沉积物中15种多环芳烃的凝胶渗透色谱-高效液相色谱法

目的建立同时测定沉积物中15种多环芳烃(PAHs)污染物的凝胶渗透色谱-高效液相色谱分析方法。方法样品中的多环芳烃通过环己烷-乙酸乙酯(1∶1,V/V)提取,凝胶渗透色谱净化,液相色谱-荧光检测器测定,外标法定量。结果通过对梯度洗脱条件、荧光激发和发射波长等条件的优化,实现了15种多环芳烃组分的完全分离和荧光高灵敏度检测,在优化后的测定条件下,15种多环芳烃在0.20μg/L~50.0μg/L时具有良好线性关系,相关系数(r)≥0.999 4,方法的检出限为0.3μg/kg~1.0μg/kg,回收率为68.8%~104.0%,相对标准偏差≤6.7%。结论该方法准确、灵敏,适用于沉积物中15种多环芳烃的同时测定。     

凝胶渗透色谱净化-超高效液相色谱串联质谱测定鱼中8种酚类内分泌干扰物的方法研究

目的建立同时测定鱼中双酚A(BPA)、双酚B(BPB)、双酚F(BPF)、双酚S(BPS)、正壬基酚(4-n-NP)、对壬基酚(4-NP)、4-正辛基酚(4-OP)和4-特辛基酚(4-t-OP)8种常见的酚类内分泌干扰物的方法。方法样本经乙酸乙酯-环己烷提取,凝胶渗透色谱(Biobead SX-3(300 mm×10 mm)凝胶色谱柱,乙酸乙酯-环己烷(1∶1)为流动相净化,超高效液相色谱串联质谱定性和定量。结果 8种酚类内分泌干扰物在0.1μg/L～40μg/L范围内线性关系良好(r0.990),检出限为0.48 ng/kg～6.4 ng/kg,平均回收率为70.2%～112.1%,RSD在4.3%～13.2%。结论凝胶渗透色谱净化-超高效液相色谱串联质谱法处理操作简单,灵敏度高,可满足分析方法学的要求,可用于鱼中8种酚类内分泌干扰物的测定。     

凝胶渗透色谱净化-高效液相色谱法测定动物源性食品中四环素类药物残留

目的:建立凝胶渗透色谱净化-高效液相色谱法同时测定动物源性食品中四环素、土霉素、金霉素药物残留的方法。方法:样品用乙腈提取,提取液经Pharmadex LH-20凝胶柱(15 mm i.d×450 mm)净化,用1%乙酸甲醇洗脱。采用Agilent TC-C18柱(4.6 mm i.d×250 mm,5μm)分离,以乙腈-0.1%三氟乙酸(18:82,v/v)洗脱,流速为1.5 ml/min,检测波长为360 nm。结果:四环素、土霉素药物在0.02~1.0 mg/L范围内,金霉素在0.04~2.0 mg/L范围内有良好的线性关系(r0.999),检测限为11~33μg/kg,平均加标回收率为51.9%~95.2%,相对标准偏差3.4%~6.7%。结论:方法快速、简单,可应用于食品中四环素类药物残留量的检测。     

QuEChERS-超高效液相色谱串联质谱法测定蜂蜜中11种喹诺酮类药物残留

目的 优化改进QuEChERS-超高效液相色谱串联质谱(UPLC-MS/MS)测定蜂蜜中11种喹诺酮类药物残留的方法。方法 样品经均质后,对比不同的提取体系和净化条件,以及基质效应的变化,优化色谱质谱条件。结果 优化改进QuEChERS-超高效液相色谱串联质谱(UPLC-MS/MS)方法,选择冰乙酸-乙腈-水体系(1∶84∶15)溶液为提取试剂,采用C18+PSA(300 mg+125 mg)混合吸附剂净化,流动相为40%甲醇-乙腈和0.1%甲酸水溶液,同时优化色谱条件,结果各目标化合物在1.0～100.0μg/L质量浓度范围内线性关系良好,相关系数r均>0.995;回收率为72.4%～107.5%,相对标准偏差(RSD)为1.9%～8.1%,11种喹诺酮类药物检出限在0.4～1.0μg/kg,定量限在1.3～3.0μg/kg。结论 该方法快速经济,准确可靠,适合大批量蜂蜜样品中喹诺酮类药物残留的快速测定。     

气相色谱-三重四极杆串联质谱法测定海产品中18种多环芳烃

目的 建立海产品中18种多环芳烃化合物(PAHs)的气相色谱-三重四极杆串联质谱(GC-MS/MS)检测方法。方法 海产品冻干粉末用环己烷-乙酸乙酯(1∶1,v/v)为溶剂快速溶剂萃取,提取液经凝胶渗透色谱法净化后,用气相色谱-串联质谱法(GC-MS/MS)测定。结果 被测物以DB-5MS毛细管柱分离、MS/MS选择反应监测模式(SRM)检测,在1.0μg/L~100μg/L范围内,相关系数>0.999,方法检出限(S/n=3)为0.074μg/kg~0.18μg/kg(干重),相对标准偏差(RSD)为1.1%~6.8%,加标回收率为71.2%~110.6%,相对标准偏差(RSD)为3.4%~13.6%(n=6)。结论 方法准确、灵敏、重复性好,满足海产品中18种PAHs检测的要求。     

复合免疫亲和柱净化-超高效液相色谱-串联质谱法测定婴幼儿谷物辅食中10种真菌毒素

目的建立复合免疫亲和柱净化-超高效液相色谱-串联质谱法测定婴幼儿谷物辅食中10种真菌毒素的方法。方法样品经乙腈-水-甲酸(80+19+1,V/V/V)提取,真菌毒素六合一免疫亲和柱净化。色谱柱采用Waters HSS T3柱(2.1 mm×100 mm,1.8μm),流动相为乙腈-0.1%甲酸溶液(ESI+),乙腈-0.1%氨水溶液(ESI-),梯度洗脱;质谱采用电喷雾离子源,多反应监测模式进行检测,同位素内标法定量。结果 10种真菌毒素在一定范围内线性关系良好(r0.99);检测限(LOD)和定量限(LOQ)分别为0.05μg/kg~15μg/kg和0.15μg/kg~45μg/kg;低、中、高3个浓度的相对回收率分别为94.6%~106.3%、95.0%~108.1%、88.9%~115.6%,精密度(RSD)分别为4.2%~11.3%、2.3%~13.7%、2.4%~9.4%。结论该方法灵敏、准确、稳定,适用于婴幼儿谷物辅食中真菌毒素多组分的测定。     

超高效液相色谱-质谱/质谱法测定黄酒中的甜蜜素

目的建立超高效液相色谱-质谱/质谱法测定黄酒中甜蜜素的分析方法。方法黄酒样品经0.1%甲酸-水溶解,超声提取,以0.1%甲酸水-乙腈为流动相,梯度洗脱,经Zobax C18色谱柱分离,采用MRM正负模式同时采集,外标法定量。结果该方法检出限为0.030 mg/kg;线性范围为10 ng/ml^1000 ng/ml,相关系数为0.999,在添加水平为0.1μg/kg、0.5μg/kg、2.5μg/kg时,回收率为95%~102%,RSD值为1.0%~4.5%(n=6)。结论该方法操作简便、准确、灵敏度高、稳定性好,可用于黄酒中甜蜜素的测定。     

超高效液相色谱-串联质谱联用法测定水中10种农药

目的建立超高效液相色谱-串联质谱法同时测定水中(饮用水和水源水)呋喃丹、灭多威、残杀威、莠去津、灭草松、2,4-滴、敌敌畏、乐果、甲基对硫磷、马拉硫磷10种农药。方法采用直接进样方式,水样经0.22μm微孔滤膜过滤,用Dikma leapsil C18(2.1mm×150mm×2.7μm)色谱柱分离,超高效液相色谱-串联质谱(UPLC/MS/MS)电喷雾电离(ESI),多反应监测(MRM)模式,以0.1%甲酸甲醇-0.1%甲酸水为流动相等度洗脱,流速0.3mL/min,检测饮用水和水源水中的10种农药,外标法定量计算结果。结果方法的线性范围为0.1~50.0μg/L,相关系数均0.9996,检出限0.01~0.05μg/L;2个水平的平均加标回收率91.2%~99.8%;相对标准偏差(RSD)均7.66%。结论该法具有操作简单、干扰少、快速、准确可靠等特点,适用于测定饮用水和水源水中多种农药,符合国家卫生标准方法建立的相关要求。     

凝胶渗透色谱净化-固相萃取-超高效液相色谱-串联质谱法检测蔬菜中氨基甲酸酯类农药残留

目的建立全自动凝胶渗透色谱-固相萃取净化-超高效液相色谱-串联质谱法(GPC-SPE-UPLCMS/MS)定量测定蔬菜中3-羟基克百威、涕灭威、克百威、丁硫克百威、涕灭威砜、涕灭威亚砜、灭多威等7种氨基甲酸酯农药残留的方法。方法样品经乙腈提取,再经GPC和氨基固相萃取柱(Carb/NH2)净化后,以乙腈-0.1%甲酸水溶液为流动相,经Agilent Poroshell 120ec-C18色谱柱分离,电喷雾串联质谱多反应监测模式(MRM)测定。结果 7种氨基甲酸酯类农药在测定的范围内线性关系良好(r≥0.999 0),方法的检出限为0.12μg/kg~0.31μg/kg(S/N=3)。在加标水平为1.0μg/L、10.0μg/L、50.0μg/L时,方法的回收率为80.3%~105.1%,相对标准偏差为1.03%~7.10%。结论该方法简化了前处理操作,分析时间短、选择性好、灵敏度高,适用于蔬菜中7种氨基甲酸酯类农药残留的检测。     

高效液相色谱法测定大气颗粒物PM2.5中16种多环芳烃

目的建立了一种高效液相色谱同时分离和测定大气颗粒物PM2.5中16种优控多环芳烃的方法。方法采用二氯甲烷超声提取,浓缩后经乙腈定容,以乙腈和水作为流动相,反相色谱法梯度淋洗分离后,由紫外检测器串联荧光检测器检测。结果 16种PAHs的分离效果较好,线性关系良好(r0.999),平均回收率为77.5%~104.0%,相对标准偏差为1.1%~6.8%,LOD为0.1μg/L~2.3μg/L,LOQ为0.3μg/L~7.5μg/L,均符合方法学的要求。在采样点采集PM2.5样品,并进行定量分析。通过使用16种PAHs毒性当量因子,计算了各自的毒性当量。结论该方法方便、可靠、灵敏度高,可满足PM2.5中多环芳烃的日常检测要求。     

PCR系统制备地高辛标记的探针检测脊髓灰质炎病毒核酸

笔者应用聚合酶链反应（PCR）合成系统，以逆转录的SabinⅠ、Ⅱ、Ⅲ型病毒cDNA为模板，在反应液中加入标记的Dig-dUTP，经扩增制备了地高辛配基标记的脊髓灰质炎病毒cDNA探针、该法比PCR扩增产物后，电泳，片段回收到标记、提纯，常需3天。结果比较PCR技术直接制备地高辛标记cDNA探针方便，快速，标记率高，用于型别鉴定比中和试验快，敏感，特异性强等优点。     

Dental Services Utilization by Women of Childbearing Age by Socioeconomic Status

For women of childbearing age, oral health not only affects their physical and psychological well-being but also that of their children. This study used the 2003–2004 Ohio Family Health Survey (N = 9,819) to examine dental need and utilization by women in Ohio. Predisposing, enabling, and need variables were examined as they effect dental health service utilization by women of childbearing age at different socioeconomic status (SES) levels. The proportion of women in the low SES group self reporting a dental need (18%) was 3 times that of the proportion of women in the higher SES group with a self reported need (6%). Results of bivariate analysis showed that having a dental visit in the past year varied significantly by SES, race, insurance status, provider density, and need. A racial disparity in dental service utilization was noted in the bivariate analysis of the middle SES group. While dental need and type of dental coverage varied by SES, both were significantly associated with utilization of dental services within all 3 SES categories in the logistic regressions. These results suggest that measures need to be implemented to meet the goal of increasing access and utilization of dental health services by low-income populations.     

Reversal by ascorbic acid of suppression by endogenous histamine of rat lymphocyte blastogenesis

Addition of concanavalin A (Con A) to a culture of spleen cells of ODS-od/od rats, which cannot synthesize ascorbic acid, increased the activity of histidine decarboxylase (HDC) in the culture, leading to accumulation of histamine (Hm) in the medium. Treatment of the culture with cimetidine, a type 2 Hm antagonist, enhanced Con A-dependent lymphocyte blastogenesis even in the absence of any exogenously added Hm. Addition of low doses of histaminase increased Con A-dependent lymphocyte transformation. At higher doses, it abrogated the reaction. At concentrations of more than 10(-10) M, exogenously added Hm suppressed the Con A-dependent uptake of [3H]thymidine by the lymphocytes, but it significantly augmented the response at 10(-14) M. The addition of ascorbic acid (10(-8)-10(-5) M) to the culture suppressed the Con A-mediated HDC induction and inhibited Hm biosynthesis. Concomitantly added ascorbic acid at the concentrations of 10(-8)-10(-4) M increased the uptake of [3H]thymidine dependent on Con A or phytohemagglutinin by the lymphocytes. These results suggest that mitogen-dependent lymphocyte blastogenesis is activated by Hm produced by the spleen cells per se. However, when culture was prolonged, high concentrations of Hm suppressed the reaction. Ascorbic acid enhances mitogen-dependent lymphocyte blastogenesis through inhibition of HDC induction, leading to attenuation of immunosuppressive Hm production by the spleen cells.