离子色谱-电感耦合等离子体质谱联用测定琥珀酸亚铁片中三价铁和二价铁含量

摘 要 目的：建立测定琥珀酸亚铁片中三价铁和二价铁含量的方法。方法: 采用Dionex RFICTM保护柱(4mm×50mm),Dionex RFICM Ion PacRCS5A分析柱(4 mm×250 mm), 淋洗液：7 mmol·K^-1 吡啶二羧酸、66 mmol·K^-1氢氧化钾、5.6 mmol·K^-1硫酸二氢钾和74 mmol·K^-1甲酸的混合溶液;流速：1.5 ml·min^-1;柱温：30.0℃;进样体积：1.3 μl。结果: Fe³+在0.5～15 μg·ml^-1范围内线性良好（r=1.000 0）;Fe²+在25～200 μg·ml^-1范围内线性良好（r=1.000 0）; Fe³+的平均回收率为103.6%（RSD=2.7%, n=9）;Fe²+的平均回收率为98.3%（RSD=1.9%, n=9）。结论:该方法简便可靠,结果准确,可用于琥珀酸亚铁片的含量测定。     

HPLC测定尼美舒利颗粒中的有关物质

摘 要 目的： 建立尼美舒利颗粒有关物质的HPLC测定方法。 方法: 采用Agilent HC C₁₈（250 mm×4.6 mm,5 μm）色谱柱;流动相：乙腈 0.01 mol·L^-1磷酸二氢铵溶液（氨水调pH至7.0）（4060）;检测波长：230 nm;流速：1.0 ml·min^-1;柱温：30℃;进样量：20 μl。结果: 尼美舒利在0.10～0.30 mg·mL^-1（r=0.999 9）浓度范围内线性关系良好,各杂质峰与主峰分离度均大于2.0,检测限为0.3 ng,定量限为1.0 ng。结论:本方法专属性强,准确度高,重现性良好,可用于尼美舒利颗粒的质量控制。     

UPLC法同时测定消积化虫散中3种成分的含量

摘 要 目的：建立UPLC同时测定消积化虫散中橙皮苷、和厚朴酚、厚朴酚3种成分含量的分析方法。方法: 采用Thermo Accucore C18（150 mm×4.6 mm, 2.6 μm）,以甲醇 0.5%冰醋酸水溶液为流动相进行梯度洗脱,流速：0.7 ml·min^-1 ,柱温：30℃,检测波长：283 nm,进样量：2 μl。结果: 橙皮苷、和厚朴酚、厚朴酚分别在4.707~28.242 mg·ml^-1 (r=0.999 4)、5.085~30.510 mg·ml^-1 (r=0.999 7)、10.651~63.908 mg·ml^-1 (r=0.999 5)浓度范围内线性关系良好,平均加样回收率分别为101.2%,104.8%,99.4%,RSD分别为1.11%,1.68%,1.49%（n=6）。结论: 本试验为消积化虫散的质量评价提供了简单、有效的方法。     

离子色谱法测定口服补液盐散（Ⅲ）中总氯的含量

摘 要 目的：建立离子色谱法测定口服补液盐散（Ⅲ）中总氯的含量。方法: 采用IonPac AS 14A色谱柱（250 mm×4mm）和IonPac AG 14A保护柱（50 mm×4 mm）,以9 mmol·L^-1的碳酸钠溶液为淋洗液,等度洗脱,流速为1.0 ml·min-1,进样量25 μl;AERS 500（4 mm）抑制器,抑制电流：45 mA;以电导检测器(ECD)检测,氯离子（Cl-）的含量按峰面积以外标法计算。结果: 氯离子（Cl-）的线性范围为0.05～20.00 mg·L^-1（r=0.999 9）;回收率为98.89%（RSD=0.56%,n=6）。结论: 本方法灵敏度高,前处理简单,准确可靠,可用于口服补液盐散（Ⅲ）中总氯的含量测定。     

离子色谱法测定枸橼酸氢钾钠颗粒中多种成分的含量

摘 要 目的：建立离子色谱法测定枸橼酸氢钾钠颗粒中钠、钾和枸橼酸含量的方法。方法: 钾和钠的色谱条件：采用Dionex IonPac CS12A色谱柱（250 mm×4.6 mm,5 μm）,流动相为0.02 mol·L^-1甲烷磺酸溶液,流速为1.0 ml·min^-1,抑制器为CSRS 300,抑制电流为59 mA,采用抑制型电导检测器,进样量为25 μl。枸橼酸的色谱条件：采用Dionex HPICE AS1离子排斥色谱柱（250 mm×9.0 mm,7.5 μm）,流动相为0.015 mol·L^-1硫酸溶液,流速为0.6 ml·min^-1,检测波长为220 nm,进样量为10 μl。结果: 钠的线性范围为0.82～82.49 μg·ml^-1（r=0.999 9）,平均回收率为98.9%,RSD为0.55% （n=9）;钾的线性范围为1.38～137.89 μg·ml^-1（r=1.000 0）,平均回收率为100.5%,RSD为0.53%（n=9）;枸橼酸的线性范围为0.021～10.600 mg·ml^-1（r=1.000 0）,平均回收率为99.1%,RSD为0.54%（n=9）。结论:本方法简便、快速、准确,可用于枸橼酸氢钾钠颗粒的质量控制。     

HPLC法测定小儿咳喘灵口服液中山梨酸钾的含量

摘 要 目的：建立HPLC法测定小儿咳喘灵口服液中防腐剂山梨酸钾的含量。方法: 采用Phenomenex Gemini C18（250 mm×4.6 mm,5 μm）色谱柱,以0.02 mol·L^-1磷酸二氢钠溶液（用磷酸调pH至4.0） 乙腈（80∶20）为流动相,流速为1.0 ml·min^-1,检测波长为262 nm,柱温为30℃,进样体积为20 μl。结果:山梨酸钾浓度在8.584～85.840 μg · mL^-1范围内与峰面积呈良好线性关系(r=0.999 9),平均回收率为100.0%,RSD为0.47%（n=9）,山梨酸钾检测限为0.43 ng,定量限为1.29 ng。结论:经过方法学验证,本法可用于小儿咳喘灵口服液中防腐剂山梨酸钾的含量测定。     

HPLC法测定追风舒筋活血片中马钱子碱、士的宁的含量

摘 要 目的： 建立追风舒筋活血片中马钱子碱、士的宁的含量测定方法。方法: 应用高效液相色谱法测定,色谱柱为Agilent SB C₁₈柱(250 mm×4.6 mm,5 μm),以乙腈 0.01 mol·L^-1庚烷磺酸钠与0.02 mol·L^-1磷酸二氢钾等量混合溶液（用10%磷酸调节pH至2.8）（21∶79）为流动相,检测波长为260 nm,流速为1.0 ml·min^-1,柱温为35℃,进样量为10 μl。结果: 马钱子碱和士的宁的线性范围分别为0. 011 0~0.219 6 mg·ml^-1 (r=0.999 4)、0.010 1~0.202 8 mg·ml^-1 (r=0.999 7);平均加样回收率分别为98.24%(RSD=1.54%)、97.92%(RSD=1.49%)(n=6) 。结论:该方法简便易行、准确、重复性好,可用于追风舒筋活血片的质量控制。     

HPLC梯度洗脱法测定葡萄糖酸依诺沙星注射液的有关物质

摘 要 目的： 建立梯度洗脱的HPLC法测定葡萄糖酸依诺沙星注射液中有关物质。方法: 色谱柱：Diamonsil^TM C₁₈(250 mm×4.6 mm,5 μm);流动相A：0.025 mol·L^-1磷酸溶液（三乙胺调pH3.0）甲醇-乙腈（80∶10∶10）,流动相B：0.025 mol·L^-1磷酸溶液（三乙胺调节pH3.0）-甲醇-乙腈（350∶325∶325）,梯度洗脱;流速：1.1 ml·min^-1;检测波长：269 nm、284 nm;进样量：20 μl;柱温：40℃。结果:在该色谱条件下,供试品稳定性及分离度良好。5-羟甲基糠醛在19.80 ng·ml^-1～19.80 μg·ml^-1范围内与峰面积呈良好的线性关系(r=0.999 9),检出限为0.18 ng,平均回收率为99.68%,RSD为0.12%(n=9)。结论: 本法结果准确、灵敏度高、专属性强、重复性好,可用于葡萄糖酸依诺沙星注射液有关物质的检测。     

HPLC法同时测定儿泻停颗粒中甘草苷和甘草酸的含量

摘 要 目的：建立测定儿泻停颗粒中甘草苷和甘草酸含量的HPLC法。方法: 采用TechMate C18 ST色谱柱（250 mm×4.6 mm,5 μm）,流动相以乙腈为A相,0.05%磷酸水溶液为B相,梯度洗脱,流速：1.0 ml·min^-1,检测波长：237 nm,柱温：室温,进样量：5 μl。结果: 甘草苷在10.32～51.62 mg·L^-1,甘草酸铵在79.40～397.00 mg·L^-1范围内与峰面积呈良好的线性关系(r>0.999)。两种成分的平均回收率分别为98.10%（RSD=1.0%,n=6）和97.15%（RSD=1.8%,n=6）。结论:该方法结果准确,重复性和稳定性好,可用于儿泻停颗粒的质量控制。     

手性流动相添加剂法测定苯磺酸左旋氨氯地平片的含量及其右旋杂质

摘 要 目的： 用磺丁基醚-β-环糊精（SBE-β-CD）为手性选择剂,建立测定苯磺酸左旋氨氯地平片的含量及其右旋杂质的高效液相色谱法。方法: 采用Agilent Eclipse XDB C₁₈色谱柱(250 mm×4.6 mm,5 μm) , 流动相为含0.02 mol·L^-1 SBE-β-CD的0.01 mol·L^-1磷酸二氢钾溶液-甲醇（60∶40）, 流速0.8 ml·min^-1, 检测波长360 nm, 柱温30℃ ,进样量10 μl。结果: 苯磺酸左旋氨氯地平在5.0～251.0 μg·ml^-1范围内线性关系良好(r=0.999 7) , 平均回收率为100.31%(RSD=0.9%,n=9),检测限为16 ng,苯磺酸左旋氨氯地平与其右旋杂质分离度良好。结论: 本方法简便、快速、准确, 专属性好, 可用于测定苯磺酸左旋氨氯地平片的含量及其右旋杂质。     

雌二醇在人、比格犬和大鼠的肝微粒体中体外代谢比较研究

采用体外肝微粒体孵育体系, 研究雌二醇在大鼠、比格犬和人肝微粒体中酶代谢动力学及代谢产物差异。通过对雌二醇浓度、肝微粒体蛋白含量和孵育时间等条件的考察, 优化雌二醇与肝微粒体的反应体系; 应用LC-MS/MS定量检测孵育体系中的雌二醇及代谢产物, 分析比较雌二醇在3个种属、不同性别肝微粒体中代谢产物种类和生成量的差异, 计算并比较相应的动力学参数。在3个种属肝微粒体中均发现9个I相代谢产物, 且百分比有种属差异。结果表明, 3个种属的肝微粒体对雌二醇I相代谢途径基本相同, 但是代谢产物的生成量及雌二醇的药物代谢动力学性质存在一定的差异。     

PAMPA–Excipient Classification Gradient Map

The effect of excipients on the artificial membrane permeability (Double-Sink PAMPA) properties of eight sparingly soluble drugs was studied. Quantities of excipient were selected to match the concentrations expected in the gastrointestinal fluid under clinically relevant conditions. Over 1,200 measurements were performed. To correct for the effects of the aqueous boundary layer and determine the intrinsic permeability, precisely measured ionization constants were used. The intrinsic permeability of weak acids was enhanced (up to 100 fold) but that of weak bases depressed (up to 270 fold) by the excipients: mefenamic acid > glybenclamide > progesterone > griseofulvin > clotrimazole > astemizole > dipyridamole > butacaine. Excipient enhancement ranked: 3 mM NaTC > 0.24% PEG400 > 0.2 M KCl > 0.24% NMP > 5% PEG400 > 0.24% PG > 1% PEG400 > 0.1M KCl > 1% PG > 1% NMP > 5% PG > 0.24% HP-β-CD > 1% HP-β-CD > 15 mM NaTC. The study clearly indicates that the method is suitable for use in preclinical development to assess the effect of excipients on the permeability of sparingly soluble drug candidates. The method is quick, cost-effective, and reasonably accurate. The self-rank-ordered PAMPA-Mapping may be a helpful visualization tool for delivery screening.Contribution number 21 in the PAMPA—a Drug Absorption in vitro Model series from pION. (14) is part 17 in the series. Double-Sink™, Gut-Box™, and PAMPA-Mapping™ are trademarks of pION INC.     

Milking and partial characterization of venom from the Brazilian spider Vitalius dubius (Theraphosidae)

The theraphosid spider genus Vitalius contains several species found in southeastern Brazil. In this work, we used electrostimulation to obtain venom from Vitalius dubius and examined its general composition. Male spiders yielded significantly less (p < 0.05) venom (12.5 ± 0.7 mg of liquid/spider, n = 16; mean ± S.E.M.) than female spiders (25.5 ± 2.0 mg of liquid/spider, n = 11). However, when corrected for spider weight, males yielded slightly more venom (2.89 ± 0.16 mg/g vs. 2.45 ± 0.76 mg/g for males and females, respectively, p < 0.05). Venom yield correlated linearly with spider weight for spiders weighing up to ∼12-13 g, but decreased in very heavy females. There was a marked decrease in venom yield after the first milking. The protein concentration of pooled venom was 18.3 ± 2.4 mg/ml (n = 4) and accounted for 16.6 ± 4.7% of the dry venom weight. The venom contained high hyaluronidase activity (275 ± 24 TRU/mg of protein, n = 4), with a molecular mass of ∼45 kDa estimated by zymography. SDS-PAGE revealed a few proteins with molecular masses >14 kDa but showed two staining bands of peptides <14 kDa. The venom reacted in ELISA with affinity-purified IgG from commercial arachnidic antivenom. Immunoblotting with this IgG detected proteins of 30-140 kDa only. Fractionation of the venom by reverse-phase chromatography resulted in five major and eight minor peaks.     

An Investigation of the Differential Effects of Ursane Triterpenoids from Centella asiatica,and Their Semisynthetic Analogues,on GABAA Receptors

The ursane triterpenoids, asiatic acid 1 and madecassic acid 2 , are the major pharmacological constituents of Centella asiatica, commonly known as Gotu Kola, which is used traditionally for the treatment of anxiety and for the improvement of cognition and memory. Using the two‐electrode voltage‐clamp technique, these triterpenes, and some semisynthetic derivatives, were found to exhibit selective negative modulation of different subtypes of the GABA_A receptor expressed in Xenopus laevis oocytes. Despite differing by only one hydroxyl group, asiatic acid 1 was found to be a negative modulator of the GABA‐induced current at α₁β₂γ_2L, α₂β₂γ_2L and α₅β₃γ_2L GABA_A receptors, while madecassic acid 2 was not. Asiatic acid 1 exhibited the greatest effect at α₁β₂γ_2L (IC₅₀ 37.05 μm ), followed by α₅β₃γ_2L (IC₅₀ 64.05 μm ) then α₂β₂γ_2L (IC₅₀ 427.2 μm ) receptors. Conversion of the carboxylic acid group of asiatic acid 1 to a carboxamide group (2α,3β,23‐trihydroxy‐urs‐12‐en‐28‐amide 5 ) resulted in enhanced inhibition at both the α₁β₂γ_2L (IC₅₀ 14.07 μm ) and α₂β₂γ_2L receptor subtypes (IC₅₀ 28.41 μm ). The results of this study, and the involvement of α₅‐containing GABA_A receptors in cognition and memory, suggest that asiatic acid 1 may be a lead compound for the enhancement of cognition and memory.     

Signalling pathways in bradykinin- and nitric oxide-induced hypotension in the normotensive rat; role of K+-channels

1. Bradykinin and nitric oxide (NO) are potent hypotensive agents. In the present study, the role of K⁺-channels in the signalling pathways responsible for their hypotensive action was investigated in normotensive, anaesthetized rats. The rats were treated with ion-channel inhibitors before administration of bradykinin (2.8, 5.6, 28 and 56 nmol kg⁻¹, i.v.) followed in some of the protocols by nitroprusside (1.1, 3.5, 7, 14, and 28 nmol kg⁻¹, i.v.).
2. No attenuation of the hypotensive response to bradykinin was detected for inhibitors of the Na-K-Cl-cotransporter (30 μmol kg⁻¹ furosemide), the ATP-sensitive K⁺-channel (40 μmol kg⁻¹ glibenclamide), high conductance Ca²⁺-activated K⁺-channel (180 μmol kg⁻¹ tetraethylammonium, 54 μmol kg⁻¹ tetrabutylammonium, 35 nmol kg⁻¹ iberiotoxin, 35 nmol kg⁻¹ charybdotoxin) or the low conductance Ca²⁺-activated K⁺-channel (74 nmol kg⁻¹ apamin).
3. However, the voltage-sensitive K⁺-channel (I_A) inhibitor 4-aminopyridine (4.05–40.5 μmol kg⁻¹) induced a concentration-dependent (P<0.0001) attenuation of the hypotensive response (P<0.0001). Bradykinin had no effect on heart rate in anaesthetized rats and this observation was not altered by pretreatment with 4-aminopyridine.
4. 4-Aminopyridine (53 μmol kg⁻¹) also significantly attenuated the hypotensive response to nitroprusside (P<0.0003) without altering the heart rate concentration-response curve. Of the two Ca²⁺-activated K⁺-channel inhibitors tested on nitroprusside-induced hypotension, tetrabutylammonium induced a slight attenuation (P<0.0101), whereas iberiotoxin had no effect.
5. We therefore concluded that, although the acute hypotensive response to bradykinin in the normotensive rat is not mediated through nitric oxide synthesis, the hypotensive response to both agents was mediated through opening of voltage-sensitive K⁺-channels (I_A), resulting in a decrease in peripheral vascular resistance.

     

Dietary intake of organophosphorus pesticide residues through vegetables from Kumasi, Ghana

Contamination and health risk hazards of organophosphorus pesticides residues in vegetables were studied. Ethyl-chlorpyrifos, observed at an average level of 0.211 ± 0.010 mg kg⁻¹ in 42% of tomato, 0.096 ± 0.035 mg kg⁻¹ in 10% of eggplant and 0.021 ± 0.013 mg kg⁻¹ in 16% of pepper was below the 0.5 mg kg⁻¹ MRL. Dichlorvos was the most frequently detected residue in all the samples analyzed. Levels of malathion in tomatoes (0.120 ± 0.101 mg kg⁻¹) and pepper (0.143 ± 0.042 mg kg⁻¹) exceeded the MRL of 0.1 mg kg⁻¹. Health risks were found to be associated with methyl-chlorpyrifos, ethyl-chlorpyrifos, and omethioate in tomatoes and methyl-chlorpyrifos, ethyl-chlorpyrifos, dichlorvos, monocrotophos and omethioate in eggplant. Routine monitoring of these pollutants in food items is required to prevent, control and reduce the pollution and to minimize health risks.     

Characterization of action potential-triggered [Ca2+]i transients in single smooth muscle cells of guinea-pig ileum

1. To characterize increases in cytosolic free Ca²⁺ concentration ([Ca²⁺]_i) associated with discharge of action potentials, membrane potential and [Ca²⁺]_i were simultaneously recorded from single smooth muscle cells of guinea-pig ileum by use of a combination of nystatin-perforated patch clamp and fura-2 fluorimetry techniques.
2. A single action potential in response to a depolarizing current pulse elicited a transient rise in [Ca²⁺]_i. When the duration of the current pulse was prolonged, action potentials were repeatedly discharged during the early period of the pulse duration with a progressive decrease in overshoot potential, upstroke rate and repolarization rate. However, such action potentials could each trigger [Ca²⁺]_i transients with an almost constant amplitude.
3. Nicardipine (1 μM) and La³⁺ (10 μM), blockers of voltage-dependent Ca²⁺ channels (VDCCs), abolished both the action potential discharge and the [Ca²⁺]_i transient.
4. Charybdotoxin (ChTX, 300 nM) and tetraethylammonium (TEA, 2 mM), blockers of large conductance Ca²⁺-activated K⁺ channels, decreased the rate of repolarization of action potentials but increased the amplitude of [Ca²⁺]_i transients.
5. Thapsigargin (1 μM), an inhibitor of SR Ca²⁺-ATPase, slowed the falling phase and somewhat increased the amplitude, of action potential-triggered [Ca²⁺]_i transients without affecting action potentials. In addition, in voltage-clamped cells, the drug had little effect on the voltage step-evoked Ca²⁺ current but exerted a similar effect on its concomitant rise in [Ca²⁺]_i to that on the action potential-triggered [Ca²⁺]_i transient.
6. Similar action potential-triggered [Ca²⁺]_i transients were induced by brief exposures to high-K⁺ solution. They were not decreased, but rather increased, after depletion of intracellular Ca²⁺ stores by a combination of ryanodine (30 μM) and caffeine (10 mM) through an open-lock of Ca²⁺-induced Ca²⁺ release (CICR)-related channels.
7. The results show that action potentials, discharged repeatedly during the early period of a long membrane depolarization, undergo a progressive change in configuration but can each trigger a constant rise in [Ca²⁺]_i. Intracellular Ca²⁺ stores have a role, especially in accelerating the falling phase of the action potential-triggered [Ca²⁺]_i transients by replenishing cytosolic Ca²⁺. No evidence was provided for the involvement of CICR in the action potential-triggered [Ca²⁺]_i transient.

     

Stability of Lidocaine in Aqueous Solution: Effect of Temperature,pH, Buffer,and Metal Ions on Amide Hydrolysis

The degradation of lidocaine in aqueous solution obeys the expression k _obs = (k _H+[H ⁺] + k _o ) [H⁺]/([H ⁺ ] + K _a + k_o K _a([H ⁺ ] + K _a) where k _H+ is the rate constant for hydronium ion catalysis, and k _o and k_o are the rate constants for the spontaneous (or water-catalyzed) reactions of protonated and free-base lidocaine. At 80°C, the rate constants for these processes are 1.31 × 10^–7 M ^–l sec^–1, 1.37 × 10^–9 sec^–1, and 7.02 × 10^–9sec^–1; the corresponding activation energies are 30.5, 33.8, and 26.3 kcal mol^–1, respectively. It was found that the room temperature pH of maximum stability is 3–6 and that lidocaine is more reactive in the presence of metal ions such as Fe²⁺ and Cu²⁺. The dissociation constant, K _a, for lidocaine at 25–80°C was also measured at 0.1 M ionic strength and a plot of pK _a versus 1/T gave a slope of (1.88 ± 0.05) × 10³ K^–1 and intercept 1.56 ± 0.16.     

New flavonol glycosides from leaves ofSymplocarpus renifolius

A study was carried out to evaluate flavonol glycosides in leaves ofSymplocarpus renifolius (Araceae). From the water fraction of the MeOH extract, three new flavonol glycosides were isolated along with three known compounds, kaempferol-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-7-O-β-D-glucopyranoside, quercetin-3-O-β-D-glucopyranosy-l-(1→2)-β-D-glucopyranoside, and caffeic acid. The structures of the new flavonol glycosides were elucidated by chemical and spectral analyses as quercetin-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-7-O-β-D-glucopyranoside, isorhamnetin-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-7-O-β-D-glucopyranoside, and quercetin-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-7-O-(6^IIII-trans-caffeoyl)-β-D-glucopyranoside.     

Lignan glycosides from the leaves of <Emphasis Type="Italic">Osmanthus heterophyllus</Emphasis>

Seven known lignan glycosides were isolated from the leaves of Osmanthus heterophyllus: (+)-syringaresinol 4-O-β-d-glucopyranoside, (+)-syringaresinol 4, 4′-O-di-β-d-glucopyranoside, (+)-medioresinol 4, 4′-O-di-β-d-glucopyranoside, (+)-medioresinol 4-O-β-d-glucopyranoside, (+)-pinoresinol 4, 4′-O-β-d-glucopyranoside, (+)-epipinoresinol 4-O-β-d-glucopyranoside and phillyrin. Their structures were determined on the basis of spectral data.