Resonance Rayleigh scattering, frequency doubling scattering and second-order scattering spectra of the heparin-crystal violet system and their analytical application

In pH 6.0-11.2 Britton-Robinson buffer solution, binding of heparin with crystal violet (CV) can result in a significant enhancement of resonance Rayleigh scattering (RRS) and resonance non-linear scattering, such as frequency doubling scattering (FDS) and second-order scattering (SOS). Their maximum scattering wavelengths, λ_ex/λ_em, appear at 492 nm/492 nm for RRS, 984 nm/492 nm for FDS and 492 nm/984 nm for SOS, respectively. The optimum conditions of the reaction, the influencing factors and the relationship between the three scattering intensities and the concentration of heparin have been investigated. New methods for the determination of trace amounts of heparin based on the RRS, FDS and SOS methods have been developed. The methods exhibit high sensitivities, the detection limit for heparin is 2.9 ng ml⁻¹ for the RRS method, 3.5 ng ml⁻¹ for the FDS method and 3.3 ng ml⁻¹ for the SOS method. The methods have good selectivity and were applied to the determination of heparin in heparin sodium injection samples with satisfactory results.     

Study on the resonance Rayleigh scattering spectra and resonance non-linear spectra of congo red-amikacin system and its analytical application

The interaction between congo red (CR) and amikacin (AMK) was studied by resonance Rayleigh scattering (RRS), frequency doubling scattering (FDS) and second-order scattering (SOS) combining with absorption spectrum. In a weak acidic medium, CR combined with AMK to form an ion association complex with the composition ratio of 1∶1 by electrostatic interaction, hydrophobicity and charge transferring effect. As a result, the new spectra of RRS, FDS, and SOS appeared and their intensities were enhanced greatly. The maximum wavelengths of RRS, FDS and SOS were located at 563 nm, 475 nm and 940 nm, and the scattering intensities were proportional to the concentration of AMK. These three methods have very high sensitivities, and the detection limits were 4.0 ng·mL?1 for RRS, 3.6 ng·mL?1 for FDS and 1.9 ng·mL?1 for SOS, respectively. At the same time, the methods have better selectivity. A new method for the determination of trace amounts of AMK with congo red by resonance scattering technique has been developed. The recovery for the determination of AMK in blood serum and urine sample was between 95.5% and 105.5%. In this study, the properties, such as enthalpy of formation, charge distribution and mean polarizability, were calculated by AM1 quantum chemistry method. In addition, the reaction mechanism and the reasons for the enhancement of scattering spectra were discussed.     

Resonance Rayleigh scattering spectral method for the determination of raloxifene using gold nanoparticle as a probe

When gold nanoparticles were being prepared by sodium citrate reduction method, citrate anions self-assembled on the surface of gold nanoparticles to form supermolecular complex anions with negative charges, and protonated raloxifene (Ralo) was positively charged and could bind with the complex anions to form larger aggregates through electrostatic force and hydrophobic effects, which could result in the remarkable enhancement of the resonance Rayleigh scattering intensity (RRS), and the appearance of new RRS spectra. At the same time, the second-order scattering (SOS) and frequency-doubling scattering (FDS) intensities were also enhanced. The maximum wavelengths were located near 370 nm for RRS, 520 nm for SOS, and 350 nm for FDS, respectively. Among them, the RRS method had the highest sensitivity and the detection limit was 5.60 ng mL⁻¹ for Ralo, and its linear range was 0.05-2.37 μg mL⁻¹. A new RRS method for the determination of trace Ralo using gold nanoparticles probe was developed. The optimum conditions of the reaction and influencing factors were investigated. In addition, the reaction mechanism and the reasons for the enhancement of RRS were discussed.     

Analytical Application of Resonance Rayleigh Scattering,Frequency Doubling Scattering,and Second-Order Scattering Spectra for the Sodium Alginate-CTAB System

Three new methods for the determination of trace amounts of sodium alginate (SA) based on the reaction of SA with cetyltrimethylammonium bromide (CTAB) by resonance Rayleigh scattering (RRS), frequency doubling scattering (FDS), and second-order scattering (SOS) have been investigated. The SA can react with CTAB in a pH 10.0 Britton–Robinson buffer to form a new product, which can lead to a significant enhancement of RRS, FDS, and SOS intensities and appearance of new spectra. The maximum scattering wavelengths, λex/λem, appear at 351 nm/351 nm for RRS, 240 nm/480 nm for SOS, and 870 nm/435 nm for FDS, respectively. The increments of the scattering intensities (ΔI) are proportional to the concentration of SA in a certain range. The detection limits (3σ) for SA are 3.69 ng mL^?1 for the RRS method, 6.91 ng mL^?1 for the FDS method, and 7.45 ng mL^?1 for the SOS method under optimum conditions. The proposed methods were applied to the determination of SA in real samples with satisfactory results.     

The interaction between furosemide-palladium (II) chelate and basic triphenylmethane dyes by resonance Rayleigh scattering spectra and resonance non-linear scattering spectra and their analytical applications

In pH 4.5–7.0 Britton-Robinson buffer solution, furosemide (FUR) reacted with Pd (II) to form a 1:1 anionic chelate. This chelate could further react with such basic triphenylmethane dyes (BTPMD) as ethyl violet (EV), crystal violet (CV), methyl violet (MV), methyl green (MeG) and brilliant green (BG) to form 1:1 ion-association complexes. This not only resulted in the change of absorption spectra, but also led to the significant enhancement of resonance Rayleigh scattering (RRS), second-order scattering (SOS) and frequency doubling scattering (FDS). The maximum RRS wavelengths were located at 324 nm for the EV, CV and MV system, and 340 nm for the BG and MeG system. The maximum SOS wavelengths were located at 550 nm for the EV, CV, BG and MeG system, and 530 nm for the MV system. The maximum scattering peaks of all the systems were at 392 nm for FDS. The enhanced RRS, SOS and FDS intensities were directly proportional to the concentration of FUR. The detection limits for the different dye systems were 0.3–4.9 ng mL^?1 for the RRS method, 3.2–33.1 ng mL^?1 for the SOS method and 9.0–85.7 ng mL^?1 for the FDS method. These methods could be used for the determination of trace amounts of FUR. The effects of the formation of ternary ion-association complexes on the spectral characteristics and intensities of absorption, RRS, SOS and FDS have been investigated. The optimum conditions of these reactions, the influencing factors and the analytical properties have been tested. The influences of coexisting substances were tested by RRS method and the results showed that this method exhibited a high sensitivity. Based on the aforementioned research, the highly sensitive, simple and rapid methods for the determination of trace amounts of FUR by resonance light scattering technique have been established, which could be applied to the determination of FUR in tablet, injection, human serum and urine samples. The composition and structure of the ternary ion-association complex and the reaction mechanism were discussed.     

金纳米微粒作探针共振瑞利散射光谱法测定卡那霉素

在一种含柠檬酸盐的溶液中, 柠檬酸根阴离子自组装于带正电荷的金纳米微粒表面, 使金纳米微粒成为一种被柠檬酸根包裹的带负电荷的超分子化合物. 在pH 4.4～6.8的弱酸性介质中, 它可与质子化的卡那霉素(KANA)阳离子借静电引力、疏水作用力结合, 形成粒径更大的聚集体(平均粒径从12增至20 nm), 这种聚集体的形成在引起金纳米的等离子体吸收带明显红移(Δλ＝102 nm)的同时, 共振瑞利散射(RRS)显著增强并且倍频散射(FDS)和二级散射(SOS)等共振非线性散射也有较大的增强, 最大散射峰分别位于280 nm (RRS), 310 nm (FDS)和480 nm (SOS)处. 在适当条件下, 散射强度(ΔI)与卡那霉素的浓度成正比, 其中RRS法灵敏度最高, 因此金纳米微粒可作为测定卡那霉素的高灵敏RRS探针, 它对卡那霉素的检出限为10.52 ng•mL^－1, 方法有较好的选择性, 可用于血液中卡那霉素的测定, 文中还讨论了有关反应机理和RRS增强的原因.     

Study on the interaction among molecules and the determination of DNA by light scattering with a new type rhodanine derivative

In this paper the resonance Rayleigh scattering (RRS) and second-order scattering (SOS) spectrums of interaction between deoxyribonucleic acid (DNA) and 3-(4′-methylphenyl)-5-(2′-sulfophenylazo) rhodanine (4MRASP) in the environment of surface active substance sodium dodecyl sulfate (SDS) were reported. The light scattering intensity of 4MRASP was enhanced obviously and directly proportional to the concentrations of DNA when DNA was present. Based on this, two new determination methods of DNA were established with high sensitivity and selectivity, and the limits of detection were 8.00 and 1.07 ng mL⁻¹. They were applied to the determination of trace amounts of nucleic acid in synthetic and practical samples with satisfactory results. At last, the active mechanism among molecules was studied by ultraviolet spectrum, scattering spectrum and thermodynamics, which showed that the active force was changed from hydrophobic force to electrostatic force before and after SDS was added, and the mechanism of sensitization effect of SDS was proposed.     

Study on the interaction between CdSe quantum dots and chitosan by scattering spectra

Two different stabilizing agents thioglycolic acid (TGA) and l-cysteine (l-Cys) capped CdSe QDs with the diameter of 2 nm were synthesized, large amounts of stabilizing agents connected to CdSe QDs surface through Cd–S bond. The interaction between chitosan and QDs had been investigated, respectively. The interaction lead to the remarkable enhancement of RRS, RNLS and the enchantments were in proportional to the concentration of chitosan in a certain range. Under the optimal conditions, compared with TGA–CdSe QDs, the interaction between l-Cys–CdSe QDs with chitosan owned more broad linear range 0.042–3.0 μg mL⁻¹ and lower detect limits 1.2 ng mL⁻¹. The influences of factors on the interaction between chitosan with QDs and some foreign substances were all examined, which showed that the methods had a good sensitivity and selectivity. Based on this, it is hoped to build a method for the determination of chitosan using CdSe QDs as probes. Through Fourier transform infrared spectroscopy (FTIR) transmission electron microscopy (TEM), it was speculated that CdSe QDs interacted with chitosan to form a network structure aggregates through electrostatic attraction and hydrophobic forces. The reasons for the enhancement of RRS intensity were assumed as follows: resonance enhanced Rayleigh scattering effect, increase of the molecular volume, and hydrophobic effect.     

A study on the sizes and concentrations of gold nanoparticles by spectra of absorption, resonance Rayleigh scattering and resonance non-linear scattering

Liquid phase gold nanoparticles with different diameters and colors can be prepared using sodium citrate reduction method by controlling the amounts of sodium citrate. The mean diameters of gold nanoparticles are measured by transmission electron microscope (TEM). Gold nanoparticles with different sizes have specific absorption spectra. When the diameters of nanoparticles is between 12 and 41 nm, the maximum absorption peaks locate at 520-530 nm and there are red shifts gradually with the increase of diameters of gold nanoparticles. And when the size of gold nanoparticle is constant, the absorbance is proportional to the concentration of gold. Obvious resonance Rayleigh scattering (RRS) and the resonance non-linear scattering such as second-order scattering (SOS) and frequency-doubling scattering (FDS) appear at the same time as well, and the maximum scattering peaks are located at 286 nm (RRS), 480 nm (SOS) and 310 nm (FDS), respectively. When the concentration of gold is constant, absorbance and the intensities of RRS, SOS and FDS (I(RRS), I(SOS) and I(FDS)) have linear relationships with the diameters of gold nanoparticles. When the diameter of gold nanoparticle is constant, the absorbance and I(RRS), I(SOS), I(FDS) are directly proportional to the concentrations of gold nanoparticles. Therefore, it is very useful for studying the liquid phase gold nanoparticles by investigating the absorption, RRS, SOS and FDS spectra.     

Second‐order Scattering and Frequency Doubling Scattering Spectra of Thallium(III)‐Methotrexate System and Its Analytical Application

In pH 4.9 Britton-Robinson buffer solution, methotrexate (MTX) reacted with thallium(III) to form a 3∶1 chelate. This resulted in great enhancement of second-order scattering (SOS) spectra and frequency doubling scattering (FDS) spectra and appearance of new SOS and FDS spectra. Their maximum wavelengths were located at 520 and 390 nm, respectively. The increments of scattering intensities (ΔI) were directly proportional to the concentrations of MTX in the ranges of 0.022—2.0 μg•mL－1 (SOS method) and 0.008—2.5 μg•mL－1 (FDS method). The methods exhibited high sensitivities. The detection limits for MTX were 7.4 ng•mL－1 (SOS method) and 2.3 ng•mL－1 (FDS method), respectively. The optimum conditions of the reaction, the influencing factors and the effects of coexisting substances were investigated. A highly sensitive, simple and fast method for the determination of MTX has been developed. The method can be applied satisfactorily to the determination of MTX in human serum samples. In this work, the charge distribution of MTX was calculated by a CNDO quantum chemistry method. In addition, the reaction mechanism was discussed.     

Resonance Rayleigh scattering, second-order scattering and frequency doubling scattering methods for the indirect determination of penicillin antibiotics based on the formation of Fe3[Fe(CN)6]2 nanoparticles

Under the HCl solution and heating condition, penicillin antibiotics such as amoxicillin (AMO), ampicillin (AMP), sodium cloxacillin (CLO), sodium carbenicillin (CAR) and sodium benzylpenicillin (BEN) could react with Fe(III) to produce Fe(II) which further reacted with Fe(CN)₆³⁻ to form a Fe₃[Fe(CN)₆]₂ complex. By virtue of hydrophobic force and Van der Waals force, the complex aggregated to form Fe₃[Fe(CN)₆]₂ nanoparticles with an average diameter of 45 nm. This resulted in a significant enhancement of resonance Rayleigh scattering (RRS) and non-linear scattering such as second-order scattering (SOS) and frequency doubling scattering (FDS). The increments of scattering intensity (ΔI) were directly proportional to the concentrations of the antibiotics in a certain range. The detection limits for the five penicillin antibiotics were 2.9–6.1 ng ml⁻¹ for RRS method, 4.0–6.8 ng ml⁻¹ for SOS method and 7.4–16.2 ng ml⁻¹ for FDS method, respectively. Among them, the RRS method exhibited the highest sensitivity and the AMO system was more sensitive than other antibiotics systems. Based on the above researches, a new highly sensitive and simple method for the indirect determination of penicillin antibiotics has been developed. It can be applied to the determination of penicillin antibiotics in capsule, tablet, human serum and urine samples. In this work, the spectral characteristics of absorption, RRS, SOS and FDS spectra, the optimum conditions of the reaction and the influencing factors were investigated. In addition, the reaction mechanism was discussed.     

Effects of interaction of folic acid with uranium (VI) and basic triphenylmethane dyes on resonance Rayleigh scattering spectra and their analytical applications

In pH 4.2-4.8 HAc-NaAc buffer solution, folic acid (FA) could react with uranium (VI) to form a 2:1 anionic chelate which further reacted with some basic triphenylmethane dyes (BTPMD) such as Ethyl Violet (EV), Methyl Violet (MV) and Crystal Violet (CV) to form 1:2 ion-association complexes. As a result, not only the absorption spectra were changed, but also the intensities of resonance Rayleigh scattering (RRS) were enhanced greatly and the new RRS spectra were observed. The maximum RRS wavelengths were located at 328 nm for EV system, 325 nm for MV system and 328 nm for CV system. The fading degree (ΔA) and RRS intensities (ΔI) of three systems were different. Under given conditions, the ΔA and ΔI were all directly proportional to the concentration of FA. The linear ranges and the detection limits of RRS methods were 0.0039-5.0 μg mL⁻¹ and 1.2 ng mL⁻¹ for EV system, 0.0073-4.0 μg mL⁻¹ and 2.2 ng mL⁻¹ for MV system, 0.014-3.5 μg mL⁻¹ and 4.7 ng mL⁻¹ for CV system. The RRS methods exhibited higher sensitivity, so they are more suitable for the determination of trace FA. The optimum conditions, the influencing factors and the effects of coexisting substances on the reaction were investigated. The method can be applied to the determination of FA in serum and urine samples with satisfactory results. The structure of the ternary ion-association complex and the reaction mechanism were discussed in this work.     

Study on the resonance Rayleigh scattering spectra of the interactions of palladium (II)-cephalosporins chelates with 4,5-dibromofluorescein and their analytical applications

In pH 2.8-3.8 BR buffer medium, the third generation cephalosporin antibiotics (TGCs) such as ceftazidime (CZD), ceftriaxone (CTRX), cefoperazone (CPZ), and cefotaxime (CFTM) react with palladium(II) (Pd(II)) to form 1:2 yellowish-brown cationic chelates, which further react with 4, 5-dibromofluorescein (DBF) to form 1:3 brown ion-association complexes. As a result, not only the spectra of absorption and fluorescence are changed, but also the resonance Rayleigh scattering (RRS) is enhanced greatly and the new RRS spectra are observed. The four TGCs products have similar spectral characteristics and their maximum RRS wavelengths are all located at 291 nm. The quantitative determination ranges and the detection limits of the four TGCs are 0.0065-1.0 μg mL⁻¹ and 2.0 ng mL⁻¹ for CZD, 0.0070-1.1 μg mL⁻¹ and 2.2 ng mL⁻¹ for CTRX, 0.0090-1.6 μg mL⁻¹ and 2.7 ng mL⁻¹ for CPZ, and 0.014-2.2 μg mL⁻¹ and 4.2 ng mL⁻¹ for CFTM, respectively. The optimum conditions of the reactions and the effects of foreign substances are investigated, and the composition of ion-association complexes is discussed also. Based on the ion-association reaction, a highly sensitive, simple and rapid method has been proposed to the determination of TGCs.     

Rapid and sensitive spectrofluorimetric determination of enrofloxacin, levofloxacin and ofloxacin with 2,3,5,6-tetrachloro-p-benzoquinone

A highly sensitive spectrofluorimetric method was developed for the first time, for the analysis of three fluoroquinolones (FQ) antibacterials, namely enrofloxacin (ENR), levofloxacin (LEV) and ofloxacin (OFL) in pharmaceutical preparations through charge transfer (CT) complex formation with 2,3,5,6-tetrachloro-p-benzoquinone (chloranil,CLA). At the optimum reaction conditions, the FQ–CLA complexes showed excitation maxima ranging from 359 to 363 nm and emission maxima ranging from 442 to 488 nm.Rectilinear calibration graphs were obtained in the concentration range of 50–1000, 50–1000 and 25–500 ng mL⁻¹ for ENR, LEV and OFL, respectively.The detection limit was found to be 17 ng mL⁻¹ for ENR, 17 ng mL⁻¹ for LEV, 8 ng mL⁻¹ for OFL, respectively. Excipients used as additive in commercial formulations did not interfere in the analysis. The method was validated according to the ICH guidelines with respect to specificity, linearity, accuracy, precision and robustness. The proposed method was successfully applied to the analysis of pharmaceutical preparations. The results obtained were in good agreement with those obtained using the official method; no significant difference in the accuracy and precision as revealed by the accepted values of t- and F-tests, respectively.     

Resonance Rayleigh scattering, second-order scattering and frequency doubling scattering spectra for studying the interaction of erythrosine with Fe(phen)3(2+) and its analytical application

In a weak alkaline Britton-Robinson buffer medium, erythrosine (Ery) can react with Fe(phen)(3)(2+) to form 1:1 ion-association complex, which will cause not only the changes of the absorption spectra, but also the remarkable enhancement of resonance Rayleigh scattering (RRS), second-order scattering (SOS) and frequency doubling scattering (FDS) spectra, and the appearance of new spectra of RRS, SOS and FDS. The maximum RRS, SOS and FDS wavelengths (λ(ex)/λ(em)) of the ion-association complex are located at 358/358 nm, 290/580 nm and 780/390 nm, respectively. The increments of scattering intensities (ΔI) are directly proportional to the concentration of Ery in a certain range. The detection limits for Ery are 0.028 μg mL(-1) for RRS method, 0.068 μg mL(-1) for SOS method and 0.11 μg mL(-1) for FDS method, respectively. Among them, the RRS method has the highest sensitivity. Based on the above researches, a new highly sensitive and simple method for the determination of Ery has been developed. In this work, the spectral characteristics of absorption, RRS, SOS and FDS spectra, the optimum conditions of the reaction and influencing factors for the RRS, SOS and FDS intensities were investigated. In addition, the reaction mechanism was discussed.     

Determination of verapamil hydrochloride with 12-tungstophosphoric acid by resonance Rayleigh scattering method coupled to flow injection system

A flow injection analysis (FIA) method coupled to resonance Rayleigh scattering (RRS) detection for the determination of verapamil hydrochloride (VP) was proposed. In pH 1.0 acidic medium, 12-tungstophosphoric acid (TP) reacted with VP to form an ion-association complex, which resulted in a significant enhancement of RRS intensity. The maximum scattering peak was located at 293 nm. RRS intensity was proportional to the concentration of VP in the range of 0.017-13.0 μg mL⁻¹, and the detection limit (3σ) was 5.1 ng mL⁻¹. The proposed method exhibited satisfactory reproducibility with a relative standard derivation (R.S.D.) of 2.1% for 11 successive determinations of 5.0 μg mL⁻¹ VP. Therefore, a novel method for the determination of VP by FIA-RRS was developed. The optimum reaction conditions and the parameters of the FIA operation such as flow rate, injection volume, reactor length, and so on had been optimized in this paper. The present method had been applied to the determination of VP in serum samples and pharmaceuticals with satisfactory results. The maximal sample throughput in the optimized system was 80 h⁻¹.     

硫化镉纳米微粒作探针共振瑞利散射测定某些蒽环类抗癌药物

在pH=5.0—9.0的水溶液中, 硫化镉纳米微粒[(CdS)n]与蒽环类抗生素米托蒽醌(MXT)、 表柔比星(EPI)和柔红霉素(DNR)凭借静电引力及疏水作用力结合, 形成粒径更大的聚集体, 导致共振瑞利散射(RRS)的增强并产生新的RRS光谱, 最大的RRS峰位于292 nm(MXT体系)、 285 nm(DNR体系)和315 nm(EPI体系). 与此同时还观察到二级散射(SOS)和倍频散射(FDS)强度明显提高. 其最大SOS峰位于540 nm(MXT体系)和560 nm(EPI及DNR体系), 而最大的FDS峰分别位于335 nm(MXT体系)、 320 nm(EPI体系)和330 nm(DNR体系). 在一定条件下, 3种散射强度(ΔI)均与药物的浓度成正比, 反应具有高灵敏度, 对于3种药物的检出限在3.6—9.1 ng/mL之间. 其中(CdS)n-MXT体系灵敏度最高, 对MXT的检出限分别为4.1 ng/mL(RRS)、 3.8 ng/mL(SOS)和3.6 ng/mL(FDS). 据此发展了一种用纳米硫化镉作探针, 灵敏、 简便并快速测定蒽环类抗癌药物的共振瑞利散射新方法.     

Resonance Rayleigh scattering spectra, non-linear scattering spectra of tetracaine hydrochloride-erythrosin system and its analytical application

The interaction between erythrosine (ET) and tetracaine hydrochloride (TA) was studied by resonance Rayleigh scattering (RRS), frequency doubling scattering (FDS) and second-order scattering (SOS) combining with absorption spectrum. In a weak acidic medium of Britton-Robinson (BR) buffer solution of pH 4.5, erythrosine reacted with tetracaine hydrochloride to form 1:1 ion-association complex. As a result, the new spectra of RRS, SOS and FDS appeared and their intensities enhanced greatly. The maximum peaks of RRS, SOS and FDS were at 342 nm, 680 nm and 380 nm, respectively. The intensities of the three scattering were directly proportional to the concentration of TA in the range of 0.008-4.2 microg mL(-1) for RRS, 0.027-4.2 microg mL(-1) for SOS and 0.041-4.2 microg mL(-1) for FDS. The methods had very high sensitivities and good selectivities, and the detection limits were 0.003 microg mL(-1) for RRS, 0.008 microg mL(-1) for SOS and 0.012 microg mL(-1) for FDS, respectively. Therefore, a new method was developed to determinate trace amounts of TA. The recovery for the determination of TA in blood serum and urine samples was between 97.0% and 103.8%. In this study, mean polarizability was calculated by AM1 quantum chemistry method. In addition, the reasons for the enhancement of scattering spectra and the energy transfer between absorption, fluorescence and RRS were discussed.     

多菌灵与Pd（II）体系的共振瑞利散射光谱及分析应用

在pH=10.0的Britton-Robinson（BR）缓冲溶液中,多菌灵与Pd(Ⅱ)反应形成1∶1的六元螯合物,导致共振瑞利散射（RRS）、二级散射（SOS）和倍频散射（FDS）显著增强,并产生新的共振瑞利散射光谱,其最大RRS、SOS和FDS波长分别位于309、606和310 nm。 在一定范围内,3种散射增强（ΔIRRS、ΔISOS和ΔIFDS）均与多菌灵的浓度成正比,反应具有较高的灵敏度,对于多菌灵的检出限分别为7.1×10-9 g/mL（RRS）、7.4×10-9 g/mL（SOS）和10.7×10-9 g/mL（FDS）。 据此提出了测定多菌灵的光散射新方法。 以灵敏度最高的RRS法为例,测定了西芹和市售农药中多菌灵的含量,结果与标准方法一致。 文中还对反应机理和散射增强的原因进行了讨论。     

汞(Ⅱ)-邻菲啰啉-刚果红缔合体系的共振瑞利散射和共振非线性散射光谱及分析应用

在pH=9.0的弱碱性环境中,Hg2+与邻菲啰啉(phen)反应形成无色螯合物[Hg(phen)3]2+,再与刚果红(CR)反应,形成三元离子缔合物Hg(phen)3CR,其摩尔比为1∶1。 此时引起共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)光谱显著增强,最大的散射波长分别位于578 nm(RRS法)、612 nm(SOS法)和352 nm(FDS法)。 在一定条件下,散射增强(ΔI)与Hg2+浓度呈良好的线性关系,检出限分别为2.32 μg/L(RRS法)、3.20 μg/L(SOS法)和1.56 μg/L(FDS法),考察了最佳实验条件和影响因素,表明本方法具有良好的选择性,并以RRS法为例研究了共存物质的影响。 据此建立了灵敏度高、选择性好、快速准确测定Hg2+的光散射新方法,该方法用于环境水样中Hg2+的测定取得满意结果。 并对RRS增强的原因和反应机理进行了讨论。