Complexation between carrageenan and methylene blue for sensor design

Physically Crosslinked Poly (Vinyl Alcohol)/Kappa-Carrageenan Hydrogels: Structure and Applications

“…The amount of κ-carrageenan leached from the gels during swelling was determined spectrophotometrically, based on the complexation reaction between this polymer and methylene blue (MB) dye in aqueous solutions. According to the procedure adapted from Ling and Heng [34], 100 µL of solution were withdrawn from the liquid swelling media (for the CAR gel, this aliquot of solution was prior diluted 100-fold, from which the same volume was extracted) at determined time intervals and mixed with 1000 µL of 10 mg/L MB and 900 µL of distilled water. The absorbance of the resulting solution was measured at λ max = 559 nm (Spekol 11 spectrophotometer, Carl Zeiss, Jena, Germany, glass cuvettes with a 0.996 cm optical path), and the concentration of carrageenan in the swelling media (c CAR ) was determined based on the prior-constructed calibration curves (sensibility of 5 mg/L CAR, Lambert-Beer law linearity limit: 60 mg/L).…”

Formation of Higher Structural Levels in λ-Carrageenan Induced by the Antimalarial Drug Chloroquine

“…Furthermore, they gained interest in regenerative medicine due to their resemblance to native glycosaminoglycans, serving as cell hydration and signaling agents and as structural scaffolds . The specific interactions of carrageenans with drugs or dye compounds are probed in the methylene blue spectrophotometric assay by monitoring changes in the UV–vis spectrum. − Detailed spectroscopic and release studies of carrageenan and methylene blue or other organic compounds of medical use such as diltiazem HCl and doxazosin were studied as well. − However, the focus of those studies is mainly on the application side, including drug release rates, binding kinetics, as well as mechanical properties. The specific mechanisms of interactions remain largely uncovered.…”

“…The interaction of CQ with single-stranded DNA (ssDNA) was studied by AFM imaging, revealing the formation of complex secondary structures . Little is reported about the interaction of CQ with linear polysaccharides, however. , Studying the interaction between the model polyelectrolyte λ-carrageenan and drugs or dyes on the nanoscale level is of great importance due to their potential use in drug delivery applications and for further fundamental research on polyelectrolyte–drug interactions.…”