A validated HPLC method for the determination of donepezil in human plasma after derivatization with 9-fluorenylmethyl chloroformate

A new HPLC method has been developed for determining donepezil in human plasma. To find the optimum conditions, a derivatization reaction was performed in different media, and the reaction product was identified by NMR and GC-MS after a semi-preparative HPLC separation. Under optimized conditions, donepezil was derivatized by 9-fluorenylmethyl chloroformate in chloroform and carbonate buffer at pH 9.5 in the presence of NaI after solid-phase extraction from a plasma sample. The reaction product was quantified on a reversed-phase TRACER EXCEL ODS-A, 5 μm column using a mixture of acetonitrile–10 mM acetate buffer（pH 6.0）–THF（60：35：5, v/v/v） as the mobile phase with fluorescence detection at 264 nm（ex） and 313 nm（em）. Fluoxetine was used as the internal standard. The total run-time of the analysis was about 10 min, and a clean chromatogram was obtained. The developed method was linear over the range of 1–100 ng/mL in 500 μL of plasma samples（r20.998）. The intra-day and inter-day precision values were in the range of 2.6%–11.6%. The limit of quantification was 1 ng/mL.     

Influence of styptic fiber on clotting time in rabbits

Objective To explore the influence of styptic fiber on clotting time in rabbits so as to provide experiment data for its development.Methods Onto 0.1 mL aliquots of citrated anti-coagulant rabbit blood placed in a surfacial plate 25 ul of 0.2 mol·L-1 CaCl2 solution was dropped,and mixed well with glass stirrer;the resulting mixture was immediately capped with a piece of styptic fiber(test product group)or absorptive gelatin sponge(positive control group)of 2 cm diameter.Then,the surficial plate was rinsed with 30ml of purified water at 5,10,20,30,40 and 50 min after capping;the rinsings were allowed to stand for 1 h and were subjected to OD determination at a wavelength of 541 nm.The above procedure was repeated twice,the average value of the twice experiments was taken for evaluation of the hemostatic effect of test product.For negative control group,all procedures except for capping were same as the test product group.The haemostatic effect was judged by percent OD relative to OD at 0 min in negative control group(OD 0 min)(OD 0 min was considered as 100%);if OD value at a time was less than 80% of OD 0 min,it should be designated as primary clotting time(PCT),less than 20% as complete clotting time(CCT).Results The measured PCT was 20min for both negative and positive control groups;CCT was 50,30 and 5 min for negative control,positive control and test product groups,respectively,showing the test styptic fiber had a CCT 8 times shorter than untreated blood,10 times shorter than negative control and 6 times shorter than positive control.Conclusions The test styptic fiber has powerful hemostatic effect.     

盐酸普鲁卡因胺新的合成方法

A new route for procainamide synthesis was investigated for industrial production by direct condensation of p-aminobenzoic acid with diethylaminoethylamine in the absence of solvent and any activating or dehydrating agent. The procainamide thus obtained had a high purity and a boiling point of 240℃/2mm. The yield of the distilled base was 65% of the theory.The crude or distilled procainamide formed a hydrate containing one molecule of water, mp 51.5～52℃, from which most impurities and coloring matters could be washed away, thus greatly facilitated the purification of the hydrochloride prepared later.The hydrochloride was performed in water solution. After concentrating under dimi nished pressure at 120～140℃, the melt was poured into absolute alcohol for crystallization and decoloration. The product thus obtained agreed with the requirements of pharmacopoea and was suitable for intravenous use. The mp after recrystallizing twice from absolute alcohol was 168～170℃.     

Oxaliplatin contributes to the plasma level of total platinum in cancer patients using a HPLC-Inductively Coupled Plasma Mass Spectrometry assay

Aims： We intended to investigate the plasma level of oxaliplatin and its major dichloro product Pt （R, R-Diamine-cyclohexane） C12 using a valid HPLC-ICP-MS assay. Methods： Potential formation of products was first verified with in vitro incubation of oxaliplatin in human whole blood for～6 h and in saline for ～ 48 h. Then from three cancer patients undergoing a 2 h venous infusion of oxaliplatin at 130 mg/m2, blood samples were collected prior to and 1, 2, 2. 17, 2. 33, 2. 5, 3 and 4 h after the commencement of the infusion. Plasma samples were prepared and deproteinated instantly with cold methanol to stabilise the platinum containing species and analysed immediately. Results.. Sensitivity, accuracy and precision, recovery and stability of the method were acceptable. In saline the half-life of oxaliplatin was 8. 5 h and Pt （R, R-DACH） C12 was identified along with the parent drug. In human blood ex vivo incubation only oxaliplatin was detected with a half-life of 37.4 rain. In patients, AUC0～4h of oxaliplatin following the start of infusion accounted ～50% of that of total platinum and only the parent drug was found in deproteinated plasma at each time points. Conclusion： Oxaliplatin contributes a significant proportion to the free platinum during and 2 h after infusion in plasma of patients. No Pt （R, R-DACH） C12 was detected during the period of time. The study was supported by a research grant from Cancer Society of New Zealand.     

S-allylcysteine,a garlic derivative,suppresses proliferation and induces apoptosis in human ovarian cancer cells in vitro

Aim： To investigate the effects of S-allylcysteine （SAC）, a water-soluble garlic derivative, on human ovarian cancer cells in vitro. Methods： Human epithelial ovarian cancer cell line A2780 was tested. Cell proliferation was examined with CCK-8 and colony formation assays. Cell cycle was analyzed with flow cytometry. Cell apoptosis was studied using Hoeohst 33258 staining and Annexin V/PI staining with flow cytometry. The migration and invasion of A2780 cells were examined with transwell and wound healing assays. The expression of relevant proteins was detected with Western blot assays. Results： SAC （1-100 mmol/L） inhibited the proliferation of A2780 cells in dose- and time-dependent manners （the ICsovalue was approximately 25 mmoVL at 48 h, and less than 6.25 mmol/L at 96 h）. Furthermore, SAC dose-dependently inhibited the colony formation of A2780 cells. Treatment of A2780 cells with SAC resulted in G/S phase arrest and induced apoptosis, accompanied by decreased expression of pro-caspase-3, Parp-1 and Bcl-2, and increased expression of active caspase-3 and Bax. SAC treatment significantly reduced the migration of A2780 cells, and markedly decreased the protein expression of Wnt5a, p-AKT and c-Jun, which were the key proteins involved in proliferation and metastasis. Conclusion： SAC suppresses proliferation and induces apoptosis in A2780 ovarian cancer cells in vitro.     

15-14C标记青蒿素的合成

15-¹⁴C]Artemisinin(8) was prepared by the biosynthesis of[15-¹⁴C]dihydroartemisic acid(14) which was synthesized from diketone in 6 steps. A supernatant liquidprepared from the tender leaves of ripe Shanghai Qinghao(Artemisia annua L.)was incubated with themixture of compounds l3 and l4(100 mg, total activity 3. 26 MBq, 13:14=1:1) at 30℃ or 37℃ for 4 hr. After the addition of natural artemisinin(100 mg) ,the mixture was heated at l00℃for5min , and extracted with chloroform(method A)or petroleum ether(bp. 60～90℃, method B).Theextract was evaporated and the residue was recrystallized(method B)or purified py preparative thinlayer chromatography(methed The crude product was recrystallized from methylene chloride—Petroleum ether to yield 8 with constant specific radioactivity. The mean rate of incorporation in runs1～8was l.17%。The possible influence factors of the biotransformation were studied. The incuhation temperaturewas considered as a key factor.     

Pharmacokinetic study of repaglinide floating drug delivery system in rabbits by RP-HPLC method

The present work is aimed to study the pharmacokinetic parameters of optimized repaglinide floating drug delivery system(FDDS) by 24 factorial designs,followed by comparison with a commercially available formulation.The main effects and interactions of formulation variables were studied by using normal and pareto charts.The optimized formulation shows a fickian diffusion drug release mechanism.Pharmacokinetic parameters of the designed drug delivery system were evaluated in rabbit models.Mean while a simple,specific high performance liquid chromatographic method was developed and validated as per biopharmaceutical specifications,the linearity was observed at the range of 110-550 ng/mL(r2 = 0.999).By using methanol-phosphate buffer(pH 2.5)(70:30,v/v) as mobile phase at the flow rate of 1.0 mL/min the validation shows a better retention time of 5.2 min for repaglinide.And the same validation method was used for pharmacokinetic profile analysis of repaglinide marketed products and FDDS.The comparative pharmacokinetic results such as tmax,half-life,area under the curve,mean residence times were increased significantly for the repaglinide in FDDS than the marketed product of repaglinide except Cmax and elimination rate constant.     

气相色谱法同时检测A群脑膜炎球菌多糖疫苗中的残留乙醇和丙酮

Objective To establish a capillary gas chromatography method for simultaneous determination of the residual ethanol and acetone in biologicals, such as group A meningoeeceal polysaccharide vaccine. Methods The DB-FFAP-type column was selected as a separation column by test. The temperatures of injection port, detector and column were set at 200, 250 and 60 ℃, respectively. The injection volume was 1 μl and the split ratio was 10: 1. The flow rate of carrier gas (nitrogen) was kept at 2.0 ml/min. In the definitive chromatographic conditions, ethanol and acetone were located, and the minimum detection limits and the linear ranges of ethanol and acetone were determined. The tests of repeatability, accuracy and sample were carried out. Results In the definitive chromatographic conditions, ethanol and acetone were separated completely, the minimum detection limits of ethanol and acetone were O. 196 and 0. 102 rag/L, respectively. There was a good linearity in each solvents ( r = 0. 9997). The method had a good repeatability, and the average recovery rates of ethanol and acetone were 102.8% and 102.9%, respectively. Conclusion The method is suitable for simultaneous determination of the residual ethanol and acetone in group A meningococcal polysaceharide vaccine.     

Upregulation of S100A4 after spinal cord transection in adult rats

AIM: To investigate whether spinal cord transection induces changes of gene expression of S100A4 protein. METHODS: In a spinal cord transection model, S100A4 expression and cellular localization were examined using cDNA microarray, Northern blot, immunohistochemistry, and immunofluorescence double-labeling methods. RESULTS: There was very limited S100A4 mRNA expression in the control spinal cord. However, S100A4 mRNA expression was increased significantly in both the rostral and caudal spinal cord segments adjacent to the injury site. Specifically, S100A4 gene expression was substantially increased at d 2, peaked at d 7 and d 14, and remained high up to 28 d post-injury. During its peak expression, S100A4 protein was localized in astrocytes of the spinal cord within 5 mm from the site of spinal transection. CONCLUSION: Spinal cord transection induces prolonged S100A4 expression at both mRNA and protein levels in areas close to the injury site. Increased expression of S100A4 in astrocytes after spinal cor     

Novel rearrangement products of the degradated derivative of maoecrystal A, an ent-kaurane-type diterpene

Two novel rearrangement products of the degradated derivative of maoecrystal A (1), an ent-kaurane-type diterpene via a Wagner-Meerwein process, have been reported.     

Novel rearrangement products of the degradated derivative of maoecrystal A, an ent-kaurane-type diterpene

Two novel rearrangement products of the degradated derivative of maoecrystal A (1), an ent-kaurane-type diterpene via a Wagner-Meerwein process, have been reported.     

膜分离法回收土霉素结晶母液中的土霉素

土霉素结晶母液经超滤膜预处理后 ,通过反渗透膜所得浓缩液 ,再经超滤膜处理后 ,15 %氨水调p H值从土霉素结晶母液回收土霉素 ,得到的土霉素纯度 82 .9% ,效价 771u/ mg,回收率 6 2 %。此结晶母液为二次母液 ,与车间冲洗水等混合后可较容易地进行生物降解     

Behavior and resorption of mitomycin C following multiple intravesical administrations

Although several pharmacological data of intravesical mitomycin C (MMC) are available now, data about resorption following subsequent intravesical instillations with different instillation times are lacking. We have analyzed MMC concentrations in blood plasma and urine following eight subsequent instillations, with 0.5- and 1.0-h instillation times. The relationships between urinary pH, urinary MMC concentrations, and MMC blood plasma concentrations were determined, as well as the stability of MMC in urine at pH 5-8 at 37 degrees C. An average of 40.3 and 46.4% of the total parent drug was recovered for the 0.5- and 1.0-h instillations, respectively. Blood plasma concentrations of MMC could be measured in nearly all patients and were independent of instillation times, urine concentration, or urinary pH. Resorption of MMC and recovery was stable during eight subsequent instillations. It was demonstrated that MMC can be degradated in urine at physiological conditions (pH less than 6; 37 degrees C). However, neither an influence of prolongation of the instillation time on MMC recovery from urine, nor a significant correlation between urinary pH and urinary MMC concentrations could be demonstrated. Since MMC can be degradated at pH less than 6 within 0.5 h, buffering of instillation fluids containing MMC is recommended. Reuse of instilled MMC, therefore, cannot be advised.     

牛胰蛋白酶制备工艺的改进及其对基因工程人胰岛素前体的酶切作用

目的对牛胰蛋白酶制备工艺进行改进,制备高纯度牛胰蛋白酶,并对其酶切基因工程人胰岛素前体的作用进行考察。方法采用粗制后先色谱分离再活化的方法对传统工艺进行改进,对传统工艺制备样品和改进工艺制备样品中的胰蛋白酶和胰凝乳蛋白酶的比活力进行测定和比较;进一步采用这2种样品对基因工程人胰岛素前体进行酶切,对酶切作用进行比较。结果传统工艺制备样品中胰蛋白酶比活力为212.5 U·mg-1,胰凝乳蛋白酶比活力为20.4 U·mg-1;而改进工艺样品中胰蛋白酶比活力为240.4 U·mg-1,胰凝乳蛋白酶比活力为0.14 U·mg-1。传统工艺制备样品酶切基因工程人胰岛素前体目标产物纯度质量分数为16.3%,改进工艺制备样品酶切基因工程人胰岛素前体目标产物纯度质量分数为32.2%。结论粗制后先进行SP色谱可实现胰蛋白酶原和胰凝乳蛋白酶原较好的分离,该方法适合于高纯度胰蛋白酶的制备,制备的胰蛋白酶适合作为工具酶进行基因工程人胰岛素前体的酶切。     

Degradation of nonylphenol polyethoxylates by ultraviolet B irradiation and effects of their products on mammalian cultured cells

Nonylphenol polyethoxylates (NPEOs) are widely used as non-ionic surfactants and their biodegradation products such as 4-n-nonylphenol are stable and have been demonstrated to be cytotoxic. In the aquatic environment, these compounds are usually exposed to sunlight, and while the correlation between the biodegradation of NPEOs and changes in cytotoxicity has been reported, the relationship between the photodegradation of NPEOs and cytotoxicity has not. In this study, we investigated the degradation of NPEO by ultraviolet (UV) irradiation, especially UVB irradiation, and the effects on mammalian cell lines. NPEO with a smaller number of ethylene oxide (EO) units showed greater cytotoxicity. Although NPEO (10) completely inhibited the proliferation of the cells, NPEO (70) showed no toxicity. UVB irradiation significantly induced a shortening of the side chain, which was due to the production of ROS. The EO side chain of NPEO (10), was gradually degradated, but that of NPEO (70) was degradated near the benzene ring. Furthermore, the degradation of the benzene ring was more effective in NPEO (70) than NPEO (10). The toxicity of NPEO (10) in cultured cells decreased following UVB irradiation, whereas that of NPEO (70) was induced after UVB irradiation at 500 J/cm2 and disappeared at 1000 J/cm2. This might be due to the production of NPEO with a short side chain and 4-n-nonylphenol by the degradation of EO and due to the degradation of the benzene ring at higher doses of UVB irradiation. This study shows the significance of UV exposure to the degradation of alkylphenol polyethoxylates in the environment.     

Gaschromatography of clemastine. A study of plasma kinetics and biological effect.

A method for estimation of clemastine in human plasma has been developed. By chronic acid oxidation the drug is degradated to chlorobenzophenone, which can then be analysed by gas-liquid-chromatography using electron-capture detection. The plasma levels of clemastine after oral and i.v. administration have been studied. Using different methods for extraction of the drug from plasma a metabolic degradation of the pyrrolidine part of clemastine is demonstrated. The metabolite proposed may be biologically active. The plasma level of the drug was found to be directly related to its biologic effect, measured as inhibition of the histamine-induced flare in human skin.     

聚氧乙烯蓖麻油EL-40、吐温80于维生素D2增溶体系中稳定性的研究

胶团状态下聚氧乙烯蓖麻油EL-40(Ⅰ)与吐温80(Ⅱ)于维生素D₂(Ⅲ)增溶体系中可进水解,呈伪一级反应,受特殊酸碱催化,干pH 6附近最稳定,Ⅰ稳定性优于Ⅱ。离子强度、初浓度、一般酸碱催化诸影响因素实验表明,于pH 6 Ⅰ,Ⅱ的酯羰基与催化剂间的极性效应微弱,在实用处方添加适量强电解质原辅料、枸橼酸、磷酸二氢盐或Ⅰ,Ⅱ浓度由1%增至2%时,均不影响稳定性。增溶后位于胶团中心的Ⅲ,由于相互作用可增加Ⅰ,Ⅱ的稳定性,而位于胶团较外层的亲油基、亲水基夹层的鲸蜡醇及更外层氧乙烯链上的对羟基苯甲酸,则对Ⅰ,Ⅱ稳定性无显著影响。     

pH及不同缓冲盐对阿莫西林化学稳定性的影响

根据化学动力学的原理,采用经典法及单测点法,考察了ｐＨ对阿莫西林化学稳定性的影响,同时,对不同种类的缓冲盐对其降解作用也进行了考察．结果表明阿莫西林的最稳定（ｐＨ）ｍ为６２～７２,在醋酸盐及磷酸盐缓冲液中较稳定．     

叶绿素降解产物金属络合物的合成及其对~(60)Co辐射小鼠的放射保护作用

通过蚕沙叶绿素的降解反应，研究了焦脱镁叶绿酸ａ、二氢卟吩ｅ６单甲酯及紫红素１８等二氢卟吩衍生物的制备方法，首次设计合成了蚕沙叶绿素降解产物的钴、铜、锌金属络合物。在确认结构的基础上观察了它们对６０Ｃｏ辐射小鼠的放射治疗作用，结果发现二氢卟吩ｅ６单甲酯铜络合物（７）能显著延长实验小鼠的存活时间，增加２１ｄ后小鼠存活数量。