Fuzzy关系方程(Q～)uv·(X～)vw=(S～)uw的两个推论及其应用

证明了Fuzzy关系方程(Q～)uv·(X～)vw=(S～)uw的一个推论不成立,给出了Fuzzy关系方程(Q～)uv·(X～)vw=(S～)uw的两个新的推论,推广了Fuzzy关系方程的一个定理.     

HPLC测定当归中1-(3',4'-dihydroxycinnamoyl)-cyclopentane-2,3-diol的含量

目的 建立HPLC测定当归中1-（3'',4''-dihydroxycinnamoyl）-cyclopentane-2,3-diol含量的方法。方法 采用Inertsil ODS-3 C₁₈柱（4.6 mm×250 mm,5 μm）,流动相为乙腈-0.05%三氟乙酸水溶液梯度洗脱,流速为1.0 mL·min^-1,检测波长为325 nm,柱温为30℃。结果 1-（3'',4''-dihydroxycinnamoyl）-cyclopentane-2,3-diol进样量在0.023 36~1.168 0 μg（r=1.000 0）内与峰面积呈良好的线性关系,平均回收率为95.33%,RSD为1.88%。结论 该方法简便、准确、重复性好,可为当归药材的质量控制提供参考。     

Prediction of Poly(Ethylene) Glycol-Drug Eutectic Compositions Using an Index Based on the van't Hoff Equation

Purpose. To define an index based on the van't Hoff equation that can be used as a screening tool for predicting poly(ethylene) glycol (PEG)-drug eutectic composition. Methods. Phase diagrams of PEG with ritonavir, ibuprofen, fenofibrate, naproxen, and griseofulvin were constructed using differential scanning calorimetry, hot stage microscopy and powder X-ray diffractometry. Previously reported phase diagrams were also used to test the predictive capability of the index. Results. This work shows that a modified van't Hoff equation can be used to model the drug liquidus line of these phase diagrams. The slope of the liquidus line depends on the melting point (T^f _d) and heat of fusion (H^f _d) of the drug and describes the initial rate at which the eutectic or monotectic point is approached. Based on this finding, a dimensionless index I_c was defined. The index can be calculated from the melting points of the pure components and heat of fusion of the drug. In addition to the compounds listed above, the index was found to predict the eutectic composition for flurbiprofen, temazepam and indomethacin. These compounds range over 150°C in T^f _d, and from 25-65kJ/mole in H^f _d. Conclusion. Using I_c the approximate eutectic composition for eight different compounds was predicted. The index provides a useful screening tool for assessing the maximum drug loading in a drug-polymer eutectic/monotectic formulation.