固相萃取技术及其在体内药物分析中的应用

目的了解固相萃取技术的新进展及其在体内药物分析中的应用情况。方法介绍固相萃取基本原理、填料种类和自动化操作等,并对该技术在体内药物分析中的应用进行综述。结果与结论固相萃取技术萃取回收率高、易于自动化,能有效去处样品中的杂质,适于体内药物分析中生物样品的预处理。     

盐析辅助分散液液微萃取毛细管电泳测定口服液中甜味剂和防腐剂

目的 采用盐析辅助分散液液微萃取(SADLLME)-大体积样品堆积(LVSS)-毛细管电泳(CE)法测定阿斯巴甜、糖精、安赛蜜三种甜味剂以及苯甲酸、山梨酸两种防腐剂。方法 将待测溶液进行盐析液液微萃取处理后进行CE分析测定,设定电泳条件为：进样压力50 mbar,进样时间为 120 s,正常极性下分离电压为 20 kv,检测波长为 214 nm,分离温度为 25 °C。 结果 该方法在0.05~1.00 μg/mL范围内线性关系良好,最低检测限为2.5 ng/mL~10 ng/mL。萃取重现性良好(RSD小于10 ％,n=5)。待测组分富集倍数达到657~1674,富集效果良好。把该方法应用于不同种类口服液进行食品添加剂含量的测定,均获得了满意的结果。结论 实验表明使用微萃取与在线富集结合的手段更为高效、快速,能获得更高的富集倍数,成为提高毛细管电泳灵敏度的一种可靠方法。     

液液萃取-HPLC法和在线萃取-HPLC法测定卡马西平血药浓度的比较研究

目的比较卡马西平血药浓度监测的常规液液萃取-HPLC法和在线萃取-HPLC法的优缺点。方法液液萃取-HPLC法：以叔丁基甲醚为萃取溶剂,普萘洛尔为内标,分析柱为UltimateC18（51μm,4．6×250mm2）．流动相为乙腈-含0.3％甲酸的0．3％醋酸铵溶液（34：66）,检测波长为286nm,流速为1．0ml／min：在线萃取-HPLC法：以6％高氯酸溶液为蛋白沉淀剂在线萃取,预柱为VenusilC18（5tzm,4．6×30mm2）,分析柱为VenusilC18（5lxm,4．6×250mm2）,流动相为乙腈-0.3％醋酸铵溶液（40：60）,检测波长为286nm,流速为1．0ml／min。结果卡马西平在3．07—15．05μg／ml范围内线性良好．用液液萃取一HPLC法测定时r=0．9995,最低检测限为100ng／ml,回收率〉92．0％,日内RSD〈2．25％,日间RSD〈2．52％：用在线萃取一HPLC法测定时r=0．9999,最低检测限为30ng／ml,回收率〉103．8％,日内RSD〈1．21％,日间RSD〈1．21％。结论液液萃取-HPLC法灵敏度较低,操作较繁琐,溶剂消耗大,不宜于大批量样品测定;在线萃取-HPLC法灵敏度高,简单快速,稳定性强,易于实现质控．适用于低浓度的大批量样品的测定。     

液质联用技术在药物体内代谢研究中的应用

目的:探讨液质联用(LC-MS)接口技术研究及其在药物代谢中的应用。方法:查阅文献、综述液质联用接口技术研究及其在药物代谢中的应用。结果:随着各种新型接口技术,特别是电喷雾电离和大气压化学电离的引入,LC-MS技术对高极性化合物的分析具独特优势,在药物体内代谢研究中发挥着日趋重要的作用。结论:LC-MS技术在中药、抗菌药物等多种药物及其代谢物的分析检测中广泛的发挥着重要作用。     

液相微萃取技术及其在生物样品预处理中的应用进展

液相微萃取是在液相萃取技术基础上发展起来的新型生物样品前处理技术,具有简便、快速、经济、环保等特点,已在血液、尿液、唾液等生物基质样品分析中广泛应用。本文通过查阅近5年文献,对液相微萃取技术的主要模式,即单液滴微萃取、分散液-液微萃取和中空纤维液相微萃取的基本原理,以及其在生物样品预处理中的应用进展进行综述,以期为体内药物分析、药代动力学研究以及新药研发等领域样品前处理提供技术支撑和参考。     

利用液液萃取降低莫西克汀杂质含量的研究

利用莫西克汀杂质在不同溶剂中溶解度不同,利用不相溶的极性和非极性的两相溶剂进行液液萃取来降低莫西克汀中的A杂质、E+F杂质含量。结果显示在20~25℃环境下,30%甲醇溶液和庚烷溶解的粗品溶液效果最佳,最佳萃取次数为等体积萃取3次。     

液-液-液三相萃取苯氧甲基青霉素的研究

液-液-液三相萃取是针对复杂体系分离纯化的一种新技术．本文对比考察了传统两相体系与聚乙二醇-硫酸铵-乙酸丁酯构筑的三相体系对苯氧甲基青霉素滤液萃取行为及效果．重点考察了体系pH对苯氧甲基青霉素在三相萃取体系相间的分配规律。结果表明采用三相体系萃取苯氧甲基青霉素发酵滤液不需加入破乳剂．下相中乙酸丁酯的含量明显降低．而且色素在中间相富集，可以达到纯化有机相，简化工艺流程的效果。三相体系的pH对苯氧甲基青霉素在相间的分配有显著的影响．随着体系pH的降低．上相与下相分配系数Dt/b、上相与中相分配系数Dt/m显著增加．而中相与下相分配系数Dm/b呈缓慢下降趋势；当pH降低到3．0以下时．苯氧甲基青霉素在上相的质量分数达到90％以上．萃取率的变化比较平缓。     

液液平衡手性萃取拆分的研究进展

目的 介绍液液平衡手性萃取拆分技术的基本原理,总结近年来液液平衡手性萃取拆分的研究进展。方法 根据手性选择剂的分类,对近年来液液平衡手性萃取拆分的最新应用研究情况做了介绍。结果 总结归纳了5大类手性选择剂的应用,包括过渡金属络合物、酒石酸衍生物、冠醚类、β-环糊精衍生物及金鸡纳碱类,并简要介绍了液液萃取拆分相关模型研究。结论 液液平衡手性萃取拆分技术分离效果良好,适用性强,易于实现工业规模,有望成为制备型分离外消旋体化合物的先进技术。     

体内药物分析中色谱技术的应用

本文综述了国内外用于体内药物分析的一些新兴色谱技术,如超临界流体色谱法、毛细管电泳法、手性色谱法、胶束色谱法、分子生物色谱法、色谱固相微萃取联用法、色谱-质谱联用法、色谱-色谱联用法等的具体应用进展;展望了色谱技术在体内药物分析应用中的前景及其发展方向,即开发新的检测技术及借助计算机手段,以实现其连续化、自动化、联用化及智能化。     

固相萃取技术及其在体内药物分析中的应用

目的：了解固相萃取技术进展及应用情况。方法：从萃取机制、方法建立和萃取装置等对固相萃取技术进行综述，并对近年来该技术在体内药物分析方面的应用作了介绍。结果和结论：固相萃取技术萃取回收率高、易于自动化，能有效去除样品中的杂质等，适于生物样品的预处理。     

伊曲康唑自乳化液的制备及质量评价

目的:制备伊曲康唑自乳化液并对其进行质量评价。方法:通过溶解度试验,油相与各种乳化剂、助乳化剂的配伍选择筛选自乳化液的处方。考察该乳化液经水稀释后形成微乳的形态、粒径和Zeta电位,并测定载药量。结果:该自乳化液处方为油相维生素E醋酸酯,乳化剂TranscutolP,助乳化剂CremophorRH40,三者比例为3:12:5。微乳在透射电镜下呈球形,分布均匀,粒径为(296.1±90.7)nm,Zeta电位为(—13.2±1.6)mV,载药量为9.88%。结论:所制自乳化液质量稳定可靠。     

Thermo-/pH-dual responsive properties of hyperbranched polyethylenimine grafted by phenylalanine

Novel thermo- and pH-dual responsive amphiphilic copolymers were synthesized based on hyperbranched polyethylenimine (PEI) by grafting l-phenylalanine. The phenylalanine-modified PEI exhibited lower cytotoxicity than commercial PEI. These copolymers showed the phenomena of phase transitions in response to pH and temperature. The dilute copolymer solution at lower pH displayed the higher LCST. Furthermore, LCST increased with the increasing of phenylalanine grafting density. LCST of these copolymers were tunable from 7.2 to 59.6 °C by the degree of amidation and pH of solution. DLS and TEM experiments certified that the copolymer chains aggregated to form small size particles as increasing the temperature above LCST. For these reasons, the obtained smart copolymers were considered to be potential gene/drug carriers in biomedical field.     

“反公地悲剧”对生物医药研发的影响探究

目的:探究生物医药专利"反公地悲剧"的产生原因及其对生物医药产业发展的影响。方法:从分析生物医药专利滥用导致的"专利丛林"产生着手,建立了"公地"和"反公地"博弈模型,并对基础和应用研究者与专利权相关的利益冲突进行分析。结果:潜在的"反公地悲剧"影响了生物药品研发者的积极性,妨碍了生物医药产业的快速发展和技术水平的提高。结论:应从制度、研究模式、专利申请模式等方面采取相应措施,平衡专利的所有性和排他性,避免"反公地悲剧",促进生物医药产业的发展。     

固相法合成心肌兴奋肽及其类似物

用Boc-和Tos-基团分别保护氨基和侧链胍基,以1%交联度聚苯乙烯二苯甲氨基树脂为载体,用DCC固相法合成肽,HF断裂肽树脂键和去除侧链保护基团,粗产物经高效液相层析纯化,合成了心肌兴奋肽Phe-Met-Arg-Phe-NH_2及其类似物Phe-Pro-Arg-Phe-NH_2,并观察了此二种肽对大鼠血压和心率的影响。     

Recovery of phenytoin from an enteral nutrient formula

The recovery of phenytoin from phenytoin oral suspension dispersed in an enteral nutrient formula was determined. The study was conducted in two phases. In phase 1, diluted phenytoin oral suspension was added to 10 1-mL samples of full-strength Osmolite and 10 1-mL samples of a distilled water control solution to produce a theoretical concentration of 10 micrograms/mL. The samples were filtered through an ultrafiltration membrane and assayed for phenytoin concentration by a homogeneous enzyme-multiplied immunoassay technique. In phase 2, varying amounts of diluted phenytoin oral suspension were added to 30-mL quantities of half-strength Osmolite or control solution to determine the effect of phenytoin concentration on recovery of phenytoin; also, a constant amount of diluted phenytoin oral suspension was added to 30-, 60-, and 90-mL quantities of half-strength Osmolite or control solution to determine the effect of solvent volume on recovery of phenytoin. Duplicate samples of each phase 2 mixture were filtered and assayed in the same manner as phase 1 samples. The mean concentration of phenytoin in phase 1 samples was 3.70 +/- 0.28 microgram/mL for Osmolite and 9.87 +/- 0.27 microgram/mL for control solution; this difference was significant. The percentage of phenytoin recovered from phase 2 samples of Osmolite increased with increasing phenytoin concentration and decreased with increasing volumes of Osmolite. The decreased recovery of phenytoin from the enteral nutrient formula used in this study has potential clinical importance, but further research in humans is needed to substantiate these in vitro observations.     

Solubility and phase separation of benzocaine and salicylic acid in 1,4-dioxane-water mixtures at several temperatures

The solubilities of benzocaine and salicylic acid were determined in water-dioxane mixtures at several temperatures (5-40 degrees C for benzocaine and 10-40 degrees C for salicylic acid). The solubility curves as a function of dioxane ratio showed a maximum at 90% dioxane at all temperatures. Above 25 degrees C, the homogeneous mixture splits into two liquid immiscible phases. For benzocaine, the initial dioxane concentration range at which phase separation takes place increased with temperature (50-60% at 25 degrees C, 50-70% at 30-35 degrees C and 40-70% at 40 degrees C). For salicylic acid, the dioxane concentration required for phase separation (40-60% dioxane) did not change with temperature. Phase separation was not related to solid phase changes (polymorphism or solvates). The phase composition and drug extraction at the drug-rich phase were determined. The apparent enthalpies of the solution process were a nonlinear function of the dioxane ratio for both drugs. The apparent enthalpy of solution of benzocaine was larger than that expected at the upper limit of phase separation (70% dioxane), whereas for salicylic acid the apparent enthalpy of solution decreased abruptly at the region corresponding to phase separation (40-70% dioxane). Both drugs showed a nonlinear pattern of enthalpy-entropy compensation.     

Thermoresponsive Polymers with Lower Critical Solution Temperature‐ or Upper Critical Solution Temperature‐Type Phase Behaviour Do Not Induce Toxicity to Human Endothelial Cells

Thermoresponsive polymers have gained extensive attention as biomedical materials especially for targeted drug delivery systems. We have recently developed water‐soluble polypeptide‐based thermoresponsive polymers that exhibit lower critical solution temperature (LCST)‐ or upper critical solution temperature (UCST)‐type phase behaviours. In this study, the toxicity of these polymers to human umbilical vein endothelial cells (HUVECs) was investigated to assess the safety and biocompatibility. Up to 100 μg/ml, thermoresponsive polymers did not induce cytotoxicity to HUVECs, showing as unaltered mitochondrial viability assessed as cell counting kit‐8 (CCK‐8) assay and membrane integrity assessed as lactate dehydrogenase (LDH) assay. Inflammatory response, assessed as the release of chemokine‐soluble monocyte chemotactic protein 1 (sMCP‐1) and interleukin‐8 (IL‐8) as well as cytokine IL‐6, was not significantly affected by the polymers. In addition, 1 μM thapsigargin (TG), an endoplasmic reticulum (ER) stress inducer, significantly decreased mitochondrial viability, but did not affect membrane integrity or inflammatory response. The presence of thermoresponsive polymers with LCST‐type phase behaviour did not further affect the effects of TG. In conclusion, the thermoresponsive polymers used in this study are not toxic to endothelial cells and therefore could be further considered as safe materials for biomedical applications.     

USE OF PERFLUOROALKANOIC ACIDS AS VOLATILE ION PAIRING REAGENTS IN PREPARATIVE HPLC

This report describes the successful use of the ether soluble, ion pairing reagents perfluoropropionic and perfluorobutyric acid in the preparative and analytical reserved phase HPLC of underivatised peptides. The preparative separation of a l-g sample of Pyr-His-Gly, the proposed anorexigenic peptide, is described on C₁₈-silica which was packed in a flexible-walled cartridge and subjected to radial compression. The mobile phase consisted of an aqueous solution of perfluorobutyric acid (5 mM) and a flow rate of 100 ml/min was used. The purified peptide was simply isolated by neutralizing and freeze-drying the corresponding peak and then extracting the excess ion pairing reagent with ether. The product was then shown to be homogeneous by analytical HPLC and amino acid analysis. The tripeptide failed to show any effect on food intake, water intake or body weight in female rats. Similarly no effect was noted on the reproductive cycles of the rat.     

壳聚糖甲基丙烯酸酯的制备及结构研究

目的研制一种壳聚糖衍生物并探讨其应用于生物医学工程的可行性。方法将高相对分子质量的壳聚糖通过纤维素酶降解,产生平均相对分子质量在100 kD~250 kD左右的低相对分子质量壳聚糖。将甲基丙烯酸酐与壳聚糖溶液混合反应,利用红外光谱1、H核磁共振研究产物结构。向反应产物的水溶液中加入过硫酸钠和抗坏血酸以形成凝胶,通过扫描电镜观察凝胶的超显微结构。结果甲基丙烯酸连接在壳聚糖分子上,生成壳聚糖甲基丙烯酸酯。利用不同相对分子质量的壳聚糖,通过改变反应时间和反应物浓度,能够生成不同取代度的壳聚糖甲基丙烯酸酯,产物能够溶解的溶液pH值也随着取代度的不同而相应发生改变。扫描电镜的研究结果表明,壳聚糖甲基丙烯酸酯凝胶的颗粒和微孔直径都小于100 nm。此凝胶经过-20和-80℃冷冻处理后能够形成疏松多孔的结构,颗粒和微孔直径在200~500 nm。结论壳聚糖甲基丙烯酸酯可以用作纳米级生物医学材料。     

Ibuprofen quality control by electrochromatography

The quality control of drugs is generally made by HPLC. This control could be made also by capillary electrochromatography (CEC). In this paper we report the analysis by CEC of ibuprofen, a well-known anti-inflammatory non steroidic drug, and some of its impurities. The analyses were performed in a 100-microm inner diameter (I.D.) fused silica capillary, packed with RP-18 stationary phase. The mobile phase was a mixture of 100 mM formic acid solution (pH 2.5), water and acetonitrile (ACN). The ACN percentage in the mobile phase and the applied voltage were carefully studied to well resolve the drug from each impurity. The results, obtained determining ibuprofen and related compounds by CEC, showed the selectivity and efficiency of the method.