p-取代2-硝基-1-苯乙醇对映体在Chiralcel OD和Chiralpak AD手性柱上的色谱拆分

为建立准确评价不对称合成反应和手性催化剂的立体选择性分析方法,采用Chiralcel OD-H和Chiralpak AD-H 手性柱,研究了7种p-取代2-硝基-1-苯乙醇对映体的高效液相色谱拆分特性.详细考察了手性柱类型、流动相中醇类调节剂对这些对映体色谱拆分行为的影响.结果表明:在优化实验条件下,7种p-取代2-硝基-1-苯乙醇对映体均可达到很好的基线拆分,并且方法简便、准确,适合于不对称亨利反应合成p-取代2-硝基-1-苯乙醇化合物的对映体纯度分析.     

三（3，5-甲基苯基氨基甲酸酯）多糖手性固定相拆分芳基硒代甘油醚对映体

采用Chiralcel OD-H和Chiralpak AD-H手性柱，研究5种新近合成的外消旋双芳基硒代甘油硫醚和4种芳基硒代甘油烷氧醚对映体的高效液相色谱拆分方法．对比这两种手性固定相、异丙醇和乙醇流动相调节剂、以及样品结构对硒代甘油醚色谱拆分的影响．除样品(1c)外，其他8个外消旋硒代甘油醚样品均可达到基线拆分．     

西沙必利在新型键合手性柱上的拆分及其在血浆中的含量测定

建立一种用新型键合纤维素手性固定相拆分西沙必利对映体的高效液相色谱方法,并利用此方法测定血浆中西沙必利的含量.使用Chiralpak IC色谱柱（250 mm×4.6 mm,5μm）,流动相为正己烷-异丙醇-二乙胺（体积比80∶ 20∶0.1）,流速0.8 mL/min,检测波长273 nm,柱温25℃.取血浆200 μL,加入西沙必利标准溶液10 μL,碱化后用正庚烷-异戊醇（体积比95∶5）提取,40℃氮气吹干.结果表明：西沙必利对映体在新型键合直链纤维素衍生化合物手性固定相上能够完全分离,分离度为1.65;其血浆提取回收率达87％,线性范围为10～ 160 μg/mL,最低检测限为5 μg/mL,RSD＜4.0％.本方法可方便地实现西沙必利对映体的分离及其在血浆中的含量测定,为临床上西沙必利的血药浓度监测及药代动力学研究提供了便捷、灵敏的分析手段.     

高效液相色谱手性固定相法拆分喹禾灵对映体

采用高效液相色谱法,在直链淀粉-三(3,5-二甲基苯基氨基甲酸酯)(Sino-Chiral AD)手性柱上,对喹禾灵外消旋体进行拆分,考察流动相正己烷中,不同的醇类添加剂、醇类添加剂浓度及温度对手性分离的影响,当流动相为V正己烷∶V乙醇(95∶5)、流速为0.5mL·min-1、25℃时喹禾灵在Sino-Chiral AD柱上获得完全分离,分离度Rs达2.17.     

Anti-allergic effects of ethanol extracts from brown seaweeds

Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities. They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan, and Sargassum graminifolium turn (SG), Sargassum thunbergii (STH), and Laminaria japonica (LJ) from China. The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin, an inhibitor against hyaluronidase. Total phlorotannins contained in the crude extracts were measured as 1.71% (SG), 0.74% (STH), 0.97% (LJ), 3.30% (SC), and 5.06% (ST). The 50% inhibitory concentrations (IC₅₀) of Pakistani SC and ST were 109.5 and 21 μg/ml, respectively, lower than those of Chinese SG, STH, and LJ (134, 269, and 148 μg/ml, respectively). An antiallergic drug, disodium cromoglycate (DSCG), had an IC₅₀=39 μg/ml, and a natural inhibitor of hyaluronidase, catechin, had an IC₅₀=20 μg/ml. The IC₅₀ of ST extract was found similar to that of catechin (21 vs 20 μg/ml) and lower than that of DSCG (21 vs 39 μg/ml). This suggests that ST is a potent inhibitor of hyaluronidase, indicating a promising future development of natural antiallergic medicines or functional foods.     

固相萃取和高效液相色谱法测定鱼腥草中的黄酮

 研究了用固相萃取预分离,高效液相色谱法测定鱼腥草根和鱼腥草叶中黄酮类物质的方法.鱼腥草根和鱼腥草叶中的黄酮用80%乙醇溶液加热回流提取,提取液用Waters Sep-Pak-C₁₈固相萃取小柱预分离脱脂,以Waters Nova-Pak-C₁₈(Φ3.9 mm×150 mm,5μm)色谱柱为固定相,以0.05 mol/L磷酸二氢钾缓冲溶液和甲醇的体积比为40:60的混合液为流动相,在该色谱条件下,鱼腥草中主要的黄酮成分均达到基线分离;用紫外二极管矩阵检测器在360 nm波长处检测,并作了色谱峰纯度分辨.方法标准回收率为98%~101%,相对标准偏差为0.85%~2.2%.     

高效液相色谱法测定果酒中的糖、甘油和乙醇

 研究了高效液相色谱法测定果酒中的糖、甘油和乙醇的方法.果酒样品用Sep-Pak-C18固相微萃取小柱预分离,以WatersSugar-PakⅠ钙型阳离子交换柱为固定相,0.05g/LEDTA钙钠水溶液为流动相,示差折光仪为检测器,一次进样测定果酒样品中的蔗糖、葡萄糖、果糖、甘油和乙醇.最低检测限在微克级,相对标准偏差在0.92%～1.52%之间,标准回收率在97%～105%之间.方法用于果酒样品的测定,结果满意.     

高效液相色谱法测定盐酸利多卡因贴剂含量

文中建立了盐酸利多卡因贴剂含量的测定方法。用Waters公司XterraC₁₈柱 (5μm,3.9mm×150mm),流动相为甲醇0.05mol·L-1的碳酸氢铵水溶液(用氨水调节pH =8.5 0,体积比为50∶50) ,流速10mL·min-1。结果显示盐酸利多卡因在20～640mg·L-1范围内呈现良好的线性关系,r值为 0.9998。利多卡因回收率为99.77%,RSD为0.68%。本方法简单、灵敏、准确,可作为该制剂内在质量的控制方法。     

牛血清白蛋白手性毛细管整体柱的分离性能

以牛血清白蛋白为手性选择器,基于甲基丙烯酸酯整体柱表面所带环氧基团具有较强反应活性的特征,采用一步法将牛血清白蛋白直接键合到其表面上,制备成牛血清白蛋白手性固定相毛细管整体柱.在毛细管电色谱模式下,进行柱分离性能研究.在-5kV的分离电压、214nm紫外检测波长、5s进样时间、10mmol/L磷酸盐流动相分离条件下,成功拆分了4种对映体和手性药物华法令,分析时间均小于15min,分离度大于1.90,最大达到8.81.     

杨树嫩茎质外体中脯氨酸含量测定方法的建立

采用高效液相色谱法HPLC对微透析液进行痕量脯氨酸的检测,研究了痕量脯氨酸柱前衍生化的方法。采用苯异硫氰酸酯PITC-乙腈溶液和三乙胺-乙腈溶液对透析液中痕量脯氨酸进行衍生化后,通过环己烷萃取,得到透析液中痕量脯氨酸衍生化的最适方法,无需后续处理可直接进样,并确定了HPLC检测条件:岛津Inertsil ODS-SP色谱柱(250 mm×4.6 mm, 5 μm);柱温:31 ℃;流动相A:0.05 mol·L^-1醋酸钠溶液;流动相B:乙腈-流动相A(1:1);洗脱条件:A:B(50:50);流速:1.0 mL·min^-1;检测波长:254 nm;进样量:20 μL。脯氨酸加标回收率为95.1 ％~104.2 %。同时,对3种杨树质外体透析液中的脯氨酸进行了测量。     

Osseointegration of hollow porous titanium prostheses loaded with cancellous bone matrix in rabbits

This study aimed to observe the osseointegration of hollow porous titanium prostheses (HPTP) loaded with cancellous bone matrix (CBM) in rabbits using histological and biomechanical perspectives.Experimental samples were implanted into the lateral femoral condyles of 66 New Zealand rabbits,allocated into the following groups:non-porous prosthesis group (Group A,n=22);HPTP group (Group B,n=22);HPTP+CBM group (Group C,n=22).The rabbits were sacrificed at 3,8 and 12 weeks,postoperatively.X-ray analyses,microscopy techniques and morphological measurement software and mechanical tests were used for evaluation.At each time point,the tissues surrounding the implants were similar in all of the groups,with bony in-growth into the 2-mm round holes observed for the defects in Groups B and C.However,the internal bone formation was significantly better in Group C than in Group B at different time points (P<0.01).Biomechanically,the pull-out forces were significantly greater in Groups B and C than in Group A (P<0.01),with no difference between Groups B and C (P>0.05).These results suggest that bone can grow into the cavities of HPTP to achieve more stable locking fixation,and those osteogenic materials,such as CBM,can enhance osteogenesis to achieve better osseointegration between the implant and the host bone.     

Special IR properties of palladium nanoparticles and their aggregations in CO molecular probe infrared spectroscopy

Dispersed Pd nanoparticles (Pdn) have been synthesized by reducing H2PdCI4 with ethanol, and stabilized using poly(vinylpyrrolidone) (PVP). The Pdn is applied to the glassy carbon substrate to form a thin film, and then the potential cyclic scanning at 50 mV.s^-1 from -0.25 to 1.25 V was carried out for about 30 min to form the aggregations of Pdn (Pdn^ag). FTIR spectroscopy of both transmission and reflection modes was employed to study CO adsorption on Pdn and Pdn^ag in both solidlliquid and solidlgas interfaces. It has been revealed that CO adsorption on Pdn film yields two IRbands near 1964 and 1906 cm-1, which are assigned to IR absorption of CO bonded on asymmetric and symmetric bridge sites, respectively. In contrast to the IR properties of CO adsorbed on Pdn, only species of CO bonded on asymmetric bridge sites was determined on Pdn^ag, and the direction of the IR band near 1963 cm^-1 is completely inverted. The full width at half-maximum (FWHM) of the COB^as band near 1964 cm^-1 is measured to be 14 cm^-1 on Pdn film, while it is 24 cm^-1 on Pdn^ag film. The results of the present study demonstrated that the inverting of the IR band direction is a general phenomenon that is closely related to the interaction between nanoparticles in aggregation of Pdn.     

Investigation of the ozone formation potential for ethanol using a smog chamber

The ozone formation reactivity of ethanol has been studied using chamber experiments and model simulations. The computer simulations are based on the MCM v3.1 mechanism with chamber-dependent auxiliary reactions. Results show that the MCM mechanism can well simulate C 2 H 5 OH-NO x chamber experiments in our experimental conditions, especially on ozone formation. C 2 H 5 OH-NO x irradiations are less sensitive to relative humidity than alkane species under our experimental conditions. In order to well simulate the experiments under high relative humidity conditions, inclusion of N 2 O 5 +H 2 O=2HNO 3 in the MCM mechanism is necessary. Under C 2 H 5 OH-limited conditions, the C 2 H 5 OH/NO x ratio shows a positive effect on d(O 3 -NO)/dt and RO 2 +HO 2 . High C 2 H 5 OH/NO x ratios enhance the production of organoperoxide radical and HO 2 radical concentrations, which leads to a much quicker accumulation of ozone. By using ozone isopleths under typical scenarios conditions, the actual ozone formation ability of ethanol is predicted to be 2.3-3.5 part per billion (ppb) in normal cities, 3.5-146 ppb in cities where ethanol gas are widely used, and 0.2-3.2 ppb in remote areas. And maximum ozone formation potential from ethanol is predicted to be 4.0-5.8 ppb in normal cities, 5.8-305 ppb in cities using ethanol gas, and 0.2-3.8 ppb in remote areas.     

Development of a new method for analyzing free aluminum ions （Al3＋） in seafood using HPLC-ICP-MS

This paper presents a novel method for simultaneous online examination of free aluminum ions （Al3＋） in seafood, using solid- phase extraction and high-performance liquid chromatography online with inductively coupled plasma mass spectrometry （SPE- HPLC-ICP-MS）, without post-column reaction. The optimum conditions for chromatographic separation of Al3＋ were achieved using an IonPac CS5A analytical column with an IonPac CG5A guard column. The mobile phase consisted of 0.040 mol/L LiOH, 0.0060 mol/L 2,6-pyridinedicarboxylic acid, and 0.090 mol/L CH3COOH （pH 4.7）. The free Al3＋ ions in seafood were extracted by shaking with the mobile phase at 70℃ for 2 h. SPE was conducted using an Oasis MCX, 3cc/60 mg, 30 μm column, which was activated and equilibrated with 2 mL of methanol and 4 mL of deionized water before use. HCl （0.075 mol/L, 2 mL） was used to wash inorganic Al from the SPE column. The standard recoveries of Al3＋ were all above 89% and the relative standard deviations were all below 5%. The proposed method was successfully used for the examination of Al3＋ in seafood samples, and the results were similar to those obtained using the static equilibrium method.     

RP-HPLC同时检测 Zymomonas mobilis 代谢组分方法的研究

优化了高效液相色谱(HPLC)同时检测Zymomonas mobilis发酵液中葡萄糖、乙醇和多种代谢产物的条件和方法,分析了影响因素、回收率和重现性.试验结果表明,选择10 mmol/L pH值为2.5 KH2PO4-H3PO4溶液作为流动相、SunFireTM C18,5μm色谱柱(4.6 mm×150 mm)、二极管阵列检测器,可同时检测出葡萄糖酸、丙酮酸、乳酸、乙酸;选用2 mmol/L硫酸溶液作为流动相、IC-PakTM lon-Exclusion 50 A7μm色谱柱(7.8 mm×300 mm)、示差折光检测器,可同时检测葡萄糖、山梨醇、琥珀酸、乙酸、乙醇.Z.mobilis发酵液的回收率和重现性的结果表明,该方法测定葡萄糖、乙醇和其它产物的相对标准偏差范围为0.005%～0.018%,平均回收率为96.86%～101.99%.     

RP—HPLC测定青蒿中青蒿素的含量

采用反相高效液相色谱法，以对羟基苯甲酸乙酯为内标，测定了青蒿中青蒿素的合量。Ｓｈｉｍ－ｐａｃｋＣＬＣ－ＯＤＳ柱，甲醇－醋酸盐缓冲液（０．０１ｍｏｌ／Ｌ，ｐＨ５．８）为流动相，ＵＶ２６０ｕｍ波长处检测。实验结果平均回收率为１０２．２％，相对标准偏差为１．０７％。方法快速、简便、准确。     

Synthesis of single-walled carbon nanotubes by the vertical floating catalyst method

The vertical floating catalyst method is first used to produce single-walled carbon nanotubes (SWNTs) continuously on a large scale by a newly developed technique and pyrolysis of n-hexane. Diameter distributions, microstructure and purity of the SWNTs film, rope and web are measured by Raman spectroscopy and electron microscope. The results show that SWNTs product has a high degree of orientation, a wide distribution of diameters (0.7–2.0 nm) and high purity of >80%.     

HPLC法测定大鼠血浆中曲安奈德的含量

采用HPLC法测定大鼠血浆中曲安奈德（TA）含量,通过对线性关系、精密度、回收率、重复性及稳定性进行试验分析,找出快速有效的含量测定方法.结果表明,采用Dionex C18柱,流动相为甲醇-水（57∶43）,流速为1.0mL/min,检测波长为240nm,柱温为35℃,以曲安西龙为内标进行测定,在0.1～64.0μg/mL浓度范围内线性关系良好,日内、日间精密度RSD均低于3%,方法回收率均在90%以上.该法可用于大鼠血浆中曲安奈德含量的测定.     

超高效液相色谱紫外法检测对苯二甲酸生产废水中的芳香羧酸

建立了超高效液相色谱－紫外法（UPLC-TUV）测定对苯二甲酸生产废水中6种芳香羧酸（邻苯二甲酸、对苯二甲酸、3-羧基苯甲醛、间苯二甲酸、苯甲酸和间甲基苯甲酸）的快速分析方法。该方法使用的色谱柱为Waters Acquity BEH C18 （2.1mm×50mm,1.7μm）,以甲醇-0.2%甲酸水（体积分数）体系进行梯度洗脱,紫外检测波长为254?nm。在优化的色谱条件下,6种芳香羧酸得到基线分离,质量浓度范围为0.5～100μg/mL（其中对苯二甲酸的质量浓度范围是0.25～50μg/mL）时,线性相关系数均大于0.9998。利用该方法检测3批废水中的6种芳香羧酸,批内相对标准偏差(RSD)均小于1.5%（n＝3）。6种芳香羧酸的一组浓度加标平均回收率均在80%～110%之间,RSD均小于6%（n＝3）,表明基质干扰少,重现性好。     

N''''-(4,6-二甲氧嘧啶-2-基)-N-β-吡啶甲酰基硫脲的高效液相色谱分析

建立了N'-(4,6-二甲氧嘧啶-2-基)-N-β-吡啶甲酰基硫脲的高效液相色谱分析方法.采用ODS色谱柱,以乙腈∶水=90∶10(v∶v)为流动相,流速1 mL/min进行分离,以紫外检测器在波长224 nm下进行测定.该方法回收率在98.76%～100.18%之间,线性相关系数为0.9996,标准偏差为0.119,变异系数为0.123%.