多糖-药物轭合物的研究与展望

多糖类物质作为赋形剂在药物制剂中已被广泛使用,多糖结构中包含了多种活性基团如羟基、羧基、氨基等,具有良好的亲水性、生物可降解性以及生物安全性,使其在聚合物-药物轭合物的构建中成为理想的载体材料.目前天然的多糖大分子及其衍生物作为药物载体的研究方兴未艾,以多糖为载体的聚合物-药物轭合物在定位或靶向给药、组织工程、生物黏附等领域也备受关注.本文以天然多糖-药物轭合物的研究现状为切入点,总结归纳了多糖-药物轭合物的设计与构建途径,介绍了其在药物传递中的应用,讨论并分析了多糖在轭合物体系中的角色和发挥的作用,对以多糖为载体的聚合物-药物轭合物发展的方向予以了讨论.     

深圳市宝安区蔬菜农药残留研究

根据2006年、2007年和2008年对55种蔬菜、共27551份样品农药残留的检测结果,分析了广东深圳市宝安地区蔬菜农药残留的状况和规律.结果表明:随着政府各项监督管理措施的落实,宝安地区蔬菜农药残留超标率逐年下降,2006年为4.35%,2007年为4.34%,2008年为1.41%;每年6～8月超标率最低,而冬春两季超标率较高;检出超标率最高的农药是有机磷类农药,包括甲基异柳磷、治螟磷、毒死蜱和敌敌畏,其次是氯氰菊酯和甲氰菊酯等拟除虫菊酯类农药;在抽检的55种蔬菜中超标率较高的是几种十字花科蔬菜,依次是芥菜、小白菜和菜心.     

荔枝农药残留的初步调查

本文对广东省一些荔枝园进行抽样调查,结果初步显示按常规方式生产的荔枝有三氯杀螨醇、氯氰菊酯以及甲胺磷农药残留,而经权威认证机构认证的有机荔枝园生产的有机荔枝未检测出农药残留.有机荔枝的出现解决了食品安全问题,是未来荔枝市场发展的必然趋势.     

福州市蔬菜农药残留检测与分析

采用农业行业标准NY/T761-2008检测方法,用气相色谱仪对福州市3家超市和3家农贸市场销售的16个蔬菜品种共60份样品进行有机氯及拟除虫菊酯类农药残留的检测,并根据GB2763 - 2005标准判定检出超标情况.结果表明:农药残留检出率为31.67％;农药残留超标率为3.33％.从蔬菜种类上,白菜类、瓜类的检出率...     

蔬菜中农药残留检测技术研究进展

对目前蔬菜中农药残留分析检测方法及其前处理过程以及快速检测技术作了综述。固相萃取(SPE)、超临界流体萃取(SFE)等新的萃取方法已逐渐代替了液-液萃取(LLE)等传统提取方法。色谱技术是农药残留分析中的重要手段。毛细管气相色谱(CGC)、高效液相色谱(HPLC)及其联用技术是现阶段农药残留分析中的主要检测方法。并指出了今后该领域的研究方向。     

环境介质中有机磷农药残留检测方法的研究与进展

在我国农业生产中,有机磷农药大量用于果蔬中,成为广谱、高效的病虫害防治手段.然而,由于有机磷农药长期不合理及过量使用,造成农作物、土壤和水等环境介质中出现有机磷农药或是其代谢物的残留,对消费者的健康产生极大威胁,农药残留问题已成为威胁食品安全的重大隐患.开发检测环境介质中有机磷农药残留的高灵敏和高准确性的方法具有极其重...     

有机磷农药对人类健康的影响及农药残留检测方法研究进展

随着工农业生产的发展, 社会与生态环境环境对人类健康的影响愈来愈大。环境污染严重影响人类身体和心理健康。对有机磷农药的生产及使用现状, 有机磷农药的结构和毒性作用, 有机磷农药残留对生态环境的污染和对人类健康的危害以及检测方法进行了探讨, 以期为有机磷农药的安全使用和农药残留检测提供参考依据。     

套袋对荔枝果实质量和农药残留的影响

用不同颜色和不同开口方式果袋对纪子笑荔枝进行套袋处理,对比研究了套袋对果实质量和农药残留的影响．结果表明,套袋对增进果实着色有明显效果,套袋果实Ⅰ、Ⅱ级果率在57．81％～81,57％之间,而对照仅为38．63％．套袋后果实的单果重量显著升高,尤其是白色袋的增重效果更为明显．虽然同种颜色的封口袋增重效果优于开口袋;但袋色对果实增重的影响作用远远大于套袋方式,开口袋不利于防虫,封口袋对防治荔枝虫害有一定效果,但防病效果不明显．套袋对果实营养成分的影响不显著,对果实品质无不利影响,但不利于农药的消解,可导致果实中甲氰菊酯和敌百虫残留量的增加,套袋果园配套农药品种的选择有待进一步筛选。     

农药残留预测模型可靠性的检验与改良

对农药残留预测模型可靠性问题进行了分析。根据矩阵的条件数理论,提供了检验预测模型可靠性的方法,基于岭回归和广义岭回归估计理论,建立了对不可靠预测模型改良的方法。最后通过氰戊菊酯在甘篮上的残留动态预测,对所建改良方法进行了检验,结果表明,预测模型的精度得到了大幅度提高.     

果蔬中有机氯农药残留的分析测定

目的:用高效气相色谱法对蔬菜和水果中的有机氯农药残留进行测定分析.方法:称取一定量的样品,采用丙酮和乙酸乙脂(4:1)提取,旋转蒸发仪上蒸发近干,石油醚和乙酸乙脂(4:1)洗脱过柱净化,再用旋转蒸发仪蒸发近干,5ml石油醚定容,在高效气相色谱仪上进行色谱分析.结果:样品采用匀浆提取法,测定选择BPX608石英毛细管柱,柱温225℃,样品的回收率在92%-105%之间.结论:该法具有简便、快捷、准确的特点,为进一步改进测定方法提供依据.     

农药污染与鸟禽类农药中毒

农药曾经为人类控制生物病虫害作出过巨大贡献,但农药污染也破坏了生态环境,对野生乌类的生存造成了严重威脸。文章从农药的种类、对环境污染的特征、鸟类农药呈母亲同理、临床中中毒症状和治疗等方面进行论述,呼呈人类应当限制农药的生产和作用,应该为保护乌类、保护生态环境而努力。     

农药残留检测关键用酶固定化研究进展

为保障消费者食用安全,迫切需要研发农产品和食品中的农药残留快速检测技术.酶抑制法检测是目前农药残留快速检测技术中的主要研究方向之一,而酶的固定化是用基于酶抑制法原理对农药残留检测研究中的重要步骤.通过物理或化学的方法高效地将酶固定于载体上,同时保持酶的催化活性是开发各类基于酶抑制法检测农药残留传感器的关键.本文将从固定...     

Pesticide Residues in Agricultural Produce in Hubei Province,PR China

Pesticide residues in agricultural produce were examined in two villages of Qianjiang municipality, Hubei province, PR China. Six food groups were sampled from the fields prior to harvesting from the farmers' market and from farmers' homes. Organochlorine residues were detected in almost all examined food groups, with residue levels significantly lower than the national tolerances (MRL). Total BHC residues were on average 31.7?µg/kg and DDT 102.5 (µg/kg. Organophosphorus residues were detected in vegetable samples. Mean residue levels of phoxim and methamidophos in vegetables were 89.9?µg/kg and 36.5?µg/kg, respectively, both exceeding the MRL. Estimated daily intakes (EDIs) of pesticide residues per person, based on the six food groups sampled, were 4.88?mg for total DDT, 2.04 (µg for total BHC, and 19.33 (µg for methamidophos. The overall results show that the increased use and misuse of pesticides for crop protection in Qianjiang municipality, notably in vegetable production, have led to worrisome levels of pesticide contamination of agricultural produce that may carry certain risks for human health.     

Health Hazard Assessment of Pyridaben Residues in Egyptian Strawberries

Dissipation behavior and hazard assessment of the insecticide/acaricide pyridaben applied to strawberries were investigated under the climatic conditions of Egypt. A validated gas chromatographic method (GC-μECD) was used to determine pyridaben residues when applied at the recommended rate and twice this rate. The average recoveries were in the range between 95.8% and 103% with associated relative standard deviation not exceeding 14.5%. The estimated limit of quantification for pyridaben was 0.005 mg/kg. The field results showed that pyridaben dissipated rapidly in strawberries and had a half-life of approximately 2.3 days. The hazard assessment was evaluated by using the hazard quotient (HQ). The results showed that the HQ value was significantly less than HQ = 1. This result implied that the hazard of pyridaben use in strawberries even at double the recommended dosage was negligible to human. This study could provide guidance for the safe and reasonable use of pyridaben in strawberries and to prevent health problems to consumers; however, further hazard assessment studies are needed to ascertain the hazard of pyridaben residues on strawberries to vulnerable groups, including children, pregnant women, and elderly consumers.     

Bound morphine and codeine in the capsule of Papaver somniferum

The polysaccharide fraction of the capsule of Papaver somniferum contained bound morphine and codeine. The alkaloids appear to be bound to the polymer by two different types of linkage.     

Monitoring and Risk Assessment of Pesticide Residues in Tea Samples from China

In the present study an effort was made to monitor the residue levels of 32 pesticides in tea samples collected from three representative tea districts of China during 2010 to 2012. A total of 223 samples of green tea, pu-erh tea, black tea, and oolong tea were determined using gas chromatography with mass spectrometry (GC-MS). Among 223 samples, 198 samples contained pesticide residues, and 39 samples had residue levels that were more than the European Union (EU) maximum residue limits (MRLs). The most positive and violated MLRs were observed in Oolong tea. The highest detection rates and the most often exceeding the MRLs were observed for the residues of bifenthrin. Ten pesticides were not found in the 223 tea samples. The potential health risks to consumers due to tea consumption in three representative cities were estimated. The results suggested that non-cancer hazards of organophosphorus, organochlorines, and pyrethroids and the cancer risks from exposure to hexachlorobenzene, heptachlor, chlordane, and pp’-DDT were clearly below the safe limit. Nevertheless, an investigation into continuous monitoring and tighter regulation of pesticide residues in tea samples are almost always desirable or even necessary for public health protection.     

A Rapid Determination of 30 Prohibited Pesticide Residues in Lycii Fructus by UPLC-MS/MS

Prohibited pesticide residues have become one of the main factors affecting the quality and safety of Lycii Fructus, However, rarely studies focus on the rapid determination of these residues. Here, a total of 30 kinds of prohibited pesticide residues were determined by ultra-performance liquid chromatography tandem triple quadrupole mass spectrometry (UPLC-MS/MS) in five different process ways. Pretreatment methods, chromatographic separation and detection conditions in mass spectrometry were all optimized accordingly. Among the five different pretreatment methods, the first and third solid phase extraction failed to provide high recoveries of sulfosulfuron compounds (both lower than 60%). Recovery of chlorphenamidine by the Quick Easy Cheap Effective Rugged and Safe multiresidue method (QuEChERS) was lower than 60%, which did not meet the requirements of trace determination. The concentrations of 30 prohibited pesticides residues treated by straightforward and solid phase extraction showed good linearity in their corresponding ranges, with correlation coefficients over 0.99. The average recoveries of straightforward ranged from 78.13% to 110.9%, while RSD ranged from 1.3% to 16.9%, albeit poor purification was observed. The recovery yield from solid phase extraction was between 67.75% and 103.08% with RSD value from 0.8% to 14.0%, which met the requirements of trace determination, this method has good precision and stability. These results could be employed to other Traditional Chinese Medicines (TCMs) in detecting prohibited pesticide residues.     

菜籽油中乐果农药残留表面增强拉曼光谱研究

本文以内壁吸附银纳米粒子的毛细玻璃管作为活性基底,以市售的乐果农药作为试验样品,用表面增强拉曼光谱技术在中性和酸性条件下对菜籽油中乐果农药残留进行检测。在中性条件下只能检测乐果农药浓度到200 mg/kg,而在酸性条件下可以检测乐果农药浓度到0. 1 mg/kg,已接近食品中最大农药残留量0. 05 mg/kg的国家安全标准。试验结果表明,在酸性条件下表面增强拉曼光谱可以作为检测菜籽油中乐果农药残留的一种有效方法。     

食品中农药残留的新型生物检测技术研究进展

食品安全是关系国计民生的重大战略问题。农药残留（简称农残）是造成食品质量与安全问题的重要因素。食品中农药残留不仅发生率高,而且超标严重,涉及范围广,长期接触或食用含有农药残留的食品会危害人体健康。传统的农残分析技术已经很难满足多样化食品安全检测的实际需求,现代新型生物技术因特异性强、灵敏度高、简单快速等优势,在食品的农残检测中得到广泛应用和持续发展。分析了食品中农药残留及检测技术现状,综述了酶联免疫吸附测定法、荧光免疫法和生物条形码免疫法等分析技术,及电化学、光学、压电传感器等生物传感技术在食品农残检测中的应用进展,讨论了各种技术的优势和局限,以期为相关研究提供参考,从而进一步提高我国食品农残的检测效率,保障食品安全,促进我国食品行业的可持续发展。     

有机磷农药的微生物降解研究进展

微生物因种类和代谢多样性在有机磷农药降解中表现出独特的优势。对微生物降解有机磷农药的机制、微生物的获得、基因工程菌的构建及研究展望进行了综述。