共查询到17条相似文献,搜索用时 203 毫秒
1.
(阳离子表面活性剂-I3)n缔合微粒体系的光谱特性及分析应用 总被引:3,自引:0,他引:3
在0.01 mol/L HCl介质中,I-3在350 nm处有一吸收峰;当十六烷基三甲基溴化铵(CTMAB)与I-3共存时体系呈红紫色,在550 nm处产生一新的吸收峰.CTMAB浓度CCTMAB在0.0~7.0×10-5 mol/L范围内符合比耳定律,回归方程为A550 nm =0.989×104 CCTMAB+0.0138,相关系数R为0.999 5,摩尔吸光系数ε为1.06×104 L/(mol·cm),据此建立了一种测定阳离子表面活性剂含量的分光光度新方法,并用于合成样品和新洁尔净样品中阳离子表面活性剂测定.共振散射光谱研究表明,CTMAB+与I-3可通过静电引力作用形成疏水性的CTMA-I3缔合物分子,并进一步聚集形成稳定的 (CTMA-I3)n缔合微粒.由于该缔合微粒在580 nm处产生共振散射效应,故体系呈红紫色. 相似文献
2.
在稀HCl介质中,I-3在340 nm处有一吸收峰;当小檗碱(BB)与I-3共存时体系呈橙黄色,在580 nm处产生一共振散射峰.以试剂作参比,该缔合微粒体系在530 nm产生一吸收峰,BB浓度在0~7.0×10-5mol/L范围内与A530 nm呈线性,据此建立了一种测定小檗碱含量的分光光度新方法,并用于针剂样品中小檗碱测定,结果满意.同步散射光谱研究表明,BB+与I-3可通过静电引力作用形成疏水性的(I3-BB)缔合物分子,并进一步聚集形成稳定的(I3-BB)n缔合纳米微粒.由于该缔合纳米微粒在580 nm处产生共振散射效应,故体系呈橙黄色. 相似文献
3.
(PtI6-2RDG)n缔合纳米微粒体系的共振散射、荧光猝灭和减色效应研究 总被引:5,自引:3,他引:5
在0.02mol/L HCl介质中,罗丹明6G(RDG)分别在530nm和550nm处有一个吸收峰和荧光峰,PtI6^2-与RDG^ 主要通过静电引力形成疏水性的PtI6-2RDG缔合物分子。PtI6-2RDG分子间存在较强的分子和和疏水作用力而生成(PtI6-2RDG)n缔合纳米微粒,其粒径为40nm,在400nm、470nm和590nm产生3个共振散射,其中400nm和590nm处的2个峰为其特征共振散射峰,550nm荧光峰和530nm吸收峰的降低是由于纳米微粒形成后,只有裹露在(PtI6-2RDG)n纳米微粒界面的RDG荧光分子才能吸收激发光子跃迁到激发态,进而返回基态产生荧光,而体体相的RDG荧光分子无法与激发光作用产生荧光,即与激发光作用的RDG分子数大为降低。当该纳米微粒体系加入乙醇后,由于乙醇致使(PtI6-2RDG)n纳米微粒分解为PtI6-2RDG分子,体系的红紫色和共振散射峰消失,吸收峰和荧光峰恢复,研究结果表明,红紫色(PtI6-2RDG)n纳米微粒的形成是其共振散射增强、荧光猝灭、减色效应和产生特征共振散射峰的根本原因。 相似文献
4.
氯金酸-罗丹明S缔合纳米微粒体系的共振散射增强与荧光猝灭研究 总被引:8,自引:0,他引:8
在0.2mol/L HCl介质中,罗丹明S(RDS)分别在520nm和550nm处有一个吸收峰和荧光峰。当有Au(Ⅲ)存在时,Au(Ⅲ)与Cl^-形成AuCl4^-,AuCl^-与RDS^ 借助于静电引力形成疏水性的AuCl4-RDS缔合物分子。AuCl4-RDS分子间存在较强的分子间作用力和疏水作用力而生成(AuCl4-RDS)。缔合纳米微粒,粒径为45nm。在360nm产生瑞利散射峰,在600nm产生共振散射峰。由于纳米微粒形成后,只有裹露在(AuCl4-RDS)n纳米微粒界面的RDS荧光分子才能吸收激发光子跃迁到激发态,进而返回基态产生荧光。而体相的RDS荧光分子无法与激发光作用产生荧光,即受激RDS分子数大为降低,故550nm荧光峰和520nm吸收峰的降低。当缔合纳米微粒体系加入乙醇后,体系的红紫色和共振散射峰消失,吸收峰和荧光峰恢复,由于乙醇致使(AuCl4-RDS)。纳米微粒分解为AuCl4-RDS分子。结果表明:红紫色(AuCl4-RDS)n纳米粒子的形成是其共振散射增强、荧光猝灭和产生共振散射峰的根本原因。 相似文献
5.
在稀HCl介质中,I-3在340 nm处有一吸收峰;当小檗碱(BB)与I-3共存时体系呈橙黄色,在580 nm处产生一共振散射峰.以试剂作参比,该缔合微粒体系在530 nm产生一吸收峰,BB浓度在0~7.0×10-5mol/L范围内与A530 nm呈线性,据此建立了一种测定小檗碱含量的分光光度新方法,并用于针剂样品中小檗碱测定,结果满意.同步散射光谱研究表明,BB+与I-3可通过静电引力作用形成疏水性的(I3-BB)缔合物分子,并进一步聚集形成稳定的(I3-BB)n缔合纳米微粒.由于该缔合纳米微粒在580 nm处产生共振散射效应,故体系呈橙黄色. 相似文献
6.
Pt(IV)与I-形成[PtI6]2-,[PtI6]2-和盐酸西替利嗪(CTRZ)通过静电引力作用形成疏水性的(PtI6—CTRZ)缔合物分子.由于(PtI6-CTRZ)缔合物分子间存在较强的分子间作用力和疏水作用力而生成紫红色(CTRZ—PtI6)n缔合微粒,在310、400、610nm处产生3个共振散射峰;在350~740nm波长范围的吸光度值均增大.在选定条件下,CTRZ浓度在0~10μg/mL范围内与A580nm成正比,摩尔吸光系数ε580nm为1.30×104L/(mol·cm).实验结果表明,(CTRZ—PtI6)n缔合微粒的形成是导致同步散射信号增强的根本原因,而纳米纳米微粒的颜色是共振散射所致. 相似文献
7.
在稀HCl介质中,I_3~-在340 nm处有一吸收峰;当小檗碱(BB)与I_3~-共存时体系呈橙黄色,在580 nm处产生一共振散射峰。以试剂作参比,该缔舍微粒体系在530 nm产生一吸收峰,BB浓度在0~7.0×10~(-5)mol/L范围内与A_(530nm)呈线性,据此建立了一种测定小檗碱含量的分光光度新方法,并用于针剂样品中小檗碱测定,结果满意。同步散射光谱研究表明,BB~+与I_3~-可通过静电引力作用形成疏水性的(I_3-BB)缔合物分子,并进一步聚集形成稳定的(I_3-BB)_n缔合纳米微粒。由于该缔合纳米微粒在580 nm处产生共振散射效应,故体系呈橙黄色。 相似文献
8.
盐酸小檗碱-十二烷基苯磺酸钠缔合微粒体系的共振散射光谱研究及其分析应用 总被引:3,自引:0,他引:3
在pH 4 .80NaAc HAc缓冲介质中 ,盐酸小檗碱 (BH)与十二烷基苯磺酸钠 (DBS)由于静电引力和疏水作用力形成缔合微粒 ,在 4 70nm处有一共振散射峰。随着DBS浓度增大 ,该峰急剧增强 ,即存在缔合微粒的散射光增强效应 ;345nm处的吸光度减弱 ,即存在缔合微粒的减色效应。研究了共振散射光谱测定BH的影响因素 ,提出了测定 (0 .35~ 4 .4 )× 10 -5mol/L盐酸小檗碱的共振散射光谱新方法 ,用于复方黄连素片剂和针剂样品的测定 ,结果满意 相似文献
9.
在HCl-NaOAc酸性缓冲介质中,曙红Y(EY)与盐酸吡格列酮(PGH)反应形成1∶1的离子缔合物,不仅引起曙红Y的荧光猝灭(FLU),更能导致共振散射(RRS)的显著增强。荧光猝灭的激发和发射波长分别为λex=524nm和λem=544nm;最大共振散射波长为308nm,并在540nm处产生一共振峰。方法的线性范围分别为9.04×10-7~2.05×10-5mol/L(FLU)和1.6×10-7~5.1×10-6mol/L(RRS),检出限分别为1.88×10-7mol/L(FLU)和4.82×10-8mol/L(RRS)。研究了荧光和共振散射的光谱特征、适宜的反应条件及影响因素,据此建立了灵敏、简便、快速测定抗糖尿病药物盐酸吡格列酮的新方法。 相似文献
10.
IO3--I--亚甲基蓝-阿拉伯胶-聚乙烯醇体系分光光度法测定微量碘 总被引:3,自引:0,他引:3
在pH 3.8苯二甲酸氢钾-盐酸介质中,有阿拉伯胶和聚乙烯醇存在下,IO-3氧化I-生成I-3,I-3再与亚甲基蓝形成离子缔合物,缔合物的最大吸收波长为525 nm,表观摩尔吸光系数ε525=1.32×105 L/(mol·cm),IO-3浓度在0~30 μg/25 mL范围内服从比尔定律. 方法用于碘盐和生物样品中碘的测定,结果满意. 相似文献
11.
Under the conditions of 0.04 mol L−1 HCl-8.0 × 10−4 mol L−1 KI, there is a fluorescence peak at 540 nm and a synchronous fluorescence peak at 540 nm for rhodamine 6G (RhG). When there is IO3−, it reacts with exceed I− to form I3−. And I3− and RhG combine into ion association particles. The particles exhibit three resonance scattering peaks at 320, 400 and 595 nm. And there is fluorescence quenching at 540 nm. Iodine concentration is proportional to the intensity of the resonance scattering intensity at 400 nm in the range of 1.0-20 × 10−7 mol L−1. And a new resonance scattering spectral (RSS) method has been described for the determination of IO3− in salt samples. The spectral results have been verified that the formation of (RhG-I3)n association particles and solid-liquid interfaces are the main factor that cause the fluorescence quenching and resonance scattering effects. 相似文献
12.
Based on resonance scattering (RS) effect of rhodamine dye association particles, a new resonance scattering method for the determination of hydroxyl free radical from Fenton reaction was developed. In HCl-NaAc buffer solution, the OH of Fenton reaction oxidized the excess I− to I3−. The I3− combined, respectively, with rhodamine B (RhB), butyl rhodamine B (b-RhB), rhodamine 6G (RhG) and rhodamine S (RhS) to form association particles that exhibit stronger resonance scattering effect at 420 nm and 610 nm. However, the RS peak at about 610 nm was interfered with its synchronous fluorescence peak at 580 nm for RhB, 580 nm for b-RhB, 560 nm for RhG and 560 nm for RhS, respectively. The concentration of H2O2 in the range of 0.648-21.6 μmol/L, 0.423-13.0 μmol/L, 0.216-13.0 μmol/L and 0.092-13.0 μmol/L was linear to its resonance scattering intensity at 420 nm. Its detection limit was 0.15 μmol/L, 0.10 μmol/L, 0.092 μmol/L and 0.044 μmol/L, H2O2, respectively. This RhS RS method was applied to selection of the antioxidant, with satisfactory results. 相似文献
13.
In Na2HPO4-citric acid buffer solution, Cl2 can oxidize I− to form I2 and then it reacts with excess I− to form I3−. The I3− combines respectively with rhodamine dyes, including rhodamine B (RhB), butyl rhodamine B (b-RhB), rhodamine 6G (RhG) and rhodamine S (RhS), to form association particles which give stronger resonance scattering (RS) effect at 400 nm. The RS intensity of the RhB, b-RhB, RhG and RhS systems is proportional to chlorine concentrations in the range of 0.008-1.74, 0.019-1.33, 0.021-2.11 and 0.019-2.04 μg/mL Cl2, respectively. The detection limits of the systems were 0.0020, 0.0048, 0.0063 and 0.0017 μg/mL, respectively. In them, the RhB system has good stability and high sensitivity, and has been applied to the analysis of chlorine in drinking water, with satisfactory results which is in agreement with that of the methyl orange (MO) spectrophotometry. 相似文献
14.
A procedure is developed for the selective photometric determination of selenium(IV) in bottled drinking water by the oxidation of Methylene Blue in 1 M HCl to colorless decomposition products and of selenium(VI) by its interaction with the specified reagent at pH 5–6 with the formation of a colored ion pair. The limits of detection are 1 and 0.8 µg/L, respectively. At the concentration of selenium(IV) 2 µg/L, the admissible weight ratios are: SeO42-, Br3- (1: 20); Br– (1: 60); I–, IO3- and IO4- (1: 100). At equal concentration of selenium(VI), the following species: SeO42-(1: 20); Br3-, Br–, I–, IO3-, and IO4- (1: 100) do not interfere with the determination. Other anions and cations present in highly mineralized waters do not interfere with the determination. The relative error of determination is 8–10% in the concentration range 2–10 µg/L of selenium(IV) and selenium(VI) and does not exceed 5% in their concentration range of 10–100 µg/L. 相似文献
15.
CdTe nanocrystals (CdTe NCs) were achieved by reaction of CdCl2 with KHTe solution and were capped with sodium mercaptoacetate. The product was detected by transmission electron microscopy
(TEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive spectroscopy (EDS), fluorescence spectra,
ultraviolet-visible spectra and X-ray diffraction (XRD). The CdTe NCs are of cubic structure and the average size is about
5 nm. The fluorescence quantum yield of CdTe NCs aqueous solution increased from 37% to 97% after 20 d under room light. The
maximum λ
em of fluorescence changed from 543 nm to 510 nm and the blue shift was 33 nm. CdTe NCs aqueous solution can be steady for at
least 10 months at 4 in° a refrigerator. The resonance Rayleigh scattering (RRS) of CdTe NCs in the aqueous solution was investigated.
The maximum scattering peak was located at about 554 nm. The interactions of CdTe NCs with amikacin sulfate (AS) and micronomicin
sulfate (MS) were investigated respectively. The effects of AS and MS on fluorescence and RRS of CdTe NCs were analyzed. It
was found that AS and MS quenched the photoluminescence of CdTe NCs and enhanced RRS of CdTe NCs. Under optimum conditions,
there are linear relationships between quenching intensity (F
0-F), intensity of RRS (I-I
0) and concentration of AS and MS. The detection limits (3б) of AS and MS are respectively 3.4 ng·mL−1 and 2.6 ng·mL−1 by the fluorescence quenching method, and 15.2 ng·mL−1 and 14.0 ng·mL−1 by the RRS method. The methods have high sensitivity, thus CdTe NCs may be used as fluorescence probes and RRS probes for
the detection of aminoglycoside antibiotics.
Supported by the National Natural Science Foundation of China (Grant No. 20475045) 相似文献
16.
17.
用鲱鱼精DNA (hsDNA)修饰10 nm的纳米金制备了Hg2+的hsDNA修饰纳米金共振散射光谱探针(AuhsDNA). 在pH 7.0 Tris-HCl缓冲溶液中及0.017 mol/L NaCl存在下, Hg2+与AuhsDNA形成稳定的Hg2+-DNA结合物, 引起AuhsDNA中的纳米金析出并聚集形成纳米金簇. 该溶液用150 nm滤膜过滤后, 滤液中过量的AuhsDNA可催化Fehling试剂-葡萄糖反应生成氧化亚铜微粒, 该微粒在580 nm处有一个较强的共振散射峰. 随着汞离子浓度增大, 形成的纳米金簇越多, 滤液中AuhsDNA越少, 生成的氧化亚铜微粒减少, 580 nm处氧化亚铜微粒的共振散射光强度线性降低, 其共振散射光强度降低值?I580 nm与汞离子浓度在1~833 nmol/L范围内成线性, 回归方程、相关系数、检出限分别为
?I580 nm+0.9, 0.9990, 0.3 nmol/L Hg2+. 该法用于废水中Hg2+的检测. 相似文献