173 research outputs found
A fast and low-cost spray method for prototyping and depositing surface-enhanced Raman scattering arrays on microfluidic paper based device
In this study, a fast, low-cost, and facile spray method was proposed. This method deposits highly sensitive surface-enhanced Raman scattering (SERS) silver nanoparticles (AgNPs) on the paper-microfluidic scheme. The procedures for substrate preparation were studied including different strategies to synthesize AgNPs and the optimization of spray cycles. In addition, the morphologies of the different kinds of paper substrates were characterized by SEM and investigated by their SERS signals. The established method was found to be favorable for obtaining good sensitivity and reproducible results. The RSDs of Raman intensity of randomly analyzing 20 spots on the same paper or different filter papers depositing AgNPs are both below 15%. The SERS enhancement factor is approximately 2 x 10(7). The whole fabrication is very rapid, robust, and does not require specific instruments. Furthermore, the total cost for 1000 pieces of chip is less than $20. These advantages demonstrated the potential for growing SERS applications in the area of environmental monitoring, food safety, and bioanalysis in the future
Manganese affects the growth and metabolism of Ganoderma lucidum based on LC-MS analysis
Background As a metal-enriched edible fungus, Ganoderma lucidum is capable of adsorbing manganese effectively. And the manganese ion is demonstrated to play an important role in the synthesis of manganese peroxidase (Mnp) and other physiological activities during G. lucidum growth. Recently, the influence of manganese on the metabolites of G. lucidum fruiting bodies can be revealed through metabonomics technique. Methods In this study, we uncovered the changes between the control and 200 mg/kg Mn-treated fruiting bodies with liquid chromatography coupled to mass spectrometry (LC-MS). Results The mycelial growth rate, dry yield, Mnp activity , total polysaccharide content, triterpenoid content, and total manganese content in the mature fruiting bodies of G. lucidum changed between the control and different Mn-treated groups. Based on LC-MS method, a total of 16 significantly different metabolites were obtained and identified, among which, five presented significantly down-regulated and 11 up-regulated in Mn-treated samples. The metabolites chavicol and palmitoylethanolamide were particularly significantly up-regulated, and were found the strong promotion relationship. Dependent on the MetPA database, four KEGG pathways were detected and glycerophospholipid metabolism was most impacted, in which, choline was involved in. Discussion The added manganese ion in the substrate enhanced Mnp activities, and consequently promoted the mycelial growth, yield , metabolites in the fruiting bodies including triterpenoids, total manganese, chavicol, etc. Our finding can provide a theoretical reference to regulation of manganese on the physiological metabolism of G. lucidum
Inflammatory factors and risk of meningiomas: a bidirectional mendelian-randomization study
BackgroundMeningiomas are one of the most common intracranial tumors, and the current understanding of meningioma pathology is still incomplete. Inflammatory factors play an important role in the pathophysiology of meningioma, but the causal relationship between inflammatory factors and meningioma is still unclear.MethodMendelian randomization (MR) is an effective statistical method for reducing bias based on whole genome sequencing data. It’s a simple but powerful framework, that uses genetics to study aspects of human biology. Modern methods of MR make the process more robust by exploiting the many genetic variants that may exist for a given hypothesis. In this paper, MR is applied to understand the causal relationship between exposure and disease outcome.ResultsThis research presents a comprehensive MR study to study the association of genetic inflammatory cytokines with meningioma. Based on the results of our MR analysis, which examines 41 cytokines in the largest GWAS datasets available, we were able to draw the relatively more reliable conclusion that elevated levels of circulating TNF-β, CXCL1, and lower levels of IL-9 were suggestive associated with a higher risk of meningioma. Moreover, Meningiomas could cause lower levels of interleukin-16 and higher levels of CXCL10 in the blood.ConclusionThese findings suggest that TNF-β, CXCL1, and IL-9 play an important role in the development of meningiomas. Meningiomas also affect the expression of cytokines such as IL-16 and CXCL10. Further studies are needed to determine whether these biomarkers can be used to prevent or treat meningiomas
Study of interaction between drug enantiomers and serum albumin by capillary electrophoresis
Catalytic Method Determination of Serum Transferrin by Capillary Electrophoresis
A high performance capillary electrophoresis (HPCE) catalytic method for the determination of serum transferrin concentration has been developed. The whole process includes techniques of pretreatment of serum samples and HPCE system optimization. For standard solution, a good linear response was maintained over the range 0. 5~10 µmol/L (r = 0. 995). Seven healthy adult serum samples were studied by this system and their transferrin concentrations are 23. 9, 25. 7, 26. 9, 24. 5, 23. 2, 25. 5 and 23. 7 µmol/L. 30 µL serum would be sufficient for transferrin measurement and the total serum pretreatment process takes less than 2 hours and the CE separation process takes only 6 min. This HPCE method is reliable, sensitive, rapid and efficient. Thus it is suitable for clinical application
Patterned Paper as a Low-Cost, Flexible Substrate for Rapid Prototyping of PDMS Microdevices via “Liquid Molding”
Bilirubin–human serum albumin interaction monitored by capillary zone electrophoresis
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