HPLC Analysis of the Urinary Iodine Concentration in Pregnant Women

Iodine is an essential component for fetal neurodevelopment and maternal thyroid function. Urine iodine is the most widely used indicator of iodine status. In this study, a novel validated ion-pair HPLC–UV method was developed to measure iodine concentration in clinical samples. A sodium thiosulfate solution was added to the urine sample to convert the total free iodine to iodide. Chromatographic separation was achieved in a Pursuit XRs C8 column. The mobile phase consisted of acetonitrile and a water phase containing 18-crown-6-ether, octylamine and sodium dihydrogen phosphate. Validation parameters, such as accuracy, precision, limits of detection and quantification, linearity and stability, were determined. Urinary samples from pregnant women were used to complete the validation and confirm the method’s applicability. In the studied population of 93 pregnant women, the median UIC was lower in the group without iodine supplementation (117 µg/L, confidence interval (%CI): 95; 138) than in the supplement group (133 µg/L, %CI: 109; 157). In conclusion, the newly established ion-pair HPLC–UV method was adequately precise, accurate and fulfilled validation the criteria for analyzing compounds in biological fluids. The method is less complicated and expensive than other frequently used assays and permits the identification of the iodine-deficient subjects.     

孝感市1996年碘缺乏病防治监测结果分析

1996年9月采用PPS法在孝感市范围内对碘缺乏病(IDD)防治工作作了抽样监测。8～10岁儿童甲状腺肿大率(TGR)842%,其中查出Ⅱ°肿大3人,TGR≤5%的点占5333%;尿碘值<100μg/L占417%;M值为3855μg/L;居户盐碘2388×10-6±1216×10-6,<20×10-6的点占1667%,非碘盐占1167%。监测结果表明,本市8～10岁儿童TGR较1994年有下降;碘营养缺乏状况得到改善,碘代谢水平已达到IDD消除标准;碘盐的合格率仅7658%,离IDD消除标准还差近14个百分点。在本市IDD防治工作中实施的以供应加碘盐为主的综合防治措施是行之有效的,并取得了一定效果。揭示在今后的防治中,要进一步抓紧以供应加碘盐为主的综合防治措施。     

Studies on the Interaction of Poly(I:C) with Heterocyclic Compounds Containing Iodine

The iodine heterocvclic compound with trivalent-iodine as the cation has a specially remarkable antitumor activityii^[1]. Although 3, 6-bis (dimethylamino)-dibenzopyriodonium formate([I⁺]) inhibits DNA biosynthesis of cancer cells in vitro, the way of [I⁺] depressing DNA synthesis has not been studied. It is significant to investigate the mechanism of the interaction of [I⁺] with nucleic acids.     

混合表面活性剂在非极性溶剂中的聚集行为

表面活性剂在非极性溶剂中的聚集行为比在水溶液中复杂得多. 水溶液中表面活性剂有一明确的临界胶束浓度(CMC),而在非极性溶剂中至今对CM C概念仍有怀疑^[1], 但已有多种手段如染料增溶法、水增溶法、光散射法、荧光偏振、紫外和核磁共振谱等证实并测定了非极性溶剂中 CMC 的存在^[1～5]. 表面活性剂在非极性溶剂中以非离子化状态存在, 其缔合主要靠两亲分子之间的偶极-偶极以及离子对相互作用, 那么在一种表面活性剂溶液中加入另一种表面活性剂, 即表面活性剂的复配, 必然对其聚集行为产生重大影响, 但迄今为止, 尚未见关于混合表面活性剂在非极性溶剂中聚集行为的报道. 本文采用碘光谱法和水增溶法测定了阴离子表面活性剂AOT 和非离子表面活性剂 Brij30 混合后在正庚烷中形成反胶束的 CMC, 以期考察表面活性剂的复配对其聚集行为的影响。     

ICl3电离能的实验和理论研究

结合紫外光电子能谱实验和量子化学计算方法研究了三氯化碘的电离能．实验得到的ICl3的紫外光电子能谱是一氯化碘和氯气的混合能谱,这表明ICl3分解为ICl和Cl2．采用B3LYlP方法在6-311 G(df)基组水平上得到了ICl3分解的过渡态．计算表明ICl3分解吸收少量热量,反应的活化能为168．4kJ／mol．采用HF方法和外壳层格林函数方法(OVGF)预测了ICl3不同轨道的电离能,OVGF方法得到的ICl3第一垂直电离能为10．372eV．     

Visible absorption of iodine-doped polysilane with p-N,N-dialkylaminophenyl substituents

The doping effects on optical and electrical properties of polysilanes were investigated by in-situ measurement. When polysilanes bearing a p-N,N-dialkylaminophenyl substituent were doped with iodine vapor, drastic spectral changes were observed. The evolved visible absorption up to 700 nm was found to be strong and stable compared to that of iodine-doped polysilanes such as poly(methylphenylsilane). On the basis of the studies concerning iodine doping of the related p-N,N-dimethylaminophenyl-substituted silane and disilane, and also theoretical calculations, this new absorption can be best interpreted by the result of charge transfer consisting of the strong interaction between iodine and dialkylamino substituents in the polysilanes. © 1996 John Wiley & Sons, Inc.     

Cobaloximes as Environmentally Advantageous Alternatives to Organotin Hydrides in Iodine Atom Abstraction Routes to Benzyl Radicals

High yields of alkyl radicals derived from alkylcobaloximes have been achieved using tungsten light (or in some cases ultrasound) radiation in both organic and aqueous media. These improved yields are obtained when pyridine (the usual base ligand) is replaced by suitably bulky lone-pair donors or water. The alkyl radicals so generated take part in iodine abstraction reactions with benzyl iodide giving benzyl radicals which may be trapped in near-quantitative yield with 2,2,6,6-tetramethylpiperidinyloxy (TEMPO) or in good yield with lepidinium (4-methylquinolinium) trifluoroethanoate or lepidinium camphor-10-sulphonate. The usual drawbacks of cost and tedious work-up procedures associated with the more commonly used organotin hydride reagents are avoided.     

碘掺杂聚苯胺催化合成环己酮1,2-丙二醇缩酮

合成了聚苯胺-碘(PAn-I2)催化剂,并对其结构进行了表征。并通过环己酮与1,2-丙二醇合成环己酮1,2-丙二醇缩酮,探讨了PAn-I2对缩酮反应的催化活性。实验结果表明,PAn-I2是缩酮反应的良好催化剂,在环己酮100 mmol,n(环己酮)∶n(1,2-丙二醇)=1∶1.5,催化剂用量为反应物总质量的3%,环己烷12 mL,反应时间2 h的优化条件下,环己酮1,2-丙二醇缩酮的收率可达92.1%。     

Alkyliodines in High Oxidation State: Enhanced Synthetic Possibilities and Accelerated Catalyst Turn-Over

In contrast to aryliodine(III) compounds, which have matured into a particularly attractive class of oxidants in modern synthesis, the synthetic potential of related alkyliodine(III) derivatives has remained widely underestimated. This is surprising since several unique synthetic possibilities arise directly from the low stability of their central carbon–iodine bond. In this respect, these high-oxidation-state iodine compounds resemble environmentally benign variants of the prominent metal counterparts such as those derived from palladium, nickel and copper. This Concept article summarizes the general reactivity trends in alkyliodine(III) chemistry and discusses selected examples of their strategic use as highly reactive, transient species in organic synthesis and homogeneous catalysis.     

Iodine‐promoted Intermolecular Dehydrogenation Diamination: Synthesis of Unsymmetrical α,β‐Diamido Ketones

Iodine‐promoted direct diamination of α,β‐unsaturated ketone to form two C?N bonds has been developed starting from chalcone and secondary amine. This reaction was performed in THF at 50 °C in the presence of I₂ and K₂CO_3. The protocol is metal‐free, operationally simple and carried out under mild conditions, providing an effective new way for directing diamination reactions.