Loading and release of charged dyes using ultrathin hydrogels.

Langmuir : the ACS journal of surfaces and colloids (2005-08-11)
Takeshi Serizawa, Daisuke Matsukuma, Mitsuru Akashi
ABSTRACT

The anionic dyes methyl orange (MO) and allura red (AR) were used as model drugs to assess the loading and release by layer-by-layer assembled ultrathin hydrogels prepared via the amide formation of poly(acrylic acid-co-N-isopropylacrylamide) with AAc contents of 5, 10, and 15 mol % plus poly(vinylamine hydrochloride). The amount of MO loaded was potentially controlled by changing the dye concentrations, film thickness, and AAc content of the copolymers. The release of AR was controlled by the NaCl concentration and pH. We conclude that the polymeric matrices of ultrathin hydrogels have great potential for the loading and release of charged drugs.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Allura Red AC, Dye content 80 %
Supelco
Allura Red AC, analytical standard