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The CYP2C19*2 gene carriers and non-carriers are closely related to the dosage of clopidogrel. To correctly guide the use of clopidogrel and promote individualized therapy, an ultra-sensitive electrochemical biosensor was developed for the detection of CYP2C19*2 gene. The heterogeneous α-Fe2O3/Fe3O4 nanosheets were prepared via the hydrothermal-calcination process, and the preparation parameters were optimized. The average diameter and thickness of the nanosheets were approximately 150 nm and 53 nm, respectively; and the saturation magnetization was 80.2 emu/g. The α-Fe2O3/Fe3O4@Au nanosheets were prepared by sodium borohydride reduction method, and self-assembled to the electrode surface with magnetic field. Ultra-sensitive detection of CYP2C19*2 gene was realized through the recognition ability of strong single base mismatching of peptide nucleic acid and signal amplification effect of magnetic α-Fe2O3/Fe3O4@Au nanosheets. Under optimal detection conditions, the current had a good linear correlation with the negative logarithm of CYP2C19*2 gene concentration in the range 1 pM—1 nM, and the detection limit was 0.64 pM (S/N = 3). Meanwhile, the electrochemical signals of target DNA and incomplete complementary DNA were detected. The constructed biosensor exhibited good selectivity, reproducibility, and stability, providing a promising strategy for the detection of other gene mutations by electrochemical biosensors. [ABSTRACT FROM AUTHOR]

A label-free electrochemical biosensor with magnetically induced self-assembly based on peptide nucleic acids (PNA) and Fe 3 O 4 /Fe 2 O 3 heteroplasmon nanorods was successfully fabricated to detect the single nucleotide polymorphism (SNP) of CYP2C9*3. The sensitivity of the electrochemical biosensor was improved by introducing PNA and Fe 3 O 4 /Fe 2 O 3 @Au nanocomposites. The Fe 3 O 4 /Fe 2 O 3 @Au nanocomposites were assembled on the surface of the magnetic glassy carbon electrode (MGCE) by magnetic field, and the thiolated PNA were connected to the nanocomposites through Au-S bonds. The electrochemical biosensor could recognize single-base mismatch DNA. • A label-free electrochemical biosensor with magnetically induced self-assembly was fabricated. • PNA were utilized as the capture probes to detect SNP of CYP2C9*3 gene. • The novel Fe 3 O 4 /Fe 2 O 3 @Au nanocomposites are applied in the signal amplification strategy of this biosensor. A label-free electrochemical biosensor with magnetically induced self-assembly based on peptide nucleic acids (PNA) and Fe 3 O 4 /Fe 2 O 3 heteroplasmon nanorods was successfully fabricated to detect the single nucleotide polymorphism (SNP) of CYP2C9*3. The sensitivity of the electrochemical biosensor was improved by introducing PNA and Fe 3 O 4 /Fe 2 O 3 @Au nanocomposites. The Fe 3 O 4 /Fe 2 O 3 @Au nanocomposites were assembled on the surface of the magnetic glassy carbon electrode (MGCE) by magnetic field, and the thiolated PNA were connected to the nanocomposites through Au-S bonds. The biosensor exhibited a good linear correlation between 1 pM and 1 µM (R2 = 0.9941), and the limit of detection (LOD) and the limit of quantitation (LOQ) were 0.95 pM and 3.18 pM, respectively. Besides, the electrochemical biosensor could recognize single-base mismatch DNA, and it could be stored stably for 15 days at 4 °C. [ABSTRACT FROM AUTHOR]

A "turn-on" aptasensor for label-free and cell-free EpCAM detection was constructed by employing magnetic α-Fe 2 O 3 /Fe 3 O 4 @Au nanocomposites as a matrix for signal amplification and double-stranded complex (SH-DNA/Apt probes) immobilization through Au-S binding. α-Fe 2 O 3 /Fe 3 O 4 @Au could be efficiently assembled into uniform and stable self-assembly films via magnetic-induced self-assembly technique on a magnetic glassy carbon electrode (MGCE). The effectiveness of the platform for EpCAM detection was confirmed through differential pulse voltammetry (DPV). Under optimized conditions, the platform exhibited excellent specificity for EpCAM, and a strong linear correlation was observed between the current and the logarithm of EpCAM protein concentration in the range 1 pg/mL-1000 pg/mL (R 2 = 0.9964), with a limit of detection (LOD) of 0.27 pg/mL. Furthermore, the developed platform demonstrated good stability during a 14-day storage test, with fluctuations remaining below 93.33% of the initial current value. Promising results were obtained when detecting EpCAM in spiked serum samples, suggesting its potential as a point-of-care (POC) testing., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Magnetic Ni 0.4 Co 0.2 Zn 0.4 Fe₂O₄ nanoparticles were prepared via the rapid combustion process, the morphology and magnetic property of them were investigated by SEM, TEM, XRD, VSM, and FTIR. The as-prepared magnetic Ni 0.4 Co 0.2 Zn 0.4 Fe₂O₄ nanoparticles calcined at 400 °C for 2 h with absolute alcohol of 20 mL were characterized with the average nanoparticle size of around 25 nm and the specific magnetization of 35.2 emu/g. The adsorption kinetics and adsorption isotherms of Congo red (CR) from aqueous solutions onto Ni 0.4 Co 0.2 Zn 0.4 Fe₂O₄ nanoparticles were investigated by UV spectroscopy at room temperature; the adsorption kinetics data were in good agreement with the pseudo-second-order kinetic model in the initial CR concentrations of 200-500 mg/L. By comparison of Langmuir, Freundlich and Temkin models for adsorption isotherms of CR, the Temkin model (correlation coefficient R ₂ = 0.9969) could be used to evaluate the adsorption isotherm of CR onto the magnetic Ni 0.4 Co 0.2 Zn 0.4 Fe₂O₄ nanoparticles at room temperature, which suggested that the adsorption of CR onto the magnetic Ni 0.4 Co 0.2 Zn 0.4 Fe₂O₄ nanoparticles was a hybrid of monolayer and multilayer absorbing mechanism.

Diabetes mellitus is a serious disease endangering human health worldwide. Vitamin D (Vit D) is a well-characterized regulator of calcium-phosphorus metabolism that also exerts other biological effects extending far beyond mineral homeostasis. Some epidemiological studies have suggested that Vit D has a role in defense against diabetes, although the mechanism remains unclear. Autophagy, an intracellular catabolic process, is necessary to maintain the normal structure and function of host cells. In our previous study, we found that Vit D could induce autophagy of pancreatic beta cells and prevent insulitis, although the underlying mechanisms remain to be fully elucidated. In this study, the protective effect of 1,25(OH) 2 D 3 , the physiologically active metabolite of Vit D, against streptozotocin-induced cytotoxicity in rat insulinoma cell line (INS-1) cells was explored. Cell viability and insulin secretion of INS-1 cells in response to different treatments were measured with a cell counting kit and enzyme-linked immune absorbent assay (ELISA), respectively. In addition, malondialdehyde (MDA) content and total antioxidant capacity (T-AOC) were measured by ELISA. RT-PCR and Western blot analyses were used to detect autophagy levels, reactive oxygen species (ROS) was assessed by fluorescence microscope, ultrastructure analysis was performed using transmission electron microscopy. The results demonstrated that 1,25(OH) 2 D 3 could increase cell viability and insulin secretion of INS-1 cells, and protected cells from oxidative damage induced by streptozotocin (STZ) through autophagy activation. These findings shed light on mechanisms underlying the ameliorative effects of Vit D on diabetes mellitus.

Magnetic core-shell structure (1-x)Ni0.5Zn0.5Fe2O4/xSiO2 (x = 0-0.2) nanopowders were successfully prepared via the methanol combustion process, the as-prepared magnetic core-shell structure nanopowders were characterized by XRD, SEM, TEM, HRTEM, BET, and VSM techniques, and the adsorption performance of DNA onto them was investigated. The results showed that the magnetic core-shell structure 0.9Ni0.5Zn0.5Fe2O4/0.1SiO2 nanopowders exhibited a good adsorption capacity of DNA, and the adsorbance of DNA for magnetic core-shell structure 0.9Ni0.5Zn0.5Fe2O4/0.1SiO2 nanopowders was enhanced to 2.8 times for Ni0.5Zn0.5Fe2O4 nanoparticles. The adsorption kinetics of DNA in aqueous solution onto the magnetic core-shell structure 0.9Ni0.5Zn0.5Fe2O4/0.1SiO2 nanopowders at room temperature were investigated, and the kinetics data were in good agreement with the pseudo-first-order kinetic model in the initial DNA concentration of 50 μg/mL.

Magnetic Ni0.5Zn0.5Fe2O4/SiO2 nanocomposites were prepared via the solution combustion process, their structure and magnetic properties were investigated by XRD, SEM, TEM and VSM. The asprepared magnetic Ni0.5Zn0.5Fe2O4/SiO2 nanocomposites were characterized with the average grain size of about 20 nm, the specific magnetization of 31.6 Am2/kg, and the specific surface area of 117.0 m2/g. The adsorption kinetics of bovine serum albumin (BSA) from aqueous solution onto the magnetic Ni0.5Zn0.5Fe2O4/SiO2 nanocomposites at room temperature was investigated. The kinetics data related to the adsorption of BSA from aqueous solutions were in good agreement with the pseudo-second-order kinetics model in the initial concentrations of 0.2-0.8 mg/mL.

Primary Sjögren's syndrome (pSS) is a common autoimmune disease involving abnormal Th17 activation. The aim of the current study was to investigate the immunosuppression effect of Cyclosporine A (Cys A), a potent immunosuppressor on the proliferation and activation of T cells, on the activation of Th17 cells. Blood samples from both inactive and active pSS patients as well as healthy controls were collected and serum and peripheral blood mononuclear cells (PBMCs) were collected and tested for IL-17 and RORγt expression. Subsequently, PBMCs were treated in vitro with Cys A in a series of doses and incubation time and the effect of Cys A on inhibiting Th17 activation was tested by measuring IL-17 and RORγt expression. IL-17 in both serum and PBMCs as well as RORγt in PBMCs from active pSS patients were significantly elevated on both the mRNA and protein levels comparing to those from both inactive pSS patients and healthy controlCys A in the final concentration of 80ng/ml and the treatment time of 24h showed strong inhibition effect on the expression of IL-17 and RORγt in PBMCs from active pSS patients. However, Cys A in various doses and incubation times did not show much impact on inhibiting IL-17 as well as RORγt expression in PBMCs from healthy donors and inactive pSS patients. Cys A possesses the capability in immunosuppressing the activation of Th17 cells, suggesting that Cys A may be a potential treatment for pSS and maybe other autoimmune diseases.