免疫亲和柱净化/柱前衍生化-高效液相色谱荧光检测法测定粮谷中的T-2毒素

建立了免疫亲和柱净化/柱前衍生化-高效液相色谱荧光检测器测定粮谷中T-2毒素含量的方法。样品经甲醇-水(体积比为80∶20)混合溶剂提取,通过免疫亲和柱(IAC)净化,以氰酸蒽(1-AN)为衍生化试剂、4-二甲基氨基吡啶(DMAP)为催化剂进行衍生,以ZORBAX Eclipse XDB-C18 柱为分离柱,乙腈-水(体积比为80∶20)为流动相进行高效液相色谱分离及荧光检测，荧光检测的激发波长为381 nm，发射波长为470 nm。T-2毒素的质量浓度为0.01~1.5 mg/L时与峰高呈良好的线性,相关系数为0.9985。在0.01~1.5 μg/g添加水平下，回收率为79.7%~94.5%,相对标准偏差小于7%；检出限（S/N＝3）为0.01 μg/g。该方法净化效果好,灵敏度高,操作简便快速。     

镝荧光探针的构建及对牛奶中四环素残留的检测

在乙醇体系中构建三元配合物的镝荧光探针,并利用盐酸四环素(TC)对镝荧光探针具有荧光猝灭作用,提出了一种检测牛奶中四环素残留的新方法。首先确定体系的激发波长为305nm,发射波长为574nm。在配比、加料顺序、时间等方面对镝荧光探针进行了条件优化,确定了镝离子(Dy3+)、磺基水杨酸(SSA)、三正辛基氧化磷(TOPO)的最佳配比为1∶2∶0.1和30min最佳检测时间。其次建立了检测盐酸四环素的线性曲线,并获得检测范围为10-6~2×10-5 mol/L。最后,利用此荧光探针对处理的牛奶样品进行加样回收检测,回收率在96.9%~104.4%。实验证明建立的方法科学可行,对盐酸四环素具有高选择性。     

柱后还原-高效液相色谱法同时测定调制乳粉中维生素K1和维生素K2

建立了一种同时检测调制乳粉中维生素K₁和维生素K₂的柱后还原-高效液相色谱-荧光检测方法。样品用水溶解，经脂肪酶酶解，2.5 mol/L氢氧化钠溶液和乙醇溶液皂化，正己烷萃取，氮吹浓缩后，用甲醇复溶。通过Xbridge C₁₈色谱柱分离，锌粉还原柱柱后还原，荧光检测器检测，激发波长为326 nm，发射波长为432 nm，外标法定量。结果表明，维生素K₁在0.0025~2.0 μg/mL、维生素K₂在0.01~2.0 μg/mL范围内线性关系良好，相关系数均大于0.999，维生素K₁和维生素K₂的检出限分别为0.07 μg/100 g和0.24 μg/100 g，定量限分别为0.2 μg/100 g和0.8 μg/100 g；方法的加标回收率为80.39%~94.39%，精密度为0.85%~3.98%。该方法灵敏度高，重复性好，结果准确，适用于调制乳粉中维生素K₁和维生素K₂的分析检测。     

高效液相色谱法测定美白面膜中7种荧光增白剂

建立了同时测定美白面膜中7种荧光增白剂的高效液相色谱-荧光检测(HPLC-FLD)法。样品经乙腈超声提取后,经Eclipse XDB-C18色谱柱分离,以甲醇-25mmol/L乙酸铵溶液为流动相,梯度洗脱,在激发波长365nm、发射波长430nm进行测定。结果表明,FWA 85和FWA 71以及其他5种荧光增白剂分别在5~35mg/L和0.025~4mg/L的浓度范围内呈良好的线性关系,线性相关系数大于0.991;方法的检出限(S/N=3)为0.00071~0.18mg/L,定量限(S/N=10)为0.12~12.24μg/g。3种不同添加水平下的样品加标平均回收率为93.62%~115.87%,相对标准偏差为0.43%~5.40%。该方法简便、灵敏、准确,可用于美白面膜中7种目标荧光增白剂的同时测定。     

水中微量苯胺类化合物的重氮化耦合荧光猝灭法测定

基于亚硝酸根-苯胺类化合物-2-萘酚重氮化-耦合反应体系对2-萘酚的荧光猝灭作用,建立了荧光猝灭法检测水中微量苯胺类化合物的新方法.方法的激发波长为353 nm,发射波长为418 nm.在所选定的实验条件下,测定苯胺、对硝基苯胺、邻硝基苯胺的线性范围分别为:0～640 μg/L,0～720 μg/L和0～740 μg/L,检出限分别为0.017 9、0.020 5、0.026 5 mg/L.方法用于环境水样中的苯胺类化合物的测定,回收率为98%～103%.     

纳米纤维固相萃取-高效液相色谱-荧光检测麻辣烫汤液中喹诺酮类药物

建立了固相萃取-高效液相色谱-荧光检测麻辣烫汤液中5种喹诺酮类抗生素的分析方法。麻辣烫汤液样品经EDTA-Mcllvaine缓冲溶液(pH 4)提取后,以HCX固相萃取小柱净化富集,用水淋洗,2%氨化甲醇洗脱。采用高效液相色谱-荧光检测器(HPLC-FLD),于激发波长280 nm,发射波长450 nm处进行检测,流动相为甲醇-水-磷酸(25∶75∶0.1,V/V,三乙胺调至pH 2.8)。麻辣烫汤液样品中氟罗沙星、诺氟沙星、沙拉沙星、环丙沙星、奥比沙星5种喹诺酮类抗生素加标回收率为72.1%~110.3%;日内相对标准偏差(RSD)为1.6%~4.3%,日间相对标准偏差为2.0%~4.3%;检出限(LOD)为1.2~5.4μg/L;定量限(LOQ)为3.9~18μg/L。本方法能够满足实际麻辣烫汤液样品的分析要求。     

HPLC荧光法快速检测食品中的NaNO2

建立了HPLC荧光检测法测定不同食品中的NaNO2。碱性条件下以乙酸锌作为蛋白质沉淀剂纯化提取NaNO2。以C8柱作为分析柱,反相C18柱作为预柱,流动相V(水)∶V(乙腈)=60∶40,荧光检测器在激发波长375 nm发射波长415 nm条件下检测,相关系数r=0.9999,方法检出限为0.01 mg/kg,回收率84.6%~103%,相对标准偏差1.0%~5.0%。方法可用于食品中NaNO2的检测。     

表面活性剂增敏荧光分光光度法测定牛奶中头孢拉定

建立了测定牛奶中头孢拉定的荧光增敏分光光度法。该方法基于头孢拉定在碱性条件下降解之后降解产物荧光强度增强,并且降解产物的荧光强度可以被表面活性剂吐温-20增敏,增敏产物的激发和发射波长分别位于340 nm和450 nm处。考察了缓冲溶液、NaOH溶液的用量、反应温度和时间、表面活性剂等因素对体系荧光强度的影响。结果表明:头孢拉定质量浓度在0.1~1.5μg/mL范围内遵循比尔定律,线性回归方程为:F=516.57ρ+34.14,相关系数R2=0.999,并探讨了其反应机理。方法应用于牛奶中头孢拉定的检测,样品的加标回收率在90.6%~104.5%之间,检出限为0.045μg/mL,相对标准偏差为1.3%。     

铽-环丙沙星稀土敏化荧光猝灭法测定叶酸

在pH=5.0的醋酸-醋酸钠缓冲溶液中,铽(与环丙沙星反应形成1∶2的稳定络合物,其最佳激发、发射波长分别为λex=330nm、λem=545nm。在该反应体系中加入适量叶酸溶液,铽(与环丙沙星络合物的激发、发射波长位置不变,但荧光强度下降。利用这一现象,建立了简单、快速、灵敏的测定叶酸的荧光分析方法。该方法保持了叶酸结构的完整性,叶酸浓度在22~880μg/L范围内符合线性关系;方法检出限为7.8μg/L。用于片剂及胶囊中叶酸含量的测定,结果满意。6次平行测定该方法回收率为93.7%~107.9%,相对标准偏差为0.38%~2.8%。     

柱前手性荧光衍生反相高效液相色谱法分离甲状腺素对映体

以R(-)-4-N,N-二甲基磺酰胺-7-(3-异氰酸吡咯烷)-2,1,3-苯并氧杂咪唑（R(-)-DBD-PyNCS）为手性荧光衍生化试剂,成功地拆分了甲状腺素对映体D,L-四碘甲状腺原氨酸（T4）和L-三碘甲状腺原氨酸(T3)。在反应温度为40 ℃、反应时间为20 min时,R(-)-DBD-PyNCS在碱性介质中可与甲状腺素对映体生成稳定的非对映体衍生物。该衍生物在以乙腈-水-醋酸(体积比为60∶40∶1)为流动相,流速为1.0 mL/min,色谱柱为Intersil-ODS-3 C18柱(150 mm×4.6 mm,5 μm)的色谱条件下得到了充分的分离。采用荧光检测器在激发波长460 nm、发射波长550 nm下检测。D,L-T4和L-T3分别在0.016～0.30 μg/μL和0.0067～0.22 μg/μL范围内,峰面积与浓度呈良好的线性关系(r＞0.999)。D,L-T4和L-T3的最低检出限分别为0.02 μg/mL和0.85 μg/mL(S/N=3)。在D-T4、L-T4、L-T3质量浓度分别为0.10 μg/μL下测得峰面积的相对标准偏差分别为3.40%,1.63%,3.30%(n=7)。该方法成功地应用于甲状腺片中T4和T3的含量测定。     

Determination of closantel residues in milk and animal tissues by HPLC with fluorescence detection and SPE with oasis MAX cartridges

A liquid chromatographic method for the determination of closantel residues in milk and tissues is developed and validated. An acetonitrile-acetone solution (80:20, v/v) is used for the extraction of closantel residues from milk and animal tissues, and the extract is purified by solid-phase extraction with Oasis MAX cartridges and a mixture of formic acid-acetonitrile (5:95, v/v) as the elution solution. A C(18) bonded silica column is used for chromatographic separation. The mobile phase consists of acetonitrile-water (85:15, v/v) containing 0.05% triethylamine at pH 2.5, adjusted with phosphoric acid with the flow-rate set at 1.0 mL/min. Using the fluorescence emission of closantel at lambda(ex) = 335 nm and lambda(ex) = 510 nm, the calibration curve is linear, with a correlation coefficient of 0.9999 over the concentration range of 10-5000 microg/kg for the tissue sample and 10-5000 microg/L for the milk sample. The detection limit (s/n = 3) is 3 microg/kg for tissue sample and 3 microg/L for milk sample. The intra- and inter-day repeatabilities are between 3.35-7.66% and 4.04-8.67%, respectively. The proposed method enables the quantitative determination of closantel residues at levels as low as 10 microg/kg in animal tissue samples and 10 microg/L in milk samples.     

高效液相色谱-荧光检测法测定罂粟籽和火锅汤料中的罂粟碱

 用所建立的高效液相色谱-荧光检测法测定了罂粟籽和火锅汤料中的罂粟碱。采用的色谱柱为RP-C18柱(250 mm×4.6 mm i.d.,5 μm);检测激发波长为285 nm,发射波长为355 nm;流动相为甲醇-0.02 mol/L乙酸铵(体积比为70∶30),流速0.8 mL/min。实验结果表明,罂粟碱的进样量为1×10-4~0.1 μg时其质量浓度与相应峰面积有良好的线性关系,最低检测限(以信噪比大于3计)达到0.02 ng。罂粟籽中罂粟碱的回收率为99.0%～100.8%。方法快速准确,简便灵敏,分离度高,能够满足有关食品中罂粟碱的检测要求。     

离子对高效液相色谱法同时测定鱼类中四种喹诺酮类药物的残留

 采用离子对高效液相色谱法同时测定了鱼类中4种喹诺酮类药物(FQS)的残留。检测条件为:采用Waters μBondapakTM C18柱,以11 mmol/L的四丁基溴化铵溶液-乙腈(体积比为94∶6)为流动相(用冰乙酸调pH为3.0,流速1.0 mL/min),柱温40 ℃;采用荧光检测器检测,激发波长280 nm,发射波长460 nm。测定结果表明,该方法对FQS的最低检测限为1 μg/kg,在6～100 μg/kg线性范围内，溶液含量与峰面积的相关系数达0.9995以上。在高、中、低3种含量水平下对所测鱼组织中4种喹诺酮类药物进行回收率测定,结果为76%～100%,相对标准偏差小于7%。该法简便、准确,灵敏度高,符合痕量测定的要求。     

Validation of a high-performance liquid chromatography method for the determination of oxytetracycline,tetracycline, chlortetracycline and doxycycline in bovine milk and muscle

High-performance liquid chromatography with diode-array detection (HPLC-DAD) was optimised and validated for the determination of tetracyclines in bovine milk and tissues. Milk and tissue samples were extracted and purified using a solid-phase extraction HLB Oasis cartridge and analysed using HPLC-DAD set at 365 nm. The analyses were carried out using the mobile phase of 0.01 M oxalic acid-acetonitrile-methanol (60:25:15, v/v/v) on a C8 column (250 x 4.6 mm I.D., 5 microm). Recoveries of tetracyclines from spiked samples at the three concentrations (0.5, 1 and 1.5) of the maximum residues limits (corresponding to 100 microg/kg for milk and the muscle) were higher than 81.1% in milk and 83.2% in muscle. The method was successfully validated for bovine milk and muscle in compliance with requirements set by draft SANCO/ 1805/ 2000 European Decision. The decision limit (CCalpha) was in the range 113.2-127.2 microg/kg and 107.7-129.9 micro/kg for all compounds in milk and muscle, respectively. The detection capability (CCbeta) was in the range 117.2-131.3 microg/kg and 114.9-133.1 microg/kg for all compounds in milk and muscle, respectively.     

固相萃取-高效液相色谱法测定人血浆中的川芎嗪

 建立了高效液相色谱测定人血浆中川芎嗪浓度的方法。色谱条件:分析柱为Luna C18(150 mm×4.6 mm i.d.,5 μ m),流动相为甲醇-乙腈-醋酸盐缓冲液(pH 5.0)(体积比为50∶8∶42),流速1.0 mL/min,柱温40 ℃,检测波长280 nm。 血浆样品预处理采用C8固相小柱萃取法。方法的线性范围为25～5000 μg/L,线性相关系数为0.9999。高、中、低浓度 的川芎嗪在标准血浆样品中的平均提取回收率为96.72％～100.90％,日内和日间相对标准偏差(RSD)小于8.64％,准确度 为99.59%~103.26%，检测限为10 μg/L。该方法的各项效能指标符合生物样品的分析要求,可用于川芎嗪制剂的人体药 代动力学研究。     

高效液相色谱法测定水产品中残留的吡喹酮

建立了一种灵敏度高、操作简单的定量分析水产品中残留的微量吡喹酮的高效液相色谱方法。样品经乙酸乙酯提取、极性硅胶柱净化后进行高效液相色谱分析,以乙腈-水(体积比为50∶50)为流动相,流速为0.9 mL/min,ZORBAX C18色谱柱分离,紫外检测波长为214 nm。在此条件下吡喹酮在0.02～20 mg/L范围内呈线性关系,相关系数为0.99998；吡喹酮的加标回收率在85%以上,检出限为10 μg/kg。     

Online trace enrichment to determine pyrethroids in river water by HPLC with column switching and photochemical induced fluorescence detection

The potential of online trace enrichment on a highly apolar short column in LC was evaluated for the determination of pyrethroids in river water. Twelve millilitres of water samples, modified with 8 mL ACN (ACN/water 40:60, v/v), were passed through 50 x 4.6 mm ID first separation column packed with 5 microm Hypersil Elite C18. Pesticides were preconcentrated in this column while the matrix background was eluted to waste. Separation of pesticides was performed on a 3.5 microm symmetric C18 column (250 x 4.6 mm ID) with an ACN step gradient as mobile phase and fluorescence detection was used after postcolumn derivatization by using UV light. The use of photochemically induced fluorescence for detection improved sensitivity and selectivity. Quantification limits ranged from 0.05 to 0.1 microg/L and pesticide recoveries at two concentration levels (0.1 and 0.5 microg/L) were between 93.1 and 118.6%, with RSD between 2.5 and 7.5% (n = 3) in river water samples. No matrix effect was detected.     

A rapid and simple high-performance liquid chromatography method for the determination of human plasma levofloxacin concentration and its application to bioequivalence studies

A high-performance liquid chromatography method with fluorescence detection (HPLC-FLD) for the determination of levofloxacin in human plasma is described. Neutralized with phosphate buffer (pH 7.0), the sample (0.1 mL) was extracted with dichlormethane (1 mL). After voltex-mixing and centrifuged at 3000g for 6 min at 4 degrees C, the upper aqueous layer was aspirated using a micro vacuum pump and the organic layer was directly transferred to a clean test tube without pipetting. The organic solvent was evaporated and the residues were reconstituted with the mobile phase. Levofloxacin and terazosin (internal standard, IS) were chromatographically separated on a C(18) column with a mobile phase containing phosphate buffer (pH 3.0, 10 mm), acetonitrile and triethylamine (76:24:0.076, v/v/v) at a flow rate of 1 mL/min. The analytes were detected using fluorescence detection at an excitation and emission wavelength of 295 and 440 nm, respectively. The linear range of the calibration curves was 0.0521-5.213 microg/mL for levofloxacin with a lower limit of quantitation (0.0521 microg/mL). The retention times of levofloxacin and terazosin were 2.5 and 3.1 min, respectively. Within- and between-run precision was less than 12 and 11%, respectively. Accuracy ranged from -6.3 to 4.5%. The recovery ranged from 86 to 89% at the concentrations of 0.0521, 0.5213 and 5.213 microg/mL. The present HPLC-FLD method is sensitive, efficient and reliable. The method described herein has been successfully used for the pharmacokinetic and bioequivalence studies of a levofloxacin formulation product after oral administration to healthy Chinese volunteers.     

Development of a simple and sensitive high-performance liquid chromatography method for determination of glucosamine in pharmaceutical formulations

A column high-performance liquid chromatography (HPLC) method was developed for the determination of glucosamine in dosage forms. Glucosamine was derivatized by addition of a solution containing orthophthaldialdehyde. The HPLC separation was achieved on a Spherimage 80 ODS2 column (250 x 4 mm id, 5 microm particle size) using an isocratic mobile phase containing phosphate buffer-methanol (90 + 10, v/v, pH 6.50) and methanol-tetrahydrofuran (97 + 3, v/v) in proportions of 85 + 15 at a flow rate of 1 mL/min, followed by fluorescence detection. The method was validated for specificity, linearity, accuracy, precision, limit of detection (LOD), and limit of quantitation (LOQ). The detector response for glucosamine HCI was linear over the concentration range of 0.1-20 microg/mL with a correlation coefficient of 0.9980. The accuracy was between 99.4 and 100.8%. The LOD and the LOQ were 0.009 and 0.027 microg/mL, respectively. The method was applied to determination of glucosamine in solid dosage forms.