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作者合成了西佛碱水杨叉邻氧基苯酚和某些稀土元素固态配合物,这些配合物的组成分别为 RE.HL.L(RE=Ce Pr Nd)和 R_(B2)L_3,(RE=La Sm Eu Gd Lu),根据元素分析,电导、红外光谱、核磁、电子光谱和荧光光谱对配合物进行了表征。 相似文献
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The detection of circulating tumor DNA is a major challenge in liquid biopsies for cancer. Conventionally, quantitative polymerase chain reactions or next-generation sequencing are used to detect circulating tumor DNA; however, these techniques require significant expertise, and are expensive. Owing to the increasing demand for a simple diagnostic method and constant monitoring of cancer, a cost-effective detection technique that can be conducted by non-experts is required. The aim of this study was to detect the circulating tumor DNA containing the epidermal growth factor receptor (EGFR) exon 19 deletion, which frequently occurs in lung cancer. By applying walker DNA to a catalytic hairpin assembly and using the differential dispersibility of gold nanoparticles, we detected EGFR exon 19 deletion mutant #2 DNA associated with lung cancer. Our sensing platform exhibited a limit of detection of 38.5 aM and a selectivity of 0.1% for EGFR exon 19 wild-type DNA. Moreover, we tested and compared EGFR exon 19 deletion mutants #1 and #3 to evaluate the effect of base pair mismatches on the performance of the said technique. 相似文献
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紫外/可见分光光度法测定地呋麻滴鼻液中呋喃西林和盐酸麻黄碱的含量 总被引:1,自引:0,他引:1
目的建立地呋麻滴鼻液中呋喃西林和盐酸麻黄碱的含量测定方法,为制剂的质量控制提供有效分析方法。方法采用紫外-可见分光光度法测定地呋麻滴鼻液中呋喃西林和盐酸麻黄碱的含量。结果呋喃西林和盐酸麻黄碱在紫外-可见光区内有最大吸收,辅料等其他成分对两主药无干扰。本方法用于测定呋喃西林和盐酸麻黄碱的含量,回收率分别是99.5%、99.4%,RSD小于1.0%。结论方法专属性强,操作方便,结果准确,重现性好。 相似文献
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目的 比较金铁锁药材和植物细胞培养产生的植物愈伤组织、毛状根中总皂苷含量.方法 采用紫外可见分光光度法,以齐墩果酸为对照品,在波长535 nm处测定样品中的总皂苷含量.结果 齐墩果酸在0.008 112~0.048 672 mg/ml范围内呈现良好的线形关系,该法平均加样回收率为100.77%,RSD=2.44%(n= 9).测得金铁锁药材,金铁锁植物愈伤组织1,金铁锁植物愈伤组织2和金铁锁毛状根中总皂苷的含量分别为0.217%,0.388%,0.221%和0.857%.结论 金铁锁悬浮培养毛状根中总皂苷含量较高,应用价值较大. 相似文献
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地氯雷他定含量两种测定方法的比较 总被引:1,自引:0,他引:1
目的对地氯雷他定的含量测定两种方法进行比较。方法通过容量法(非水滴定法)及紫外分光光度法对地氯雷他定作含量方法比较。结果紫外分光光度法线性范围4.89~29.34 mg.L-1,r=0.999 99,精密度RSD为0.73%;非水滴定法精密度RSD为0.11%。结论容量法检测地氯雷他定含量操作简单,方法快速准确。 相似文献
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Monomers possessing hydrolytically-labile bonds to the bioactive agent β-naphthol (βN) were prepared for incorporation into hydrophilic copolymers. β-Naphthyl acrylate was synthesized by an esterification reaction of β-naphthol with acryloyl chloride. 5-Acrylamido(β-naphthyl)valerate, 2-acrylamido(β-naphthyl)isovalerate, 3-acrylamido-3-methyl(β-naphthyl)butanoate, and 6-acrylamido(β-naphthyl)caproate were synthesized by esterification of βN with 5-acrylamidovaleric acid, 2-acrylamidovaleric acid, 3-acrylamido-3-methylbutanoic acid, and 6-acrylamidocaproic acid, respectively, utilizing 1,3-dicyclohexylcarbodiimide as a coupling agent and 4-dimethylaminopyridine as a catalyst. The βN monomers were free radically polymerized with acrylic acid, utilizing AIBN as initiator in benzene at 70°C to obtain polymer-bound allelopathic βN. Copolymer composition was determined by 1H-NMR, 13C-NMR, FTIR, and UV-vis. spectroscopy. The copolymerization reactivity ratios were calculated from 1H-NMR data using Fineman-Ross, Kelen-Tudos (K-T), and nonlinear least-squares methods. Copolymer microstructural predictions were determined from calculated K-T reactivity ratios. The resulting water soluble copolymers prepared in this work are potentially useful as plant growth regulators through the hydrolytic release of β-naphthol. These model structures have been utilized for the determination of structure/controlled release relationships reported in an accompanying publication. 相似文献