鸡肉和鸡蛋中5种利尿剂残留的超高液相色谱-串联质谱检测方法研究

为了快速高效测定鸡肉和鸡蛋中5种利尿剂(卞氟噻嗪、氯噻嗪、氯噻酮、呋塞米、氢氯噻嗪)的残留量,样品经过乙腈试剂和萃取盐提取,用Bond Elut QuEChER净化柱净化,建立了一种超高液相色谱-串联质谱法(UPLC-MS/MS)方法。结果显示:5种利尿剂在1～200 ng/mL范围内具有良好的线性相关性,相关系数均大于0.99;建立的方法检测限在0.5～1.0μg/kg,定量限在1.5～2.0μg/kg;鸡蛋和鸡肉中5种利尿剂药物在2～200.0μg/kg添加范围内平均回收率在60.8%～108.7%,批内、批间相对标准偏差的范围为0.9%～11.4%。研究表明建立的UPLC-MS/MS方法操作方便、结果准确、高效、重现性好,符合兽药残留标准检测的相关要求,可用于禽产品利尿剂残留的快速检测。     

鸡蛋和鸡肉中尼卡巴嗪残留检测高效液相色谱 串联质谱法研究

建立了鸡蛋和鸡肉中尼卡巴嗪残留标示物4,4'-二硝基碳酰替苯胺(DNC)检测的高效液相色谱-串联质谱方法(HPLC-MS/MS).液相色谱条件为色谱柱为XBridge C18柱(150 mm×2.1 mm,5 μm),流动相为甲醇 0.1 mol/L的乙酸铵水溶液(75 25,V/V),柱温30 ℃,流速0.2 mL/min,进样量20 μL.质谱条件为电喷雾离子源(ESI-),多反应监测(MRM)方式进行采集;DNC-D8同位素内标法定量.结果表明,DNC在10～500 ng/mL浓度范围内呈现良好的线性关系,R2为0.999 7;鸡蛋和鸡肉中DNC残留检测方法检测限均为0.5 ng/g,定量限均为1 ng/g;鸡蛋中从2、5和10 ng/g三个添加浓度检测结果可以看出,方法平均回收率为95.9%～102.2%,批内RSD为0.9%～4.4%,批间RSD为0.3%～2.1%.鸡肉组织从100、200和300 ng/g三个添加浓度检测结果可以看出,方法平均回收率为94.0%～103.3%,批内RSD为2.0%～6.3%,批间RSD为3.1%～5.2%.     

气相色谱-质谱法快速测定猪尿中地西泮

建立了猪尿中地西泮的气相色谱-质谱(GC/MS)检测方法.样品经C18固相萃取柱净化后进行气相色谱-质谱测定.结果表明,方法定量限为0.5 μg/L,线性范围为10～500 μg/L.在三个添加浓度2、4、6 μg/L水平上,地西泮的平均回收率为 70%～120%,批内相对标准偏差< 20%、批间相对标准偏差< 12%.     

猪肉组织中四环素类药物残留检测——高效液相色谱-串联质谱法研究

建立了猪肉组织中四环素类药物残留检测的高效液相色谱-串联质谱方法.色谱条件为色谱柱为XBridge C18柱(150 mm×2.1 mm,5 μm),流动相为0.3%甲酸乙腈溶液 0.3%甲酸水溶液;柱温 20 ℃,流速0.2 mL/min;进样量20 μL.质谱条件为电喷雾离子源(ESI );多反应监测(MRM)方式采集.外标法定量.结果表明,四环素、土霉素和金霉素在10～400 ng/mL浓度范围内呈现良好线性,相关指数R2均大于0.999;方法检测限为5 ng/g,定量限为10 ng/g.50、100和200 ng/g三个添加浓度的平均回收率为72.3%～94.6%,批内批间RSD均小于20%.     

HPLC-MS/MS快速检测动物尿液中的莱克多巴胺和克伦特罗

建立了以高效液相色谱-质谱(HPLC-MS/MS)快速检测动物尿液中的莱克多巴胺和克伦特罗分析方法.样品经SCX柱净化浓缩后,以乙腈-5 mmol/L乙酸铵(65:35,V/V)为流动相,采用Kromasil CN色谱柱分离,通过电喷雾(ESI)离子源电离多反应监测(MRM)对莱克多巴胺和克伦特罗作定性和定量分析.在1.0～500.0 μg/L的范围内线性良好(r>0.999).在0.5、4.0、40.0、80.0、200.0 μg/L添加水平下,回收率在89.7%～103.3%,相对标准偏差为2.0%～7.8%.检测限(S/N=5)为0.1 μg/L.     

高效液相色谱－串联质谱法检测猪肝组织中氯霉素残留的研究

建立了猪肝组织中氯霉素残留检测的高效液相色谱-串联质谱(LC-MS/MS)法.液相色谱条件为色谱柱为Alltech Altima C18柱(150 mm×3.2 mm,5 μm);流动相为甲醇-水(1∶ 1,V/V);柱温为30 ℃;流速为0.3 mL/min;进样量为20 μL.质谱条件为电喷雾离子源(ESI-),多反应离子监测(MRM)方式进行采集;监测离子质荷比为320.60＞52.20,320.60＞194.15.以氯霉素的同分异构体间位氯霉素作内标,内标法定量.结果表明,氯霉素的线性范围为0.5～10 ng/mL,相关系数R2＝0.999 9;方法检测限为0.1 μg/kg,定量限为0.2 μg/kg;从0.1、0.2、0.4和1.0 μg/kg四个添加浓度检测结果可以看出,方法的平均回收率为96.6%～116.6%(n＝6),批内批间RSD均小于20%.     

牛肝中氯舒隆残留检测高效液相色谱-串联质谱法研究

研究了采用固相萃取净化,高效液相色谱-串联质谱(HPLC-MS/MS)法测定牛肝中氯舒隆残留量的方法.样品用乙腈提取,HLB固相萃取小柱净化后,HPLC-MS/MS方法检测.离子源采用电喷雾负离子方式(ESI-),多反应监测(MRM)模式进行采集,外标法定量.结果表明:方法检测限为2 μg/kg,定量限为5 μg/kg.在5、20、100 μg/kg三个添加浓度范围内,方法的平均回收率为86.6%～93.5%;方法RSD≤6.8%.     

高效液相色谱法测定动物性食品中地昔尼尔残留量

本试验建立了羊肉和牛肉中地昔尼尔残留高效液相色谱方法,样品经乙腈提取,正己烷脱脂,HLB固相萃取柱净化,高效液相色谱分离,270 nm波长下紫外测定。结果表明,地昔尼尔在20～1000 μg/L浓度范围内线性良好,相关系数大于0.99;在100～1000 μg/kg的添加回收试验中,平均回收率为81.8%～93.4%,批内变异系数（n=5）小于11.9%,批间变异系数（n=3）小于9.4%。地昔尼尔在羊肉和牛肉中的检测限分别为 30.0和28.0 μg/kg,定量限分别为100.0和93.1 μg/kg,该方法简单、灵敏和准确,可用于动物性食品中地昔尼尔的残留检测分析。     

高效液相色谱法测定牛羊组织中碘醚柳胺残留量

建立高效液相色谱荧光检测法测定牛羊组织中碘醚柳胺残留量。牛羊组织中残留的碘醚柳胺,经乙腈-丙酮溶液提取,阴离子交换固相萃取柱净化,高效液相色谱-荧光法测定,外标法定量。碘醚柳胺在10～5000 ng/mL的浓度范围内呈现良好的线性关系,碘醚柳胺在牛羊肌肉、肝脏、肾脏、脂肪中的检测限均为2.5 μg/kg,定量限均为5 μg/kg,牛羊肌肉、肝脏、肾脏、脂肪中15～500 ng/g添加浓度范围内的回收率为77.4%～93.8%,批内批间RSD值均<15％。     

高效液相色谱-串联质谱法检测牛组织和奶中咪多卡残留的研究

建立了一种检测牛组织和牛奶中咪多卡残留检测的高效液相色谱-串联质谱法。牛组织(肌肉、肝脏、肾脏、脂肪)和奶在NaAc缓冲体系中酶解,经HCl溶液提取,WCX固相萃取柱净化,以0.3 %甲酸水溶液(含20mM甲酸铵)和0.3 %甲酸乙腈为流动相进行梯度洗脱,在HILIC色谱柱上分离,在电喷雾正离子(ESI+⁾模式下,用多反应监测(MRM)模式检测,同位素内标法定量。结果表明：咪多卡在2.5～1000 ng/mL的浓度范围内呈现良好线性关系,相关系数(R2⁾大于0.99;咪多卡在牛组织和奶中的检测限均为10 μg/kg,定量限均为20 μg/kg;咪多卡在牛组织和奶中20～4000 μg/kg添加浓度水平上的回收率在70.9～109%范围内;批内RSD在0.55~9.59%之间,批间RSD在2.21~12.1%之间。该方法具有灵敏度高、定量准确,重复性好等特点,可以满足牛组织和奶中咪多卡残留检测的要求。     

The prevalence of albuminuria in dogs and cats in an ICU or recovering from anesthesia

Objective – To evaluate the prevalence of albuminuria in dogs and cats admitted to the ICU or recovering from an anesthetic event. Design – Prospective clinical study over a 10‐week period in 2003. Setting – Veterinary teaching hospital. Animals – One hundred and five dogs and 22 cats. Interventions – Urine was collected from dogs and cats admitted to the ICU or recovering from an anesthetic event. When possible, a second urine sample was collected approximately 48 hours later from those animals that had albuminuria during the initial screening. Measurements and Main Results – All dog samples and most cat samples were screened for albumin using a commercial point‐of‐care immunoassay. Aliquots of samples that tested positive were stored at –20°C until subsequent albumin quantification via antigen capture ELISA. Albuminuria was detected in 63 of 105 (60.0%) dogs and in 14 of 22 (63.6%) cats; the prevalence was higher in animals admitted to ICU than in those recovering from anesthesia. In subsequent samples from 26 dogs, urine albumin decreased in 20 (76.9%) when compared with the first sample; urine albumin was undetectable in 5 (19.2%). In subsequent samples from 6 cats, 4 (66.7%) had decreases in urine albumin when compared with the first sample; 1 (16.7%) was negative for urine albumin. Eleven of 12 dogs (91.7%) and 3 of 4 cats (75%) that died within 3 days of admission to the ICU had abnormal urine albumin; whereas 52 of 93 (55.9%) and 11 of 18 (61.1%) dogs and cats, respectively, who survived more than 3 days had abnormal urine albumin. Dogs with albuminuria were at increased risk of death. Conclusions – The prevalence of albuminuria in animals admitted to the ICU or recovering from anesthesia is higher than reported previously and transient in some patients. The presence of albuminuria may be a negative prognostic indicator in this population.     

Comparison of Multistix PRO dipsticks with other biochemical assays for determining urine protein (UP), urine creatinine (UC) and UP:UC ratio in dogs and cats

BACKGROUND: Urine protein: urine creatinine (UP:UC) ratio determined from the quantitative measurement of protein and creatinine in a single urine sample is the best feasible assessment of clinically significant proteinuria in dogs and cats. A dipstick that measures urine protein, urine creatinine, and UP:UC ratio has been used in human medicine and could have application for veterinary practice. OBJECTIVE: The objective of this study was to compare the Multistix PRO dipstick (Bayer Corporation, Elkhart, IN, USA) to other biochemical methods for determination of urine protein and creatinine, and UP:UC ratio in canine and feline urine. METHODS: A complete urinalysis, including sulfosalicylic acid (SSA) precipitation, was performed on urine samples submitted to our laboratory between February and April 2003 from 100 dogs and 49 cats. Urine protein and creatinine concentrations were determined by the Multistix PRO dipstick using a Clinitek 50 analyzer (Bayer) and compared with the results of SSA precipitation and quantitative biochemical analysis. The UP:UC ratios from the dipstick results (calculated by the Clinitek 50 and also manually) were compared with those calculated from quantitative values. Pearson product-moment correlation analysis and diagnostic sensitivity and specificity (using quantitative results as the gold standard) were determined. RESULTS: For both canine and feline urine, protein and creatinine concentrations determined by the Multistix PRO correlated closely with quantitative concentrations for protein (dogs r = .78, P = .0001; cats r = .87, P = .0001) and creatinine (dogs r = .78, P = .0001; cats r = .76, P = .0001). The Multistix PRO was more sensitive and less specific than SSA precipitation for diagnosing clinically significant proteinuria. UP:UC ratios obtained by manual calculation of dipstick results correlated best with quantitative UP:UC ratios in dogs, and had higher specificity but lower sensitivity for the diagnosis of proteinuria. In cats, UP:UC ratios determined by the dipstick method did not correlate (r = -.24, P = .0974) with quantitative values. CONCLUSIONS: The Multistix PRO, with manual calculation of UP:UC, may be a good alternative for the diagnosis of clinically significant proteinuria in dogs, but not cats. Dipstick creatinine concentration should be considered as an estimate.