超高效液相色谱—串联质谱法检测鸡血液样品中喹诺酮类药物残留

旨在建立鸡血液样品中多种喹诺酮类药物残留的超高效液相色谱—串联质谱方法。样品经乙腈提取,经Waters Acquity UPLC BEH C₁₈色谱柱分离,以甲醇和0.1%甲酸水溶液为流动相进行梯度洗脱,电喷雾正离子（ESI⁺）模式电离,MRM扫描模式检测。经方法学验证,该方法的线性关系、回收率、精密度均符合要求。应用超高效液相色谱—串联质谱法建立了鸡血液样品中多种喹诺酮类药物同时检测的方法,实现了动物血液样品中12种喹诺酮类药物同时定性、定量分析。     

高效液相色谱法测定齿毛芝中的碱基

采用250SS4.6-ODSZ-8/5色谱柱,体积分数20%的甲醇为流动相,紫外260nm检测,尿嘧啶,尿苷,腺嘌呤腺苷的保留时间分别为2.23min,2.97min,4.13min和6.74min,检测齿毛芝中碱基的摩尔比依次为1`.24:0.41:2.29:2.05.     

体外产气法评定反刍家畜饲草料营养价值的研究前景

阐述了体外产气法的原理、影响体外产气量的因素及其研究前景。     

RPLC法测定饲料添加剂中的B族维生素

本文提出了利用反相离子对色谱法,简单,快速,准确同时定量测定饲料添加剂中的烟酸,烟酰胺,盐酸吡哆辛,氰钴胺素,核黄素和硫胺素。样品前处理简单,六个维生素能在12min内获得满意的分离,各组份之间的分离度Rs大于1.60。各个维生素的回收率在87.0～101.0％,相对偏差为3.1～2.0％。色谱柱为LichrosorbRP-18 250×φ5mm,流动相为甲醇/水,0.25％TEA,1.25mmol/l PICB-5,3.75mmol/l PICB-7,pH3.00,紫外可变波长检测器采用MAXPL操作方式λ 1=254nm,λ_2=280nm,λ_3=354nm,流速1.1 nl/min。     

Determination of uric acid in canine serum and urine by high performance liquid chromatography

A reproducible high performance liquid chromatography (HPLC) method was developed for analysis of uric acid in canine serum and urine. The method consists of precipitating serum proteins with phosphotungstic acid prior to HPLC analysis. Urine is analyzed after dilution with buffer. Chromatography is performed on a reversed-phase C-18 column with UV detection at 292 nm. Sensitivity of the method will allow reproducible measurement of uric acid at concentrations of 0.05 mg/dl in serum and 0.1 mg/dl in urine. The HPLC method has been used to quantify hundreds of canine serum and urine samples. The method is superior to UV absorption or colorimetric methods because its lower limit of detection allows measurement of uric acid at concentrations found in canine serum and urine.     

人参提取液体外抑制IHNV作用效果研究

探究人参提取液体外抑制CCB细胞感染IHNV的能力,构建体外CCB细胞模型,运用RTCA技术和MTT法测得不同浓度人参提取液对IHNV抑制作用曲线,并从阻断病毒复制和杀灭病毒两方面讨论人参提取液作用效果。结果表明,4%人参提取液对IHNV具有明显抑制作用,能够在16 h内保护细胞不受IHNV病毒的侵染,其中2 h时对病毒灭活抑制率最高达到51.5%,1~12 h内对病毒复制有持续抑制作用。研究可为IHVN防治药物的研发提供新的思路及参考。     

Pharmacokinetics of articaine hydrochloride and its metabolite articainic acid after subcutaneous administration in red deer (Cervus elaphus)

AIM: To develop and validate a simple and sensitive method using liquid chromatography-mass spectrometry (LC-MS) for quantification of articaine, and its major metabolite articainic acid, in plasma of red deer (Cervus elaphus), and to investigate the pharmacokinetics of articaine hydrochloride and articainic acid in red deer following S/C administration of articaine hydrochloride as a complete ring block around the antler pedicle.

METHODS: The LC-MS method was validated by determining linearity, sensitivity, recovery, carry-over and repeatability. Articaine hydrochloride (40?mg/mL) was administered S/C to six healthy male red deer, at a dose of 1?mL/cm of pedicle circumference, as a complete ring block around the base of each antler. Blood samples were collected at various times over the following 12 hours. Concentrations in plasma of articaine and articainic acid were quantified using the validated LC-MS method. Pharmacokinetic parameters of articaine and articainic acid were estimated using non-compartmental analysis.

RESULTS: Calibration curves were linear for both articaine and articainic acid. The limits of quantifications for articaine and articainic acid were 5 and 10?ng/mL, respectively. Extraction recoveries were >72% for articaine and >68% for articainic acid. After S/C administration as a ring block around the base of each antler, mean maximum concentrations in plasma (C_max) of articaine were 1,013.9 (SD 510.1) ng/mL, detected at 0.17 (SD 0.00) hours, and the C_max for articainic acid was 762.6 (SD 95.4) ng/mL at 0.50 (SD 0.00) hours. The elimination half-lives of articaine hydrochloride and articainic acid were 1.12 (SD 0.17) and 0.90 (SD 0.07) hours, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE: The LC-MS method used for the quantification of articaine and its metabolite articainic acid in the plasma of red deer was simple, accurate and sensitive. Articaine hydrochloride was rapidly absorbed, hydrolysed to its inactive metabolite articainic acid, and eliminated following S/C administration as a ring block in red deer. These favourable pharmacokinetic properties suggest that articaine hydrochloride should be tested for efficacy as a local anaesthetic in red deer for removal of velvet antlers. Further studies to evaluate the safety and residues of articaine hydrochloride and articainic acid are required before articaine can be recommended for use as a local anaesthetic for this purpose.     

高效液相色谱法测定饲料中林可霉素含量

林可霉素(Lincomycin)别名为洁霉素、林肯霉素,是一种生物合成的抗菌药物,为白色结晶性粉末,无臭,味苦,可溶于水.其盐酸盐在水或甲醇中易溶,在乙醇中略溶,耐热,性质稳定.林可霉素主要用于治疗革兰氏阳性菌,特别是耐青霉素但对本品敏感的细菌所引起的各种感染,并可防治支原体引起的猪哮喘病、家禽慢性呼吸道病,治疗厌氧菌感染如鸡的坏死性肠炎及猪的弓形体病、猪血痢等.     

Antioxidant Efficacy of a Spirulina Liquid Extract on Oxidative Stress Status and Metabolic Disturbances in Subjects with Metabolic Syndrome

Lipid peroxidation is associated with the development of some pathologies, such as cardiovascular diseases. Reduction in oxidative stress by antioxidants, such as Arthrospira (formely Spirulina), helps improving this redox imbalance. The aim of the study was to evaluate the effect of the Arthrospira liquid extract “Spirulysat^®” on oxidative markers—in particular, oxidized LDL (oxLDL)/total LDL cholesterol—and isoprostanes and to investigate its impact on lipid and glucose metabolism in the metabolic syndrome subject. A controlled, randomised, double-blind design was conducted in 40 subjects aged 18 to 65 years with metabolic syndrome after a daily intake of Spirulysat^® or placebo for twelve weeks. Blood and urinary samples were collected at three visits (V1, V2, V3) in the two groups for parameters determination. Although the Spirulysat^® group showed a decrease at all visits of the oxLDL/total cholesterol ratio, there was no significant difference compared to the placebo (p = 0.36). The urinary isoprostanes concentration in the Spirulysat^® group was reduced (p = 0.014) at V3. Plasma triglycerides decreased at V3 (p = 0.003) and HDL-cholesterol increased (p = 0.031) at all visits with Spirulysat^®. In conclusion, Spirulysat^® did not change the oxidized LDL (oxLDL)/LDL ratio but decreased the urinary isoprostanes, plasma triglycerides and increased HDL cholesterol, suggesting a beneficial effect on metabolic syndrome.