空间分辨荧光分析技术

空间分辨荧光分析技术突破了传统荧光分析的局限,为获得空间定位信息提供了技术保障。系统地综述了构成该技术的共焦荧光法、全内反射荧光法、多光子荧光法以及近场荧光法等4种方法的原理、特点、发展及其应用,并且强调了其在单分子测定中的作用。引用文献64篇。     

Formation Mechanism and Stability Study of Konjac Glucomannan Helical Structure

The formation mechanism and stability of konjac glucomannan (KGM) helical structure were investigated by molecular dynamic simulation and experimental method. The results indicate that the molecular conformation of KGM is a non-typical helical structure. In detail, helical structure of KGM is mainly sustained by acetyl group, whose size and stability are affected by the molecular polymerization degree of KGM. In vacuum among the non-bonding interactions, electrostatic force is the greatest factor affecting its helical structure, but in water solution, hydrogen bond affects the helical arrangement greatly. To our interest, temperature exhibits a reversible destroying effect to some extent; the helical structure will disappear completely and present a ruleless clew-like arrangement till 341 K. This work suggests that the method of combining molecular dynamic simulation and experiment tools can be effective in the study of KGM helical structure.     

Study on the Hydration Shell of Single-helical of Konjac Glucomannan

The local maxima of water density in the space near the single-helical of Konjac glucomannan as well as the dominant conformation of the system was studied by molecular dyna-mics under the water environment. The results indicate that the hydration shell,potential energy,and its hydrogen bond network with water bridges of the left-handed single-helix conformation was favored compared to those of right-handed single-helix conformation. This work suggests that the left-handed single-helix conformation was the dominant conformation of KGM in the water environment.     

超高效液相色谱-串联质谱法测定鸡肉中4种蛋白酶抑制剂

建立了鸡肉中4种蛋白酶抑制剂（沙奎那韦、利托那韦、奈非那韦、茚地那韦）的超高效液相色谱-串联质谱（UPLC-MS/MS）检测方法。样品经30%（v/v）乙腈水溶液（含1%（v/v）三氯乙酸）振荡提取、混合型阳离子交换MCX柱净化,采用Luna^® C8色谱柱（150 mm×2 mm,3 μm）,以0.2%（v/v）甲酸水溶液（含5 mmol/L乙酸铵）和乙腈为流动相进行梯度洗脱,采用电喷雾电离（ESI⁺）源和多反应监测（MRM）模式检测。结果表明,在0.1~20.0 μg/L范围内,4种目标化合物呈良好的线性关系,相关系数（r²）大于0.99,方法的定量限（S/N=10）为0.20~0.90 μg/kg;鸡肉组织中4种目标化合物在1.0、2.0和10.0 μg/kg 3个水平下的平均加标回收率为69.0%~106.0%,日内和日间相对标准偏差（RSD）为2.2%~13.8%（n=6）和3.6%~14.6%（n=3）。该法简单、高效、灵敏、准确,可用于鸡肉中沙奎那韦、利托那韦、奈非那韦、茚地那韦残留量的测定。     

卟啉全内反射同步荧光法测定蛋白质

应用全内反射与同步荧光相结合的技术,建立了利用蛋白质吸附在液-固界面上的同步荧光信号来测定本体蛋白质溶液浓度的新方法。其原理为meso-四(4-磺酸基苯基)卟啉(TPPS)标记牛血清蛋白(BSA)在石英界面的吸附后信号强度随本体溶液浓度的增加呈线性关系。方法的检出限是94 ng·mL-1。用于实际人血清蛋白样品的测定,结果令人满意。     

Effects of Irradiation on the Structure-activity Relationship of Konjac Glucomannan Molecular Chain Membrane

To know the effects of irradiation on the konjac glucomannan (KGM) molecular chain membrane, KGM membrane solution was treated with the irradiation dose of 0-20 kGy in this study, and the structure and properties of KGM membrane were analyzed with Infrared spectrum, Raman spectrum, X-ray, SEM scanning and so on. The results revealed that the effects of different irradiation doses on the KGM molecular chain structure were different. Higher irradiation dose (20 kGy) resulted in partial damage against KGM membrane crystal structure, and there was no obvious change for the amorphous structure; with membrane property test, the tensile strength of KGM membrane gradually increased with the increase of irradiation dose and its elongation at break reduced, but these changes were not significant, WVP value reduced; with SEM, the membrane surface treated with irradiation was smoother even than the membrane without treatment. In addition, when increasing the irradiation dose, membrane surface became more even, and arrangement was more orderly and compact. Irradiation modification could effectively improve the KGM membrane properties, and it is an ideal modification method.