高效液相色谱-串联质谱法同时测定鸡肉中氯霉素类药物 及其代谢物残留方法的建立

建立了鸡肌肉中氯霉素、甲砜霉素、氟苯尼考及氟苯尼考胺残留检测的液相色谱-串联质谱(LC-MS/MS)分析方法。样品在碱性条件下用乙酸乙酯提取后,再用正己烷去除脂肪,MCX小柱净化,洗脱液经浓缩,0.22μm滤膜过滤后,用高效液相色谱-串联质谱测定。采用电喷雾电离正负离子切换,多反应监测(MRM)模式测定。4种药物在2～100 ng·mL-1的系列浓度范围内均呈良好线性关系,相关系数r均大于0.990。样品中氯霉素的检测限为0.1μg.kg-1,定量限为0.3μg.kg-1;氟苯尼考的检测限为0.2μg.kg-1,定量限为0.5μg.kg-1;甲砜霉素和氟苯尼考胺的检测限为1.0μg.kg-1,定量限为3.0μg.kg-1。4种药物在0.2～2.0μg.kg-1的添加浓度范围内,平均回收率为79.3%～97.3%,相对标准偏差(RSD)均小于20%。满足了鸡肉中氯霉素、甲砜霉素和氟苯尼考残留的确证分析,同时对其主要代谢产物氟苯尼考胺进行了痕量监测。     

饲料中磺胺氯吡嗪钠含量的高效液相色谱检测方法的建立

为建立饲料中磺胺氯吡嗪钠的高效液相色谱检测方法,饲料经乙腈提取,旋转蒸发浓缩,2 mL甲醇+8 mL 0.05mol.L-1KH2PO4溶解,固相萃取净化,0.2μm有机相滤器过滤后,回收液经Agilent 1100液相色谱仪进行检测。检测条件:在C18色谱柱上,流速为1.000 mL.min-1,柱温25℃,紫外检测波长为272 nm,流动相为乙腈和0.2%磷酸混合液(体积比为35∶65)。试验结果显示:磺胺氯吡嗪钠的色谱峰保留时间为7.5 min;在添加0.5、1和2μg.mL-1条件下,回收率为90.6%～97.1%;检测限为0.5 mg.kg-1,定量限为1.0 mg.kg-1,线性范围为0.50～10.00μg.mL-1,回归方程为Y=57.332X+2.972 9(R2=0.999 3);4种饲料样本的相对标准偏差(RSD)为1.0%～2.9%。结论:本试验所建立的高效液相色谱检测方法灵敏度高、准确性和重现性好,可以对饲料中的磺胺氯吡嗪钠进行定量检测。     

气相色谱法在食品及饲料有害物质分析中的应用

气相色谱法、气相色谱-质谱联用法、毛细管柱气相色谱-质谱联用法等方法提高了检测的效率与灵敏度,检测结果基本能达到国际标准,为食品及饲料中有害物质的分析提供了技术条件,有利于卫生部门对饲料及食品安全进行质量监督.文章论述了气相色谱法在食品及饲料中有害物质检测中的应用.     

饲料中三聚氰胺的ELISA检测方法的探讨

试验利用BRAXIS试剂盒和自制（经气相色谱质谱法确证不含三聚氰胺）三聚氰胺添加量为2 mg/kg的配合料和浓缩料作为阳性对照样品,对100批次饲料产品的进行了三聚氰胺筛选,并将两种方法的筛选结果按照NY/T1372-2007中的气相色谱质谱法进行了确证和比较。试验结果表明：利用三聚氰胺添加量为2 mg/kg配合料和浓缩料为阳性对照样品,对样品的筛选结果,要比使用BRAXIS试剂盒的内制曲线筛选的结果,产生的假阳性少,准确率相对要高。     

Application of Current Hapten in the Production of Broad Specificity Antibodies Against Organophosphorus Pesticides

Diethylphosphono acetic acid （DPA） was used as a current hapten to generate broad specificity polycolonal antibodies against a group of organophosphorus pesticides. Six New Zealand white rabbits were immunized with immunogens synthesized by the active ester method （AEM） or 1-ethyl-3-（3-dimethylaminopropyl）-carbodimide method （EDC）. The titers of antisera reached 25 600 by AEM and 6 400 by EDC, respectively. Polyclonal antibodies raised against DPA were screened and selected for the competitive indirect enzyme-linked immunosorbent assay （CI-ELISA）. A CI-ELISA for DPA was developed with a detection limit of 3.536 ng mL^-1and an I50 value of 0.182 μg mL^-1. The assay specificity was evaluated by obtaining competitive curves for several structurally related compounds as competitors. The antiserum showed high affinities to chlorpyrifos, diazinon, omethoate, parathion-ethyl and profenofos with I50 of 0.12, 0.15, 0.21, 0.88, 0.97 and 2.5 μg mL^-1, respectively. The results indicate that the assay could be a screening tool for quantitation and semiquantitation determination of the above former five organophosphorus pesticides.     

气相色谱-质谱法检测食品中甲氰菊酯的残留量

建立了检测10种食品中甲氰菊酯残留量的气相色谱-质谱方法。样品采用正己烷、乙腈或乙酸乙酯提取,液液分配及固相萃取柱净化,净化液由气相色谱-质谱测定,外标法定量。本方法的回收率为70.0%～110.0%,相对标准偏差为3.3%～12.3%,检测低限为0.01 mg/kg。     

Multi-Residue Determination of Eight Anabolic Steroids by GC-MS in Muscle Tissues from Pigs

A gas chromatography-mass spectrometry （GC-MS） method to determine eight anabolic steroids （diethylstilbestrol, methyltestosterone, norethindrone, 17α-ethynylestradiol, estradiol, 6α-methyl-17α-hydroxy-progesterone, estradiol benzoate, and chlormadinone acetate） was developed. Muscle samples were extracted with liquid-liquid extraction and clean-up was performed in two steps, the extracts obtained were derivatized with heptafluorbutyric （HBF） anhydride and analyzed by GC-MS. In the above method, the linear scope was 2.5-50 μg kg^-1. The range of the recoveries was 78.5-148% for diethylstilbestrol, 70.8-109% for methyltestosterone, 69.8-87.2% for norethindrone, 67.7-120% for 17α-ethynylestradiol, 82.8-103% for estradiol, 70.3-99.2% for 6α-methyl-17α-hydroxy-progesterone, 73.0-104% for estradiol benzoate, and 72.9- 91.8% for chlormadinone acetate. The range of the coefficients of variation within batches was 0.4-12%; the range of the coefficients of variation between batches was 6.4-11%. The limit of detections and the detection capability were 0.99 and 3.30 μg kg^-1 for diethylstilbestrol, 1.05 and 3.50 μg kg^-1 for methyltestosterone, 1.19 and 3.97 μg kg^-1 for norethindrone, 0.94 and 3.13 μg kg^-1 for 17α-ethynylestradiol, 1.45 and 4.83 μg kg^-1 for estradiol, 1.56 and 5.20 μg kg^-1 for 6α-methyl-17α- hydroxy-progesterone, 1.92 and 6.40 μg kg^-1 for estradiol benzoate, and 2.41 and 8.03 μg kg^-1 for chlormadinone acetate, respectively. These results showed that the method was widely available, accurate, and sensitive.     

Pharmacokinetics of Milbemycin Oxime in Dogs Following Its Intravenous and Oral Administration

The pharmacokinetics of milbemycin oxime was investigated in dogs following oral(per os, PO) and intravenous(IV) administration. Three groups of dogs received milbemycin oxime tablets as a single PO dose equal to 0.25, 0.5 and 1.0 mg · kg-1 of milbemycin oxime, respectively, another group received a single IV dose of 0.5 mg · kg-1. Blood samples were collected at predetermined times after drug administration and the milbemycin oxime concentrations in plasma were determined by LC-MS/MS. The drug protein binding in dog plasma in vitro was determined by equilibrium dialysis at concentrations spanning the range of values observed in vivo in dog plasma. After PO administration at doses of 0.25, 0.5 and 1.0 mg · kg-1, milbemycin oxime was slowly absorbed and eliminated, the time to reach the maximum plasma concentration(Tmax) was 4.14±0.20, 4.27±0.14 and 4.06±0.13 h, the mean absorption time(MAT) was 19.06, 13.67 and 11.77 h, the terminal rate half-life(t1/2λz) was 15.06±0.37, 11.09±0.54 and 9.76±0.89 h and the total body clearance(Cl) was 1.15±0.05, 1.18±0.03 and 1.17±0.07 m L · min-1 · kg-1, respectively. The maximum plasma concentration(Cmax, 36.50±1.40, 76.11±2.77 and 182.05±7.20 ng · m L-1, respectively) and the area under the first-moment curve(AUC-10→∞, 985.83±49.46, 1 663.12±51.42 and 3 558.04±197.88 mg · h · L, respectively) increased accordingly to the administered dose rates; the oral bioavailabilities were estimated to be 88.61%, 74.75% and 79.96%, respectively. The values of fu were 0.12%, 0.14% and 0.13% in dog plasma, respectively. In conclusion, the pharmacokinetics of milbemycin oxime in dogs following oral administration revealed its higher oral bioavailability and advantageous pharmacokinetic properties, such as its lower total body clearance and longer elimination half-life, and indicated that the single oral dose of 0.50 mg · kg-1 of milbemycin oxime which was recommended in all the parasitological efficacy studies allowed an adequate concentration of the drug.     

超声萃取/气相色谱法测定麝香中的麝香酮含量

利用气相色谱法-氢火焰离子化检测器（GC/FID）快速测定麝香中麝香酮含量。样品经乙醇-超声波提取、过滤后,直接利用GC/FID测定,外标法定量。实验测定麝香酮回收率大于95%;定量限为0.80μg.mL-1;校准曲线线性范围为0-320μg.mL-1,线性相关系数r为0.9995;三次高、中、低浓度（50、150、300μg.mL-1）测定峰面积RSD%分别为1.08、0.89、0.55。本实验表明,乙醇超声波提取-GC/FID测定麝香中的麝香酮含量是一种简单、快速、准确的方法。     

日粮中添加不同剂量大豆黄酮对小尾寒羊血清中 SOD和MDA的影响

试验选取来源相同、体重约20kg的健康3月龄雄性小尾寒羊5只,试验采用前后自身对照,研究日粮中添加不同剂量的大豆黄酮对血清中SOD和MDA的影响。试验分3系列进行,每系列试验进行2周。第1系列为对照期,第2系列为低剂量期(按3mg.kg-1饲料添加),第3系列为高剂量期(按6mg.kg-1饲料添加)。结果显示:血清中SOD水平对照期为27.54±11.38U.mL-1,低剂量期为37.41±12.09U.mL-1,高剂量期为41.14±13.80U.mL-1。低剂量期较对照期差异显著(P<0.05),高剂量期较低剂量期差异不显著(P>0.05)。血清中MDA水平对照期为8.99±1.56nmol.mL-1,低剂量期为7.12±2.74nmol.mL-1,高剂量期为6.21±1.04nmol.mL-1。低剂量期较对照期差异显著(P<0.05),高剂量期较低剂量期差异不显著(P>0.05)。结果提示,两种剂量比较大豆黄酮在日粮中按3mg.kg-1饲料添加可以达到提高机体抗氧化水平。     

喹乙醇和分子氨对鲤幼鱼血清SOD和MDA的影响

文章采用双因子多水平试验设计,研究喹乙醇和分子氨同时作用对鲤血清SOD和MDA的影响。喹乙醇在饲料中的添加水平为0,200,500,1500 mg.kg-1,水体中分子氨浓度为0.069,0.137,0.411 mg.L-1。结果显示,试验组鲤血清SOD活性在214.386～551.137 U.mL-1之间,较对照组(631.374 U.mL-1)显著降低(P<0.05);MDA含量在2.427～5.572 nmol.L-1之间,较对照组(1.756 nmol.L-1)显著升高(P<0.05)。多重比较显示,喹乙醇添加量达到500 mg.kg-1、分子氨浓度达到0.137 mg.L-1时,SOD活性的下降并趋于稳定;当喹乙醇和分子氨浓度达到1 500 mg.kg-1,0.411 mg.L-1时,MDA含量显著上升(P<0.05)。喹乙醇与分子氨的交互作用显著。试验结果表明,分子氨和喹乙醇可直接影响鲤幼鱼体内的脂质过氧化水平,且这种氧化损伤的程度与二者浓度密切相关。     

Effects of Fructooligosaccharides,compared with Direct—Fed Microbial Bacteria,and Zinc Bacitracin on Cecal Microbial Populations and Performance of Broilers

1　Introduction　　 Currently,the consumers made higher and higher demands on quality of food and beganto pay attention to methods and ways of animal production for ensuring food safety andhuman health Antibiotics have been used in animal feeding as growth promoters for longhistory.In recent years,this has increasingly become a focus of heated debate.Much attentionhas been received for their negative effects on animal and human being as well.On one hand,the positive influence of feeding growt…     

高效液相色谱—串联质谱法测定鸡粪中癸氧喹酯的残留量

采用高效液相色谱—串联质谱法测定鸡粪中癸氧喹酯的残留量.样品经乙腈提取、HLB固相萃取小柱净化,采用ESI+电离模式和多反应监测模式(MRM),以内标法进行定量.结果表明:该法的线性范围为1-200 ng.mL-1,r2大于0.99;选取5、10、100μg.kg-1 3个含量进行空白鸡粪添加癸氧喹酯的回收率试验,回收率为84.4%-100.1%,批内、批间RSD均小于15%,方法检出限为2.5μg.kg-1,定量限为5.0μg.kg-1.可见,高效液相色谱—串联质谱法简单快速、灵敏度高、选择性强,适用于鸡粪中癸氧喹酯药物残留量的确证检测.     

原子荧光光谱法测定农药中砷和汞的方法研究

农药中的砷、汞是使农产品产生毒性的重要原因,为探究农药中砷和汞同时检测的方法,通过原子荧光光谱对农药中砷和汞进行测定,讨论了不同前处理方法对测定结果的影响,最终确定了王水消解样品-原子荧光光谱法同时测定砷和汞的方法,该方法对砷和汞的回收率分别为90.1%~104.0%和89.5%~96.2%,检出限为0.14和0.003 1ng·mL-1,RSD为4.9%和5.2%,当砷的质量浓度处于0~100.0ng·mL-1,汞的质量浓度处于0~2.0ng·mL-1时,标准曲线均能呈良好的线性关系,相关系数分别为1.000和0.999 8,结果满意。     

植酸酶鼠源多克隆抗血清的制备

 【目的】制备灵敏性高、特异性强的植酸酶多克隆抗体。【方法】将初步纯化的麸皮植酸酶蛋白经凝胶电泳鉴定纯度后,按50 μg蛋白/只?次免疫Balb/C小鼠,共免疫4次,每次间隔4周,最后一次免疫60 d后,摘眼球取血,制备抗血清。利用间接ELISA方法测定抗血清效价,间接竞争ELISA测定敏感性和特异性。【结果】凝胶电泳的麸皮植酸酶只有一个条带;血清植酸酶抗体效价达1×104;半数抑制浓度达148.87 ng?mL-1。此抗血清对市售的普通微生物植酸酶、市售包被微生物植酸酶及浓缩的微生物植酸酶的半数抑制浓度分别达到165.59 、163.80和166.51 ng?mL-1,交叉反应率分别为89.85%、90.88%和89.41%。100℃煮沸5 min后的麸皮、市售普通微生物植酸酶、市售包被微生物植酸酶及浓缩酶半数抑制浓度分别为2 871.34、5 208.85、7 914.12和5 804.24 ng?mL-1,交叉反应率分别为5.18%、2.86%、1.88%及2.56%。【结论】制备出了具有高效价、高灵敏度和特异性的鼠源植酸酶多克隆抗体,为植酸酶单克隆抗体制备及植酸酶ELISA检测试剂盒研制奠定了基础。     

桔梗中脂肪酸成分的GC-MS分析

[目的]分析测定桔梗中的脂肪酸成分。[方法]采用索氏提取法提取桔梗科植物桔梗中的脂溶性成分,经甲酯化处理后用气相色谱-质谱联用技术（GC-MS）分离和鉴定,运用面积归一化法确定各成分的相对百分含量。[结果]从桔梗脂肪油中分离鉴定出34种脂肪酸,其中不饱和脂肪酸15种,主要种类有亚油酸（42.79%）、棕榈油酸（0.30%）、11-二十碳烯酸（1.53%）、亚麻酸（14.02%）等;饱和脂肪酸19种,主要种类有棕榈酸（13.71%）、硬脂酸（1.36%）、花生酸（0.79%）、山愈酸（1.78%）、木蜡酸（1.38%）、二十六烷酸（3.14%）、二十八烷酸（3.51%）等。[结论]桔梗的营养价值较高,具有很好的开发利用前景。     

五叶地锦种子中脂肪酸成分的GC-MS分析

[目的]分析测定五叶地锦种子中的脂肪酸成分。[方法]采用索氏提取法提取五叶地锦种子中的脂溶性成分,经甲酯化处理后用气相色谱-质谱联用技术（GC-MS）分离和鉴定,运用面积归一化法确定各个成分的相对百分含量。[结果]从五叶地锦种子脂肪油中鉴定出11种脂肪酸,其中不饱和脂肪酸6种,主要有：亚油酸（87.14%）、棕榈油酸（0.05%）、8,11-二十碳烯酸（0.12%）、11-二十碳烯酸（0.22%）等;饱和脂肪酸5种,主要有：棕榈酸（8.13%）、硬脂酸（2.60%）、花生酸（0.09%）、十七烷酸（0.09%）等。[结论]五叶地锦种子的营养价值较高,具有很好的开发利用价值。     

紫海胆黄脂肪酸的气相色谱-质谱分析

为了了解紫海胆黄中脂肪酸的组成,采用Bligh-Dyer提取法对样品中脂肪油进行提取,甲酯化后利用气相色谱-质谱联用仪进行分析测定。结果发现,从紫海胆黄中共鉴定出14种脂肪酸,饱和脂肪酸6种,相对百分含量占总检出量的32.89%;不饱和脂肪酸8种,相对百分含量占总检出量的67.11%,其中,5,8,11,14,17-二十碳五烯酸(EPA)和4,7,10,13,16,19-二十二碳六烯酸(DHA)的相对百分含量分别为12.73%和1.21%。     

西华段沙颍河和贾鲁河表层水体中有机氯农药研究

采用固相萃取-气相色谱/质谱联用分析水体中有机氯农药的方法,分析了淮河(河南段)沙颍河和贾鲁河表层水体中有机氯农药的分布及组成特征。结果表明,研究区14个采样点中共检出包括六六六、滴滴涕、七氯、环氧七氯、反式九氯、艾氏剂、硫丹硫酸酯和甲氧滴滴涕在内的共13种有机氯农药,其总含量范围在97.41～496.16 ng/L,其中以六六六(HCHs)和滴滴涕(DDTs)为主,各类有机氯农药均未超出国家地表水环境质量标准。研究区的有机氯农药污染除主要源于历史上农田中有机氯农药的残留外,也有近期新农药污染源进入水环境的可能。     

铜、维生素A及互作效应对肉仔鸡肠壁组织结构、肠道微生物和血清生长激素的影响

 【目的】研究日粮中添加铜和维生素A及互作效应对肉仔鸡小肠各段肠壁厚度和绒毛高度、盲肠主要微生物、血清生长激素（GH）的影响。【方法】采用4×2(Cu×VA)完全随机试验设计,日粮Cu水平为0、8、150、225 mg?kg-1,VA水平为1 500、5 000 IU?kg-1,生长阶段分为前期（0～4 w）和后期（4～7 w）。选用1 d艾维茵肉仔鸡448只,随机分为8组,每组4个重复,每重复14只鸡,公母比为1﹕1。【结果】①前期添加Cu（8 mg?kg-1）生产性能较好,后期不添加Cu生产性能较好。②添加Cu 225 mg?kg-1明显降低生长前期肉仔鸡回肠肠壁厚度,添加Cu 150 mg?kg-1使生长后期肉仔鸡小肠各段肠壁厚度明显较低,在整个生长期,高铜对绒毛高度无影响;日粮添加Cu 150 mg?kg-1显著提高盲肠乳酸杆菌和双歧杆菌数量,降低大肠杆菌数量,添加Cu 225 mg?kg-1显著降低盲肠乳酸杆菌和双歧杆菌数量,增加大肠杆菌数量;Cu 8 mg?kg-1组盲肠沙门氏菌数量最低。③日粮中添加VA5 000 IU?kg-1显著降低前期小肠各段肠壁厚度和后期空肠肠壁厚度、提高前期十二指肠绒毛高度;显著增加盲肠大肠杆菌、乳酸杆菌、前期沙门氏菌和双歧杆菌的数量;④Cu和VA交互作用显著影响前期回肠肠壁厚度、后期空肠肠壁厚度(P＜0.05);极显著影响前期十二指肠绒毛高度、后期十二指肠和回肠绒毛高度、前后期盲肠内乳酸杆菌、双歧杆菌、大肠杆菌和沙门氏菌数量(P＜0.01);⑤Cu、VA及互作对血清GH无影响(P＞0.05),前期GH平均水平高于后期。【结论】日粮添加Cu 150 mg?kg-1和VA 5 000 IU?kg-1有益于肉仔鸡小肠肠道形态和盲肠肠道菌群平衡;Cu和VA存在互作效应。