5-Amino-2-naphthalenesulfonic acid

Anti-angiogenic activity of heparin-like polysulfonated polymeric drugs in 3D human cell culture.[Pubmed:20674006]

Biomaterials. 2010 Nov;31(31):7863-72.

The activity of new anti-angiogenic polymeric drugs was tested in a 3D endothelial cell culture system applied as a model of angiogenesis. The assay was performed in a highly reproducible fibrin matrix that supported endothelial cell attachment, proliferation, migration, and formation of capillary-like structures. Active growth factors (FGF and/or VEGF) were added to the medium to induce the formation of blood vessel-like structures, and the effect of the active polymers was then tested by a semi-quantitative immunostaining protocol and visualized by laser-scanning confocal microscopy. The synthetic heparin-like macromolecules that were tested for their anti-angiogenic efficacy were previously characterized in terms of their anti-proliferative activity in 2D tissue culture. Two different anti-angiogenic monomers, a methacrylic derivative of 5-Amino-2-naphthalenesulfonic acid (MANSA) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS), were copolymerized with a hydrophilic monomer (vinyl pyrrolidone, VP) or a hydrophobic monomer (butyl acrylate, BA), giving rise to different copolymeric systems with controlled microstructure and supramolecular organization. Both copolymeric systems have demonstrated a composition-dependent anti-mitogenic effect in "2D in vitro" cell culture experiments using aFGF as pro-angiogenic growth factor and BALB/c 3T3 fibroblast as cell model, as was shown in a previous publication. These 3D experiments provide evidence for the strong and specific modulation of angiogenesis by these systems. The 3D experiments constitute an improvement over 2D in vitro experiments and in vivo experiments with angiogenic drugs and may help to reduce the number of animal experiments.

An analytical system for the characterization of highly heterogeneous mixtures of N-linked oligosaccharides.[Pubmed:19281790]

Anal Biochem. 2009 Jun 1;389(1):40-51.

A novel system for characterizing complex N-linked oligosaccharide mixtures that uses a combination of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), capillary electrophoresis (CE), and high-performance liquid chromatography (HPLC) has been developed. In this study, oligosaccharides released from recombinant TNK-tPA (tissue plasminogen activator) were derivatized with 5-Amino-2-naphthalenesulfonic acid (ANSA). The negative charge imparted by the ANSA label facilitated the analysis of the oligosaccharides by MALDI-TOF MS by allowing the observation of both neutral and sialylated oligosaccharides in a single negative ion mode spectrum. Labeling with ANSA was also determined to be advantageous in the characterization of oligosaccharides by both HPLC and CE. The ANSA label was demonstrated to provide superior resolution over the commonly used label 8-aminopyrene-1,3,6-trisulfonic acid (APTS) in both the CE and HPLC analysis of oligosaccharides. To date, no other labels that enable the analysis of complex oligosaccharide mixtures in a single mass spectral mode, while also enabling high-resolution chromatographic and electrophoretic separation of the oligosaccharides, have been reported. By integrating the structural information obtained by MALDI-TOF MS analysis with the ability of CE and HPLC to discriminate between structural isomers, the complete characterization of complex oligosaccharide mixtures is possible.

Poly(3,4-ethylenedioxythiophene-co-(5-amino-2-naphthalenesulfonic acid)) (PEDOT-PANS) film modified glassy carbon electrode for selective detection of dopamine in the presence of ascorbic acid and uric acid.[Pubmed:17616245]

Anal Chim Acta. 2007 Jul 16;596(1):92-8.

Poly(3,4-ethylenedioxythiophene-co-(5-Amino-2-naphthalenesulfonic acid)) (PEDOT-PANS) film modified glassy carbon electrode was prepared by electrochemical polymerization technique. The properties of modified electrode was studied. It was found that the electrochemical properties of modified electrode was very much dependent on the experimental conditions, such as monomer oxidation potential and pH. The modified electrode surface was characterized by scanning electron microscopy (SEM). The PEDOT-PANS film modified electrode shows electrocatalytic activity toward oxidation of dopamine (DA) in acetate buffer solution (pH 5.0) and results in a marked enhancement of the current response. The linear sweep voltammetric (LSV) peak heights are linear with DA concentration from 2x10(-6) to 1x10(-5) M. The detection limit is 5x10(-7) M. More over, the interferences of ascorbic acid (AA) and uric acid (UA) were effectively diminished. This work provides a simple and easy approach for selective determination of dopamine in the presence of ascorbic acid and uric acid.