The Ms of magnetite was significantly increased (55.5 emu/g) as compared to magnetite nanoparticles modified by surfactants with oxygen ligands, indicating their potential applications as drug-delivery systems (DDSs) where high saturated magnetization (Ms) is preferred. Besides, the amount of CS layer of CS-MNPs was approx. 24 wt%, which makes the synthesized CS-MNPs highly biocompatible as no acute adverse effect of the viability on MG-63 cells was observed at doses up to 0.2 mg/ml. Macropinocytosis is the main endocytic mechanism of MG-63 cells internalize CS-MNPs, which might avoid
lysosomal degradation of the CS-MNPs. The synthesized CS-MNPs have see more potential applications in the fields of targeted drug delivery, separation for purification and immunoassay and magnetic resonance imaging. (C) Koninklijke Brill NV, Leiden, 2012″
“Purpose To assess tight junction integrity in cultured human foetal retinal pigment epithelium (RPE) after exposure to clinically relevant indocyanine green (ICG) concentrations. Methods Human foetal RPE was cultured with the Hu & Bok method. The apical compartments of well-differentiated cultures were exposed to 0.125, 0.05 and 0.025mg/ml ICG with or without 10-min illumination. Vehicle and trypsin/EDTA or EDTA alone served
as controls. Three minutes was chosen to mimic surgical exposure time, while 3h was used for toxicity assays, with Selleck C59 subsequent wash
out. Cell-cell junctions were studied before and after exposure by phase contrast microscopy and immunofluorescence (ZO-1). Blood-retinal barrier function was measured through transepithelial electrical resistance (TER). Results At 6-8weeks postconfluence, RPE had grown into pigmented hexagonal monolayers with stable TER (435-1227 omega*cm(2)). After 3min ICG exposure, cell morphology remained unchanged, with patchy cell-cell dissociation in positive controls. https://www.selleckchem.com/products/prt062607-p505-15-hcl.html A continuous ZO-1 signal was detected in ICG groups, whereas trypsin controls showed patchy loss of the tight junction stain. TER had dropped at 1.5h after 3min exposure to 22.8 +/- 3.1%, compared with 10.2 +/- 3.9% in positive controls. Surgical light illumination did not affect TER. After 3h exposure to 0.05mg/ml ICG, TER decreased to 58.1 +/- 8.3%, while vehicle controls maintained similar levels as prior to exposure (92.7 +/- 2.4%). TER recovered in all ICG groups to prior levels within 3days. Conclusion Indocyanine green (ICG) exposure induced a transient decrease in transepithelial electrical resistance, despite unaltered tight junction structure.”
“The fluorescence quenching of quinidine in acidified aqueous solution by various halides (CI-, Brand I-) was studied using steady state and time resolved fluorescence techniques. The quenching process was characterized by Stern-Volmer (S-V) plots.