Construction of a Fluorescence-Based Logic Gate Seeing the Effect of Perchlorate Ions on Hemicyanine Dye-β-Cyclodextrin Complexes to Certify Safe Drinking Water.

Perchlorate ions (ClO ) are prevalent contaminants in the surface, and drinking water that disrupt thyroid function by competitively inhibiting the sodium-iodide symporter (NIS), posing significant health risks. Here, fluorescence-based logic gates have been constructed by leveraging the binding interactions between a hemicyanine dye, 4-[4-(dimethylamino)-styryl]-1-docosylpyridinium bromide (DASPC22) and β-cyclodextrin (β-CD) that could be useful to know whether ClO ions in water are within the toxicity range or not. In aqueous media, DASPC22 forms nonfluorescent H-aggregates, but fluorescence is enhanced upon forming host-guest inclusion complexes with β-CD.

ct-DNA compaction by nanoparticles formed by silica and gemini surfactants having hydroxyl group substituted spacers: In vitro, in vivo, and ex vivo gene uptake to cancer cells.

Hybrid nanoparticles formed by Silica (SiO) coated with cationic gemini surfactants with variable hydroxyl group substituted spacers, 12-4(OH)-12,2Br and 12-4(OH)-12,2Br have shown a great extent of compaction of calf thymus DNA (ct-DNA) compared to conventional counterpart cationic surfactant, dodecyl trimethylammonium bromide (DTAB). Study shows not only the hydrophobicity of the spacer but also the hydrogen bonding interactions between the hydroxyl group substituted spacer and DNA have a great role in DNA compaction. 12-4(OH)-12,2Br is more efficient in compacting ct-DNA compared to 12-4(OH)-12,2Br due to the stronger binding of the former with ct-DNA than the latter.

Compaction of Calf Thymus DNA by a Potential One-Head-Two-Tail Surfactant: Properties of Nanomaterials and Biological Testing for Gene Delivery.

A one-head-two-tail cationic surfactant, Dilauryldimethylammonium bromide (DDAB) has shown a great extent of calf thymus DNA (ct-DNA) compaction being adsorbed on the surfaces of negatively charged SiO nanoparticles (NPs). DDAB molecules show high adsorption efficiency and induce many positive surface charges per-unit surface area of the SiO NPs compared to cationic Gemini (12-6-12) and conventional (DTAB) surfactants in an aqueous medium at pH 7.4, as evident from zeta potential and EDAX data.

Role of Gemini Surfactants with Variable Spacers and SiO Nanoparticles in ct-DNA Compaction and Applications toward / Gene Delivery.

Compaction of calf thymus DNA (ct-DNA) by two cationic gemini surfactants, 12-4-12 and 12-8-12, in the absence and presence of negatively charged SiO nanoparticles (NPs) (∼100 nm) has been explored using various techniques. 12-8-12 having a longer hydrophobic spacer induces a greater extent of ct-DNA compaction than 12-4-12, which becomes more efficient with SiO NPs. While 50% ct-DNA compaction in the presence of SiO NPs occurs at ∼77 nM of 12-8-12 and ∼130 nM of 12-4-12, but a conventional counterpart surfactant, DTAB, does it at its concentration as high as ∼7 μM.

Refolding of denatured gold nanoparticles-conjugated bovine serum albumin through formation of catanions between gemini surfactant and sodium dodecyl sulphate.

The present work elucidates binding interactions of sodium dodecyl sulphate (SDS) with the conjugated gold nanoparticles (AuNPs)-bovine serum albumin (BSA), unfolded by each of two gemini surfactants, 1,4-bis(dodecyl-,-dimethylammonium bromide)-butane (12-4-12,2Br) or 1,8-bis(dodecyl-,-dimethylammonium bromide)-octane (12-8-12,2Br). Initially, at a low concentration of SDS there is a relaxation of bioconjugates from their compressed form due to the formation of catanions between SDS and gemini surfactants. On moving towards higher concentrations of SDS, these relaxed unfolded bioconjugates renature by removal of residual bound gemini surfactants.