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Resonance Rayleigh Scattering (resonance + rayleigh_scattering)
Selected AbstractsSmall-Molecule-Directed Assembly: A Gold Nanoparticle-Based Strategy for Screening of Homo-Adenine DNA Duplex Binders,ADVANCED MATERIALS, Issue 4 2008G. Song By using AuNP-modified homo-adenine DNA conjugate as a model system, simple colorimetric and resonance Rayleigh scattering assays have been developed for screening small molecules that trigger the formation of the non-Watson,Crick homo-adenine duplexes. The assay presented here is more simplified in format as it involves only one type of ssDNA modified Au-NP, and can be easily adapted to high-throughput screening. [source] Resonance Rayleigh scattering method for the determination of chitosan with some anionic surfactantsLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 3 2008Yu-Wei Wang Abstract In weak acidic buffer medium, chitosan binding with an anionic surfactant, such as sodium dodecyl benzene sulphonate (SDBS), sodium lauryl sulphate (SLS) or sodium dodecyl sulphonate (SDS), can result in a significant enhancement of resonance Rayleigh scattering (RRS) intensity. The results showed that under optimum conditions the enhanced RRS intensity is proportional to the concentration of chitosan in the range 0.10,20.0 µg/mL for SDBS, 0.27,15.0 µg/mL for SLS and 0.20,15.0 µg/mL for SDS. Among these, the sensitivity of SDBS is the highest and its detection limit for chitosan is 29 ng/mL, while those of SLS and SDS are 83 and 61 ng/mL, respectively. The method has good selectivity and was applied to the determination of trace amounts of chitosan in practical samples with satisfactory results. Therefore, a simple and convenient method with high sensitivity and selectivity for the determination of chitosan was established. Copyright © 2008 John Wiley & Sons, Ltd. [source] Ultrahighly Sensitive Homogeneous Detection of DNA and MicroRNA by Using Single-Silver-Nanoparticle CountingCHEMISTRY - A EUROPEAN JOURNAL, Issue 3 2010Fagong Xu Dr. Abstract DNA and RNA analysis is of high importance for clinical diagnoses, forensic analysis, and basic studies in the biological and biomedical fields. In this paper, we report the ultrahighly sensitive homogeneous detection of DNA and microRNA by using a novel single-silver-nanoparticle counting (SSNPC) technique. The principle of SSNPC is based on the photon-burst counting of single silver nanoparticles (Ag NPs) in a highly focused laser beam (about 0.5,fL detection volume) due to Brownian motion and the strong resonance Rayleigh scattering of single Ag NPs. We first investigated the performance of the SSNPC system and then developed an ultrasensitive homogeneous detection method for DNA and microRNA based on this single-nanoparticle technique. Sandwich nucleic acid hybridization models were utilized in the assays. In the hybridization process, when two Ag-NP,oligonucleotide conjugates were mixed in a sample containing DNA (or microRNA) targets, the binding of the targets caused the Ag NPs to form dimers (or oligomers), which led to a reduction in the photon-burst counts. The SSNPC method was used to measure the change in the photon-burst counts. The relationship between the change of the photon-burst counts and the target concentration showed a good linearity. This method was used for the assay of sequence-specific DNA fragments and microRNAs. The detection limits were at about the 1,fM level, which is 2,5 orders of magnitude more sensitive than current homogeneous methods. [source] Effects of the Interaction of Rifamycin SV with Serum Albumins on the Resonance Rayleigh Scattering Spectra and Their Analytical ApplicationCHINESE JOURNAL OF CHEMISTRY, Issue 5 2008Ji-Dong YANG Abstract In pH 4.5,4.8 Britton-Robinson buffer solution, rifamycin SV (i.e. rifamycin sodium) can react with serum albumin such as human serum albumin (HSA) and bovine serum albumin (BSA) to form macromolecular complexes by electrostatic attraction and hydrophobic force. As a result, the resonance Rayleigh scattering (RRS) of the drug was enhanced remarkably and the RRS peaks were at 374 and 552 nm. The enhancement of RRS (,I) is directly proportional to the concentration of HSA or BSA. The linear ranges and the detection limits are 0.03,6.0 µg/mL and 9.0 ng/mL for HSA, and 0.01,8.0 µg/mL and 2.0 ng/mL for BSA, respectively. In this work, a sensitive, selective, simple and fast method for the determination of trace amounts of serum albumin by RRS technique has been developed, which was applied to the determination of serum albumin in the synthesized samples and human urine samples with satisfactory results. [source] Determination of Potassium Ferrocyanide in Foods by Resonance Rayleigh Scattering Method with Double-Charged Triaminotriphenylmethane DyesCHINESE JOURNAL OF CHEMISTRY, Issue 7 2007Yong-Li Li Abstract In pH 1.0 acidic medium, double-charged triaminotriphenylmethane dyes such as methyl green (MeG) and iodine green (IG) react with potassium ferrocyanide to form 2:1 ion-association complexes by virtue of electrostatic forces and hydrophobic interaction. It results in the change of absorption and the great enhancement of resonance Rayleigh scattering (RRS) and the appearance of new RRS spectra. Two systems have similar spectral characteristics and their maximum RRS wavelengths are all located at 276 nm and smaller peaks are located at 332 and 457 nm, respectively. The intensity of RRS is directly proportional to the concentration of [Fe(CN)6]4, in the range of 0.03,5.7 µg·mL,1 (MeG system) or 0.04,5.9 µg·mL,1 (IG system). The RRS method has high sensitivity and the detection limit (3,) for potassium ferrocyanide is 9.3 ng·mL,1 (MeG system) or 11.2 ng·mL,1 (IG system). The optimum conditions, influencing factors and effects of foreign substances are investigated. The method also has a good selectivity. A sensitive, rapid and simple RRS method for the determination of potassium ferrocyanide in salinized food and table salt has been developed. [source] Resonance Rayleigh Scattering Spectra of Thorium (IV)-bisazo Dye of Chromotropic Acid-protein Systems and Their Analytical ApplicationsCHINESE JOURNAL OF CHEMISTRY, Issue 1 2003U Fan Abstract In acidic medium, thorium (IV) can react with a bisazo dye of chromotropic adds such as arsenazo HI (AA in), arsenazo M (AA M), chlorophosphonazo III (CPA III) and chlorosulphonphenol S (CSP S) to form an anionic chelate which further interacts with some proteins to produce a complex. This results in a significant enhancement of intensity of the resonance Rayleigh scattering (RRS) and the appearance of a new RRS spectrum. There are a few obvious RRS peaks in the range of 400,470 nm and the most intensive peak of them is located at 470 nm. The intensity of RRS is directly proportional to the concentration of protein in the range of 0,l.ö,g-mL,1 for Th(IV)-CPA III system, 0,2.8 ,g-mL,1 for Th(IV)-AA M system, 0,2.0 ,g·mL,1 for Th(IV)-AA III system and 0,0.28 ,g·mL,1 for Th(IV)-CSP S system, respectively. The detection limits for BSA (3s,) are 10.7 ng·mL,1 for Th (IV)-CPA III, 6.3 ng·mL,1 for Th(IV)-CSP S, 13.6 ng·mL,1 for Th(IV)-AA III and 22.1 ng·mL,1 for Th(IV)-AA M, respectively. This new RRS method has high sensitivity and fairly good selectivity and can be applied to the direct determination of proteins in human serum with satisfactory results. [source] | ||||||||||