HP LC测定处方中大黄素和大黄酚的含量

建立测定处方中大黄素和大黄酚含量的高效液相色谱法。固定相为依立特C_(18)柱(5μm,4.6 mm×250 mm),流动相为甲醇-0.1%磷酸溶液(85∶15,V/V),流速为1 mL/min;柱温为30℃,检测波长为240 nm。大黄素和大黄酚分别在进样量为0.0508～0.2540μg和0.1419～0.7095μg范围内与峰面积呈线性关系;平均回收率分别为98.71%(RSD=1.37%)和98.52%(RSD=1.31%);含量分别为12.1856 mg/g和19.5257 mg/g。该方法结果准确,重现性好,可作为该方质量控制的定量方法之一。     

高效液相色谱法测定化妆品中芦荟蒽醌类的含量

建立了同时测定化妆品中蒽醌类含量的HPLC法,以评价化妆品的美容功效。采用甲醇超声提取,HPLC法分离测定。结果为3种被测物在11 min内均得到良好的分离。在1μg/mL~250μg/mL均与其各自对应的峰面积呈良好线性关系(R>0.999 7),在添加质量浓度为0.5μg/mL~5.0μg/mL,回收率在92.0%~102.5%,精密度RSD<2.1%,最低检出限(S/N=3)为芦荟苷0.516 0μg/mL,芦荟大黄素0.086 4μg/mL,大黄酚0.101 6μg/mL。该法简便、快速、准确,可用于化妆品中蒽醌类含量的检测。     

HPLC测定清火片中大黄素和大黄酚的含量

目的建立HPLC法清火片中大黄素和大黄酚的含量测定方法。方法采用Phenomenex Luna C18色谱柱;甲醇-0.1%磷酸溶液(85:15)为流动相;流速为0.8mL.min-1;检测波长:254nm。结果大黄素和大黄酚与其相邻质峰能完全分离,大黄素在2.1～42ug.mL-1浓度范围内线性关系良好,r=1.0000;大黄酚在4.94~98.8ug.mL-1浓度范围内线行关系良好,r=0.9999。平均回收率大黄素为98.7%,RSD=1.82%、大黄酚为99.2%,RSD为1.71%。结论本方法简便、准确、重现性好,能排除其他成分的干扰,可用于该制剂的质量控制的评价。     

HPLC法测定原料中丹皮酚含量的研究

建立了测定原料中丹皮酚含量的高效液相色谱方法.采用Agilent ODS C18(250 mn×4.6 mm,5μm)色谱柱,以纯水—甲醇(体积比为27∶73)为流动相,流速为1.0 mL/min,柱温35℃,在274 nm用紫外检测器进行检测.结果表明,重复测定结果的相对标准偏差在0.4％,回收率在95 ％～105％范围内.该方法的灵敏度高,准确性和重现性良好,有效消除了样品中其他组分对目标峰的干扰,线性范围宽,分离度好,可用来准确分析原料中丹皮酚的含量.     

大黄中大黄酚的提取工艺研究

以大黄为原料,研究不同提取工艺对大黄中大黄酚提取效果的影响,采用高效液相色谱法测定其含量。结果表明,大黄酚最佳提取工艺为：以10倍量80％乙醇回流提取,每次2h,大黄酚含量最高。该工艺简便、易行,可用于大黄中大黄酚的提取。     

HPLC法测定火麻仁中大麻二酚的含量

本文采用HPLC法对中药火麻仁中大麻二酚进行含量测定。确定色谱条件为：色谱柱Agilent E-clipse XDB-C18（150mm×4.6mm,5μm）;流动相甲醇-水（体积比为78∶22）;流速1.0mL·min^-1;检测波长220nm;柱温25℃。在此条件下,大麻二酚与其它组分得到良好的分离,线性范围为0.04～0.40μg（r=0.9981）,平均加样回收率为95.3%（RSD=0.77%）。     

液质联用法测定化妆品中3种蒽醌类化合物的含量

建立了液相色谱-串联质谱联用测定化妆品中3种芦荟蒽醌类化合物含量的方法。样品经甲醇超声提取,用高效液相色谱分离后,采用电喷雾串联质谱进行定性和定量检测。方法线性范围为10~100 ng/mL,相关系数r大于0.99,最低检出限为3 ng/mL(S/N=3),高、中、低3个浓度水平的加标回收率在80.4%~95.2%之间,测定值的相对标准偏差(n=6)小于10%。     

高效液相色谱法测定胆清胶囊中大黄素含量的研究

采用高效液相色谱法，对制剂中大黄所含大黄素的含量测定进行了方法研究。实验结果表明，本法快速、简便、回收率高，结果准确可靠。     

HPLC法测定厚朴叶中厚朴酚与和厚朴酚

本文建立了高效液相色谱法同时测定厚朴叶中厚朴酚与和厚朴酚含量的方法。该方法准确、专属性强,可用于厚朴叶的定量分析。     

HPLC法测定糯米藤中槲皮素和山柰酚的含量

建立测定糯米藤中槲皮素和山柰酚含量的方法.采用HPLC法测定糯米藤中槲皮素和山柰酚的含量.色谱柱为X-Peonyx C18柱(250 mm×4.6 mm,5μm),流动相为甲醇-0.1％磷酸(55:45),检测波长为360 nm,流速1.0 mL·min-1,柱温30℃,进样量为10μL.槲皮素和山柰酚的进样量分别在0...     

超临界CO2萃取大黄总蒽醌工艺研究

对大黄游离蒽醌的超临界萃取工艺进行了优化,确定最优萃取工艺条件为:静萃取时间60 m in,动萃取时间30 m in,夹带剂乙醇相对大黄用量3 mL/g,萃取温度45℃,萃取压力45 MPa。然后分别采用无机酸和生物酶对大黄结合蒽醌进行水解,以提取总蒽醌。结果表明:当盐酸浓度为5 mol/L,淀粉酶质量浓度为2 g/L,纤维素酶质量浓度为1 g/L时,大黄结合蒽醌的糖苷键达到最优水解,此时总蒽醌质量分数分别为2.46%、2.33%和2.23%。     

超声波辅助萃取-高效液相色谱法测定化妆品中硫氯酚

建立超声波辅助萃取一高效液相色谱（HPLC）测定化妆品中硫氯酚含量的分析方法。试样经饱和氯化钠溶液分散,乙腈超声提取后,以甲醇一乙腈一乙酸铵缓冲溶液为流动相,经C18柱分离后进行HPLC检测。硫氯酚在0．5～25mg／L范围内呈良好的线性关系,线性相关系数大于0．999。5、10、50mg／kg3个浓度加标水平的平均回收率为95．2％一103．6％,相对标准偏差（RSD,n=6）为1．18％～2．55％,检出限为1．2mg／kg。该方法灵敏度高、重现性好、定量准确。     

Fabrication of a polymer monolithic column via redox system and its application in efficient separation of Chinese herb Rheum palmatum L.

A polymer monolithic column was prepared via redox system in a stainless steel column (50 × 4.6 mm i.d.) by using 1,6‐hexanediol diacrylate as monomer and ethylene dimethacrylate as cross linking agent. Characteristics of the homemade monolithic column were investigated by scanning electron microscopy, nitrogen adsorption‐desorption and mercury intrusion porosimeter, respectively. The results showed that the resulting monolithic column occupied relative uniform porous skeleton structure. Furthermore, the monolith was tested by separating aromatic compounds in conjunction of high performance liquid chromatography with the highest column efficiency of more than 21,000 plate per meter, which was relative high for polymer‐based monolithic column with 4.6 mm i.d. At last, the monolithic column was used to simultaneously separate and quantitatively analyzes five active compounds in Chinese herb Rheum palmatum L. The validation of the method was carried out, which indicated that the accuracy represented by recovery was in the range of 98.48% to 101.57%. Limit of detection and limit of quantification for the five active compounds were less than 33.7 ng and 90.8 ng, respectively. All the results indicated that the present method was simple and efficient for quantitative analysis of the five active compounds from Chinese herb Rheum palmatum L. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44874.     

固相萃取-高效液相色谱法测定水中氯酚类

采用固相萃取-高效色谱法测定水中酚类。通过正交试验和验证试验探讨固相萃取技术富集水中7种酚类各种因素的影响,优化固相萃取的条件。优化得到的固相萃取条件：样品的pH为2、选择Oasis HLB固相萃取色谱小柱、流速为5mL／min、洗脱溶剂为四氢呋喃、洗脱体积为2mL,分2次洗脱。使用该方法的加标回收率为94．2％～105．1％,相对标准偏差为1．2％～3．9％,检出限为0．1～0．5μg／L。固相萃取-高效液相色谱法不仅各组分的回收率和灵敏度高,而且具有操作简便、溶剂用量少的特点,符合水中酚类测定的要求。     

DPPH法评价大黄提取物的抗氧化活性

采用超声波法提取大黄抗氧化物质,以DPPH法评价大黄抗氧化活性。结果表明,大黄抗氧化物质最佳提取工艺为:以70%乙醇为溶剂,料液比为1∶40 g/mL,超声提取2次,每次提取30 min;大黄抗氧化活性物质主要分布于石油醚和乙酸乙酯提取物,为该药材的开发提供参考。     

HPLC法同时测定发酵液中纽莫康定Ao与Bo的含量

采用HPLC方法同时测定发酵液中纽莫康定A。与＆的含量。色谱柱为SepaxSapphireC,8（4．6mm×250rrlm,5“m）,流动相为甲醇一水（体积比45：55,内含0．1‰三氟乙酸）,流速为1．OmL·min＾－1,紫外检测波长为214rim。结果表明,纽莫康定A。与B0的浓度分别在47．5～191．4pg·mL。和38．4～153．6肛g·mL-1的范围内,与峰面积呈良好的线性关系（R分别为0．9997和0．9998）;检测灵敏度分别为6．86ng、5．95ng;平均回收率分别为99．15％（RSD一0．96％,n一9）和99．31％（RSD=0．98％,n一9）。该方法简便、准确、重现性好,可用于发酵液中纽莫康定A。与B0含量的测定。     

HPLC法测定猪尿酸酶活性

建立了一种测定重组猪尿酸酶活性的高效液相色谱方法。将重组猪尿酸酶基因工程菌的粗酶液与尿酸溶液反应5min,加入高氯酸溶液终止,经超滤后以体系中尿酸浓度的降低值为指标,采用HPLC法[色谱条件：AgilentZorbax 300SB-C18色谱柱、流动相为磷酸-甲醇-双蒸水（3∶25∶472,体积比）、流速1.0mL·min-1、波长292nm]测定粗酶液活性。结果表明,尿酸在10～500μmol·L-1范围内线性关系良好,样品回收率在99%～104%之间。该方法不受杂质干扰、稳定、灵敏度高,适用于尿酸酶粗酶液活性的检测。     

四氟苯甲酸反相高效液相色谱法分离条件的探索

研究了含氟有机酸的高效液相色谱分析方法,应用反相C18色谱柱,以15%甲醇/85%(20mmol/L KH2PO4缓冲溶液pH=2.3)为流动相,流速为1.0mL/min,紫外检测波长276nm。探索了流动相的选择,并考察了此方法的线性关系,回归方程及相对标准偏差,实验表明,在选定色谱条件下,此方法能较好地解决四氟苯甲酸的定量分析问题。     

Anti-Psoriatic Effect of Rheum palmatum L. and Its Underlying Molecular Mechanisms

Psoriasis is a chronic, immune-mediated inflammatory skin disorder. Rheum palmatum L. is a common traditional medicinal herb with anti-inflammatory and immunomodulatory activities. This study aimed to investigate the anti-psoriatic effects of the ethanolic extract from R. palmatum L. (RPE) and its chemical constituents, as well as the mechanisms underlying their therapeutic significance. An imiquimod (IMQ)-induced psoriasis-like mouse model was used to examine the anti-psoriatic effect of RPE in vivo. Network pharmacological analysis was performed to investigate the potential targets and related pathways of the RPE components, including rhein, emodin, chrysophanol, aloe-emodin, and physcion. The anti-inflammatory effects and underlying mechanisms of these components were examined using in vitro models. Topical application of RPE alleviated psoriasis-like symptoms and reduced levels of inflammatory cytokines and proliferation markers in the skin. Network pharmacological analysis revealed that RPE components target 20 genes that are linked to psoriasis-related pathways, such as IL-17, MAPK, and TNF signaling pathways. Among the five components of RPE, rhein and emodin showed inhibitory effects on TNF-α and IL-17 production in EL-4 cells, attenuated the production of CXCL8, CXCL10, CCL20, and MMP9, and reduced proliferation in HaCaT cells. Chrysophanol, aloe-emodin, and physcion were less effective than rhein and emodin in suppressing inflammatory responses and keratinocyte proliferation. The effects of these compounds might occur through the inhibition of the ERK, STAT3, and NF-κB signaling pathways. This study suggested the anti-psoriatic effect of RPE, with rhein and emodin as the main contributors that regulate multiple signaling pathways.