Physicochemical properties, antioxidant activities and in vitro sustained release behaviour of co-encapsulated liposomes as vehicle for vitamin E and β-carotene.

Background: In this study the potential of liposomes as a vitamin E (VE) and β-carotene (βC) delivery system was examined. The co-encapsulated liposomes of βC and VE (L-VE-βC) were prepared and characterized. Their antioxidant properties were evaluated by free radical scavenging activities of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), hydroxyl radical and lipid peroxidation assay.

Interaction of calf thymus DNA and glucose-based gemini cationic surfactants with different spacer length: A spectroscopy and DLS study.

The interactions between calf thymus DNA and a series of glucose-based cationic gemini surfactants 1a-1c with different spacer length, n = 4, 6 and 8, were studied by UV absorption, fluorescence spectroscopy, circular dichroism, FT-IR, dynamic light scattering and zeta potential measurements. The results showed that all the surfactants could interact with DNA efficiently. On addition of increasing concentration of the surfactants, UV absorption hypochromicity with insignificant blue shift were observed, until the DNA signal disappeared.

Interactions with ctDNA of novel sugar-based gemini cationic surfactants.

The interactions between calf thymus DNA, ctDNA, and a series of sugar-based gemini cationic surfactants with different hydrophobic chains were investigated. The surface properties of the cationic gemini surfactants were firstly examined, and then their interactions with DNA and induced condensation of DNA were studied by UV-vis, ethidium bromide exclusion assay, circular dichroism, dynamic light scattering, zeta potential and atomic force microscopy. With the increase of hydrophobic chains of the surfactants, critical micelle concentrations decreased significantly, and the interactions with DNA were remarkably strengthened, with the binding constant up to 1.

Synthesis and biological evaluation of curcumin analogs as β-amyloid imaging agents.

Aim: Detection of β-amyloid (Aβ) plaques in the brain is a very promising biomarker approach for early diagnosis of Alzheimer's disease (AD).

Materials & Methods: A series of curcumin analogs (1,5-diphenyl-1,4-pentadien-3-one derivatives) were synthesized and evaluated. Specific binding to Aβ plaques was demonstrated in vitro using postmortem AD homogenates, and the fluorescent staining and autoradiography in vitro of postmortem AD brain sections were performed.

6-Methoxy-indanone derivatives as potential probes for β-amyloid plaques in Alzheimer's disease.

A series of 6-methoxy indanone derivatives was synthesized and evaluated as potential probes for β-amyloid plaque imaging in Alzheimer's disease (AD). Two derivatives (5d and 5k) displayed significant binding abilities in fluorescent staining experiments using the brain sections of AD patients. Two derivatives showed high binding affinities to β-amyloid aggregates (5j, K = 5.

Homoisoflavonoids as potential imaging agents for β-amyloid plaques in Alzheimer's disease.

A series of homoisoflavonoids [(E)-3-benzylidenechroman-4-ones, 3a-l] as novel potential diagnostic imaging agents targeting β-amyloid (Aβ) plaques in Alzheimer's disease (AD) were synthesized and evaluated. In vitro binding studies using Aβ₁₋₄₀ aggregates with [(125)I]IMPY as the reference ligand showed that these compounds demonstrated high to low binding affinities at the K(i) values ranged from 9.10 to 432.

[Synthesis of benzothiazole derivatives and their binding characteristics with beta-amyloid].

Alzheimer's disease (AD) is a progressive neurodegenerative disease endangering human health seriously. Recent reports have revealed that beta-amyloid aggregates play a key role in the pathogenesis of AD. Thus, targeting the Abeta plaques benzothiazole derivatives were synthesized with the scaffold of the most promising imaging agent PIB ([11C]-6-OH-BTA-1, [11C]-2-(4-(methylamino)phenyl)-6-hydroxybenzothiazole) and C = N as linker to study the binding characteristics with the target protein through surface plasmon resonance (SPR) technique.

Novel indanone derivatives as potential imaging probes for β-amyloid plaques in the brain.

Molecular imaging probes to detect senile plaques (SPs) might help the early diagnosis of Alzheimer's disease (AD). In this study, a novel series of indanone derivatives were synthesized and characterized. In in vitro binding studies, compound 2e exhibited a K(i) value of 16 nM with a human AD brain homogenate.

[Analysis of computational chemistry for the coordination character of Cu2+ and quercetin and kaempferol].

A model based on computational chemistry was established to simulate the coordination character of Cu2+ and flavone compounds. Grid program package in MVD2007 was used in calculating the simulation of the coordination effect between Cu2+ and two flavone compounds, kaempferol and quercetin, both of which have the lowest-energy conformation. Then the potential energy surface of interactional force field and relative binding energy were obtained.

Catalysis and regioselectivity of the aqueous Heck reaction by Pd(0) nanoparticles under ultrasonic irradiation.

An aqueous Heck reaction carried out under ultrasonic irradiation at the ambient temperature (25 degrees C) has been shown in this study to afford high yields of corresponding products. It was found that as a catalyst for the reaction palladium forms nanoparticles in-situ, characterized by transmission electron microscopy (TEM) and X-ray powder diffraction (XRD) analyses, and can be recycled. Furthermore, the Heck reaction under such mild and environmentally friendly conditions offers excellent regioselectivity of para- over ortho-substitution in phenyl iodides especially with electron-donating groups.