Synthesis, characterization, molecular modeling, binding energies of β-cyclodextrin-inclusion complexes of quercetin: Modification of photo physical behavior upon β-CD complexation.

We prepared a naturally occurring flavanoid namely quercetin from tea leaves and analyzed by Absorption, Emission, FT-IR, H, C nmr spectra and ESI-MS analysis. The inclusion behavior of quercetin in cyclodextrins like α-, β-, γ-, per-6-ABCD and mono-6-ABCD cavities were supported such as UV-vis., Emission, FT-IR and ICD spectra and energy minimization studies.

Effect of hydrophobicity and size of the ligands on the intercalative binding interactions of some metallo-surfactants containing π-conjugated systems with yeast tRNA.

The intercalative yeast t-RNA binding behavior of some metallo-surfactant complexes, Co(ip)(TA)](ClO) () and [Co(dpq)(TA)](ClO) () where TA = Tetradecylamine (Myristylamine), ip = imidazo[4,5-f][1,10]phenanthroline and dpq = dipyrido[3,2-d:2'-3'-f]quinoxaline containing π-conjugated systems (both below and above critical micelle concentration) have been investigated by means of absorption spectral titration, competitive binding, circular dichroism, cyclic voltammetry, and viscometry measurements. Absorption spectral titration results implicate yeast tRNA has significant effects on the binding behaviors of two surfactant complexes intercalative mode showed a significant absorption band of hypochromicity with red shift. The intrinsic binding constant values below and above CMC were determined as = 6.

Preferential adsorption of uranium by functional groups of the marine unicellular cyanobacterium BDU130911.

This study reports the surface interaction of the chemically modified marine unicellular cyanobacterium BDU130911 with uranium. The selective functional groups of the control (dead biomass) for binding with uranium in unicellular marine cyanobacteria were identified as carboxyl groups. The adsorption capacity of the biomass in a 1 mM uranium solution was found to be 92% in the control, 85% in the amine-blocked treatments, and 20% in the carboxyl-blocked treatments.

Interaction of digestive enzymes with tunable light emitting quantum dots: a thorough Spectroscopic investigation.

In this article, we have examined the direct spectroscopic and microscopic evidence of efficient quantum dots-α-chymotrypsin (ChT) interaction. The intrinsic fluorescence of digestive enzyme is reduced in the presence of quantum dots through ground-state complex formation. Based on the fluorescence data, quenching rate constant, binding constant, and number of binding sites are calculated under optimized experimental conditions.

"Turn-on-off-on" fluorescence switching of quantum dots-cationic porphyrin nanohybrid: a sensor for DNA.

In this article, we describe a new platform for probing double stranded DNA (dsDNA) by tracing the "on-off-on" fluorescence signals of quantum dots-cationic porphyrin utilizing fluorescence and synchronous fluorescence measurements. Electrostatic interaction between the negatively charged thioglycolic acid capped CdTe quantum dots (CdTe-TGA QDs) and positively charged porphyrin surfaces leads to drastic quenching (turning off) of the donor by an effective electron transfer process. Interestingly, after the addition of calf thymus DNA (CtDNA), the porphyrins peel off from the quantum dot surface and bind to dsDNA, resulting in the restoration of fluorescence intensity of quantum dots (turning on).