effects on normal cells.
危险品化学品经营许可证（带存储）