高效液相色谱法测定化妆品中羟基积雪草苷和积雪草苷的含量

建立了一种使用高效液相色谱测定化妆品中羟基积雪草苷和积雪草苷含量的方法。样品经提取液超声提取后,用Acutfex PA-C₁₈色谱柱(250 mm×4.6 mm×5μm)分离,以体积比2:2:6的甲醇-乙腈-水作为流动相等度洗脱,流速1.0 mL/min,柱温35℃,检测波长205 nm。采用外标法测定,结果表明,积雪草苷和羟基积雪草苷在质量浓度5～100μg/mL内线性关系良好,方法的检出限为质量分数0.001 5%,定量限为质量分数0.005%。在不同类型的空白化妆品(水类、乳类、膏霜类)中进行加标回收试验,方法的回收率为82.8%～106%,相对标准偏差为0.94%～4.28%。该方法前处理简单,分离效率高,重复性好,准确度和精密度高,适用于化妆品中积雪草苷和羟基积雪草苷的测定。     

氧化铝脱色纯化羟基积雪草苷工艺研究

研究了氧化铝柱层析脱色纯化积雪草中羟基积雪草苷的工艺。以积雪草提取物为原料,水溶解后上氧化铝干柱,柱层析脱色来纯化制备高纯度羟基积雪草苷。最佳工艺路线为选用100～200目酸性氧化铝作为层析剂,洗脱剂选用30%乙醇,洗脱体积选用3BV,积雪草提取物质量与酸性氧化铝的用量比为1∶10。该工艺可简单有效地对含有羟基积雪草苷的溶液进行脱色纯化,得到澄清溶液,且平均回收率为93.61%,目标物成分不受损失。     

反相制备液相色谱分离纯化辣椒碱单体

用反相制备液相色谱法从辣椒碱类化合物中分离得到了高纯度辣椒碱单体.采用碳十八硅胶(ODS)柱(200 mm×10.0 mm),考察了流动相组成、进样浓度、进样体积和流动相流速等对分离的影响,确定了适宜的工艺操作条件:流动相为甲醇/水(75/25,v/v),进样浓度为180 mg·mL-1,进样体积为2.08 mL,流速为4.0 mL·min-1.在该工艺条件下,得到的辣椒碱单体纯度为95.23%,回收率为93.27%,产率为4.38 g·L-1·h-1,流动相消耗为0.087 L·g-1.本工艺操作简便,分离效率高,产品质量好,为辣椒碱单体的制备研究提供了一种新的方法.     

HPLC法测定双黄消炎片中黄芩苷的含量

建立高效液相法测定双黄消炎片中黄芩苷含量的方法。色谱柱为汉邦(4.60 mm×250 mm,5μm),流动相为甲醇-0.1%磷酸=(50∶50),流速1.0 mL·min-1;检测波长为274 nm。黄芩苷在17.6~176.0μg·mL-1浓度范围与峰面积呈良好的线性关系(R=0.9991),平均回收率为98.14%,RSD=0.99%。本方法简便、准确、专属性强、重现性好,可用于双黄消炎片中黄芩苷的含量测定。     

UPLC法测定绿豆中牡荆苷与异牡荆苷含量

建立了同时测定绿豆中牡荆苷与异牡荆苷含量方法:采用美国Waters ACQUITY UPLC系统,ACQUITY UPLC BEH C18(2.1 mm×50 mm,1.7μm)色谱柱;流动相:甲醇-0.5%冰醋酸溶液(20∶80);检测波长:338 nm;柱温:30℃;流速:1 mL/min;进样量:1μL。结果表明:该含量测定方法的精密度、稳定性、重复性、准确度良好,牡荆苷在0.685～6.85μg/mL,异牡荆苷在0.645～6.45μg/mL线性关系良好。三批样品中牡荆苷与异牡荆苷的平均含量为0.0467%和0.0555%。赤豆及黑豆中未检测到牡荆苷与异牡荆苷。所建立的含量测定方法快速、简便、准确,为绿豆解毒功效的物质基础研究提供质量控制方法。     

积雪草提取物对成纤维细胞胶原合成的影响

应用不同剂量的积雪草苷和羟基积雪草作用于体外培养成纤维细胞（Human Skin Fibroblast,HSFb）后，通过放射免疫的方法测定实验组和空白对照组细胞上清中Ⅰ型前胶原氨基端须原（PⅠNP）和Ⅲ型前胺原氨基端肽原（PⅢNP）含量。结果显示：①与空白对照组相比，积雪草苷和羟基积雪草苷可有效刺激体外培养HSFb PⅠNP和PⅢNP的分泌；②积雪草苷和羟基积雪草苷刺激靶细胞PⅠNP和PⅢNP分泌的生物学作用呈现明显的量效关系；③在10μg/mL～150μg/mL剂量内，Ad对HSFb刺激PⅠNP的分泌显示出比Md更强的生物活性（ρ＜0.01）。     

高效液相色谱法测定瘟疫消颗粒剂中黄芩苷的含量

采用高效液相色谱法测定瘟疫消颗粒剂中黄芩苷的含量,以Symmetry C18(3.9mm×150,5μm)为色谱柱,甲醇-0.2%磷酸水溶液(45∶55)为流动相,检测波长:280nm;流速:1.0mL·min-1;柱温:25℃.结果表明黄芩苷在0.0248～0.124 mg·mL-1范围内有良好的线性关系(r=0.9993),平均回收率为96.93%(RSD=0.92%).测得瘟疫消颗粒剂中黄芩苷的含量为9.0mg·g-1.该测定方法简单,专属性强,结果准确,重现性良好,可用于瘟疫消颗粒剂的质量控制.     

高效液相色谱法测定消炎利胆冲剂中芍药苷的含量

采用超声法提取消炎利胆冲剂中的芍药苷,建立了高效液相色谱法测定芍药苷含量的方法。采用Agilent ZORBAX SB-C18色谱柱(250mm×4.6mm,5μm),柱温26℃,流动相为0.2%磷酸溶液-甲醇(58∶42,体积比),流速1.0mL·min-1,检测波长230nm。结果表明:在2.016~336μg·mL-1的范围内芍药苷浓度与峰面积呈良好的线性关系,平均回收率为100.42%,RSD为0.97%。该方法简便、准确、重复性好,可用于消炎利胆冲剂中有效成分芍药苷的含量测定。     

积雪草提取物对皮肤细胞生物学特征的影响

通过体外培养角质形成细胞和成纤维细胞,应用XTT方法和流式细胞仪比较研究积雪草苷和羟基积雪草苷对靶细胞增殖和细胞周期的影响。结果显示,积雪草苷和羟基积雪苷在质量浓度高达200μg/mL时未见任何细胞毒性;对人皮肤角质形成细胞和成纤维细胞有明显促进增殖和DNA合成作用(p<0 05);积雪草苷比羟基积雪草苷有更强的生物活性(p<0 05)。     

HPLC法测定江西栀子中栀子苷含量研究

用HPLC法测定了江西栀子中栀子苷的含量。色谱柱：Kromasil C18柱（250 mm×416 mm,5μm）;流动相：乙腈-水（15∶85）流速：1.0 mL.min-1;检测波线性长：238 nm;柱温：30℃。结果：栀子苷进样浓度在6.4～32.0μg.mL-1范围内线性关系良好,线性方程为Y=29.802X＋3.75（r=0.9996）,平均回收率为为98.3%。江西不同产地的栀子中栀子苷含量范围在2.9%～3.8%,高于2010版药典规定。     

水镁石、水菱镁石和斜方云石资源、加工与应用

对水镁石、水菱镁石和斜方云石资源及其加工和应用进行了评述。包括上述资源的发展历史、化学组成和物性参数、资源储量和矿石品位、生产加工以及在不同领域(如镁质阻燃剂、中和剂、重金属离子脱除剂、镁肥、饲料添加剂等)的应用,并对它们的发展前景进行了展望。     

Pd-, Ni-, Fe-, and Co-Catalyzed Cross-Couplings Using Functionalized Zn-, Mg-, Fe-, and In-Organometallics

The development of new methods for preparing polyfunctional organometallics has made a broad range of such reagents available for various transition metal-catalyzed cross-couplings. An overview of the most general preparation methods will be presented. Applications to practical cross-coupling procedures will be covered, emphasizing the functional group compatibility and the reaction scope.     

Bioaerosol Science,Technology, and Engineering: Past,Present, and Future

Poor air hygiene as a result of bioaerosol contamination has caused diverse forms of adverse health effects and diseases. In addition, global biosecurity is threatened by purposeful use of biowarfare agents and the vulnerability of people to the infectious agents. Accordingly, developments in high-volume biosampling, including aerosol-to-hydrosol techniques with low cut-off size, real-time bioaerosol detection, adequate biological quantification, and exposure control, as well as the investigation of the link between disease outcome and bioaerosol exposure, are current areas of bioaerosol research. Although milestone progress has been achieved both in bioaerosol sampling and analysis techniques since late 1800s, compared to atmospheric chemistry the bioaerosol field is still understudied. This is partially because of the lack of both bioaerosol scientists and multidisciplinary collaboration. It is becoming necessary to develop a pool of scientists with different expertise, e.g., bioaerosol scientists, environmental engineers, biomedical engineers, epidemiologists, microbiologists, chemists, physicists, as well as researchers in other engineering fields, in mitigating bioaerosol-related adverse health effects, eliminating diseases, and preventing and controlling epidemic outbreaks. This work is conducted to broadly review current state-of-the-art sciences and technologies in the bioaerosol field. In tackling the challenges ahead, the review also provides perspectives for bioaerosol research needs, and further reminds bioaerosol scientists of those existing technologies in other fields that can be leveraged. In view of the past, forward-looking hypotheses and revolutional perspectives are needed to be formed in order to allow the bioaerosol research have major impacts in the academic community in this new millennium.     

Stable silyl, germyl, and stannyl cations, radicals, and anions: heavy versions of carbocations, carbon radicals, and carbanions

The rapidly growing chemistry of the cations, radicals, and anions based on the group 14 elements heavier than carbon (Si, Ge, Sn, and Pb) is one of the most important organometallic fields. Recent developments in this research area moved such species from the class of short-lived reactive intermediates to the class of easily accessible, isolable, and fully characterizable compounds. In this Account, we deal with the major accomplishments in the field of the stable representatives of "heavy" cations, radicals, and anions.     

Breaking, making, and twisting of chemical bonds in gas, liquid, and nanocavities

In this Account, we recount on our studies of 1'-hydroxy-2'-acetonaphthone (HAN, a proton transfer prototype molecule) in gas, solutions, and nanocavities. The internal H-bond photoreaction in HAN leads to a keto type structure, and following its formation, an internal twisting motion gives birth to keto rotamers. Theory, temperature, and solvent effects on its photodynamics show the involvement of efficient radiationless processes in both keto structures. When HAN is caged in a cyclodextrin nanocavity, the spectroscopy, photodynamics, and issues of twisting motion are strongly affected and could be tuned: a behavior relevant to those of many chemical and biological systems.     

Polystyrene nanocomposite materials: Preparation,morphology, and mechanical,electrical, and thermal properties

In this study, we prepared polystyrene (PS) resin nanocomposites with antistatic properties by melt‐blending PS with nanoscale zinc oxide (ZnO). The effects of nanoscale ZnO on the electrical and physical characteristics of the PS nanocomposites were investigated. Two kinds of nanoscale powders, spherical zinc oxide (s‐ZnO) and zinc oxide whisker (w‐ZnO), were selected. The coupling agents vinyltriethoxysilane (VTES) and phenyltriethoxysilane (PTES) were used to improve the compatibility between the nanopowders and PS resin. The addition of s‐ZnO and w‐ZnO improved the antistatic characteristics of the materials. The surface resistivities of the s‐ZnO and w‐ZnO nanocomposites were significantly reduced by modification with VTES and PTES. The addition of ZnO nanopowder increased the flexural modulus and reduced the flexural strength. The silane coupling agents improved the flexural properties of the nanocomposites. The glass‐transition temperatures and thermal degradation temperatures of the ZnO/PS nanocomposites increased with ZnO content. Treatment with silane increased the glass‐transition temperatures and thermal degradation temperatures of the composites. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2266–2273, 2005