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971.
972.
Highly selective, sensitive, and stable biosensors are essential for the molecular level understanding of many physiological activities and diseases. Electrochemical aptamer-based (E-AB) sensor is an appealing platform for measurement in biological system, attributing to the combined advantages of high selectivity of the aptamer and high sensitivity of electrochemical analysis. This review summarizes the latest development of E-AB sensors, focuses on the modification strategies used in the fabrication of sensors and the sensing strategies for analytes of different sizes in biological system, and then looks forward to the challenges and prospects of the future development of electrochemical aptamer-based sensors. 相似文献
973.
Cr3+-doped phosphors show significant application potential in near-infrared (NIR) light-emitting diodes (LEDs). However, the development of thermally stable and efficient NIR phosphors still faces enormous challenges. Herein, NIR phosphors K2NaMF6:Cr3+ (M3+ = Al3+, Ga3+, and In3+) were synthesized by the hydrothermal method. The represented K2NaAlF6:Cr3+ phosphor can be effectively excited by blue light (~430 nm) to present broadband emission at half a maximum of 96 nm peaking at ~ 728 nm. Meanwhile, the K2NaAlF6:Cr3+ phosphor exhibits excellent internal quantum efficiency (IQE = 68.08%) and nearly zero-thermal-quenching behavior, which is able to maintain 96.5% emission intensity at 150 °C of the initial value at 25 °C. The NIR phosphor-converted LED was fabricated based on K2NaAlF6:Cr3+ phosphor and a blue LED chip, showing a NIR output power of 394.39 mW at 300 mA with a high photoelectric conversion efficiency of 10.9% at 20 mA. Using the high-power NIR LED as a lighting source, transparent and quick veins imaging as well as non-destructive testing were demonstrated, suggesting the NIR phosphor has a wide range of practical applications. 相似文献
974.
Yan Zhou Jinjian Li Han Yuan Rui Su Yue Huang Yiyou Huang Zhe Li Yinuo Wu Haibin Luo Chen Zhang Ling Huang 《Molecules (Basel, Switzerland)》2021,26(10)
Phosphodiesterase 2 (PDE2) has been regarded as a novel target for the treatment of Alzheimer’s disease (AD). In this study, we obtained (R)-LZ77 as a hit compound with moderate PDE2 inhibitory activity (IC50 = 261.3 nM) using a high-throughput virtual screening method based on molecular dynamics. Then, we designed and synthesized 28 dihydropyranopyrazole derivatives as PDE2 inhibitors. Among them, compound (+)-11h was the most potent PDE2 inhibitor, with an IC50 value of 41.5 nM. The molecular docking of PDE2-(+)-11h reveals that the 4-(trifluoromethyl)benzyl)oxyl side chain of the compound enters the H-pocket and forms strong hydrophobic interactions with L770/L809/F862, which improves inhibitory activity. The above results may provide insight for further structural optimization of highly potent PDE2 inhibitors and may lay the foundation for their use in the treatment of AD. 相似文献
975.
ZHENG Gaofeng PENG Hao JIANG Jiaxin KANG Guoyi LIU Juan ZHENG Jianyi LIU Yifang 《高等学校化学研究》2021,37(3):571-577
Convenient and integration fabrication process is a key issue for the application of functional nanofibers. A surface functionalization method was developed based on coaxial electrospinning to produce ultraviolet(UV) protection nanofibers. The titanium dioxide(TiO2) nanoparticles suspension was delivered through the shell channel of the coaxial spinneret, by which the aggregation of TiO2 nanoparticles was overcome and the distribution uniformity on the surface of polyethylene oxide(PEO) nanofiber was obtained. With the content of TiO2 increasing from 0 to 3%(mass fraction), the average diameter of nanofibers increased from (380±30) nm to (480±100) nm. The surface functionalization can be realized during the electrospinning process to gain PEO/TiO2 composite nanofibers directly. The uniform distribution of TiO2 nanoparticles on the surface of nanofibers enhanced the UV absorption and resistance performance. The maximum UV protection factor(UPF) value of composite nanofibers reaches 2751. This work presented a novel surface-functionalized way for the preparation of composite nanofiber, which has great application potential in the field of micro/nano system integration fabrication. 相似文献
976.
977.
978.
建立了一种机械力化学提取法和实时直接分析质谱(DART-MS)分析相结合的中草药多糖分析方法,同时测定了黄芪、银耳、百合、茯苓、鼓槌石斛、金钗石斛、铁皮石斛和党参8种中草药多糖。比较了机械力化学提取(MCE)法与传统方法的提取效果,并优化了MCE法的提取参数。通过体积排阻色谱分离中草药多糖,建立分子质量校准曲线,估算了多糖分子质量。利用DART-MS直接裂解多糖大分子,可瞬时获得m/z<350的碎片离子,不同的中草药多糖得到的特征性的质谱离子峰可用于多糖样品的有效区分。该方法具有简单、快速、高通量、无需预消化的特点,是直接从复杂多糖大分子中获取特征指纹图谱的有力工具。 相似文献
979.
Laser-induced breakdown spectroscopy (LIBS) is an analytical detection technique based on atomic emission spectroscopy to measure the elemental composition. LIBS has been extensively studied and developed due to the non-contact, fast response, high sensitivity, real-time and multi-elemental detection features. The development and applications of LIBS technique in Asia are summarized and discussed in this review paper. The researchers in Asia work on different aspects of the LIBS study in fundamentals, data processing and modeling, applications and instrumentations. According to the current research status, the challenges, opportunities and further development of LIBS technique in Asia are also evaluated to promote LIBS research and its applications. 相似文献
980.