Luminescent silicon nanocrystals (Si-NCs) surface functionalized with dodecyl groups were exposed to solutions of nitroaromatic compounds including nitrobenzene, nitrotoluene, and dinitrotoluene. It was found that Si-NC luminescence was quenched upon exposure to nitroaromatics via an electron transfer mechanism as indicated by Stern-Volmer analysis. This quenching was exploited and a straightfo...

An acetylene dye rotaxane with alpha-CD has been synthesized using the Heck-Cassar-Sonogashira-Hagihara-type reaction in aqueous solution. Free dye with tetracarboxylic acids is found to be highly sensitive to various metal ions, showing high Stern-Volmer constants, KSV. As CD encapsulation protects and stabilizes the threaded chromophore against an outside quencher, metal-insensitive biologica...

Three new rimantadine Schiff bases (RSBs) were prepared, and then the interaction of RSBs with bovine serum albumin (BSA) was investigated using fluorescence, synchronous fluorescence, UV-vis absorption spectroscopy under physiological conditions. The results showed that the three RSBs effectively quenched the intrinsic fluorescence of BSA via static quenching. Binding constant (K a), number of...

acriflavine (3,6-diaminoacridine) is an anticeptic drug developed in 1912. previous research has focused on investigation of the intercalating features of acriflavine, but little is known about its interaction with proteins. drug-receptor interaction is of major interest in clinical science. the aim of the present study was to evaluate the ability of acriflavine to induce alterations in conform...

Binding to bovine serum albumin of monomeric (vescalagin and pedunculagin) and dimeric ellagitannins (roburin A, oenothein B, and gemin A) was investigated by isothermal titration calorimetry and fluorescence spectroscopy, which indicated two types of binding sites. Stronger and more specific sites exhibited affinity constants, K1, of 10(4)-10(6) M(-1) and stoichiometries, n1, of 2-13 and domin...

Steady state fluorescence measurements have been used for the investigation of interaction between the bovine serum albumin (BSA) and fluorescence probes: 3-hydroxy-2,4- bis[(3-methyl-1,3-benzoxazol-2(3H)-ylidene)methyl]cyclobut-2-en-1-one (SQ6), 3-hydroxy- 2,4-bis[(3-methyl-1,3-benzothiazol-2(3H)-ylidene)methyl]cyclobut-2-en-1-one (SQ7) and 3-hydroxy-2,4-bis[(1,3,3-trimethyl-1,3-dihydro-2H-ind...

Herein, two new iridium(III) complexes, namely Ir2 and Ir3, with a phenyl or triphenylamine (TPA) moiety at the 4-position of ring 2-phenylbenzothiazole, have been synthesized, their emission properties studied systematically compared non-substituted complex Ir1. These three complexes exhibit aggregation-induced (AIE) in H2O/CH3CN. The TPA-substituted Ir3 shows highest AIE activity. All can be ...

Two different metrics are used to assess Forster resonance energy transfer (FRET) between fluorophores in the steady state: (i) acceptor-quenching of donor fluorescence E (also known as transfer efficiency) and (ii) donor-excited acceptor fluorescence F(A) (Dex). While E is still more widely used, F(A) (Dex) has been gaining in popularity for practical reasons among experimentalists who study b...

Mechanistic information on reactions proceeding via photoredox catalysis has enabled rational optimizations of existing and revealed new synthetic pathways. One essential step in any reaction is catalyst quenching photoinduced electron transfer or energy with either a substrate, additive, cocatalyst. Identification the correct quencher using Stern–Volmer studies necessary for mechanistic unders...