Study of the absorbent properties of alginic acid

Introduction.Alginicacidis a naturalheteropolysaccharide of brownalgae,consistingofresidues of mannuronicandguluronicacids.It is usedinvariousfields:medicine,foodandpharmaceuticalindustry,cosmetology,ecology,etc. Itsability to bindandretainwatertoformhydrogels is usedin the development of newtechnologiesandmaterials. The structure of thiscompoundisinterestingfrom the point of view of studyingitsabsorbentpropertiesinrelationtosubstances of variouscompositionandstructure.

Material and methods.thestudypresentsvariousmethods for determiningsolutionconcentrationsbasedonphotocolorimetricandspectrophotometricanalysis.Thefollowing compounds wereselectedasexperimentalcompoundsfor the study of absorbentactivity: anions–nitrite,sulfate,iodide;metalcations–calciumandiron(III);protein–glutathione;organicdyes–methyleneblueandmethylorange.

Results.during the study, it turned out thatalginicacidcanabsorb the followingcompounds:nitriteanions-by90.4%,sulfateanions–by71.8%,iodideanions–by28.34%,calciumcations–by58.06%,iron(III)cations–by75.41%,protein–by48.33%,methyleneblue–by 84.22%andmethylorange–by83.72%. The authorssuggestthat the specificabsorbingactivity of alginicacidcan be explained by the followingproperties: alginicacidbindsmetalionsdue to the content of carboxylgroupsand a change in the gelstructureduringswelling; absorption of proteins is caused by electrostaticinteractionwithalginicacidandcompetitionwithmetalcationsforbindingtocarboxylgroups;absorption of anionscanbeassociatedwithelectrostaticinteractionwithcarboxylgroups.

Conclusions. alginic acid has a pronounced absorbent ability in relation to a wide range of compounds of various chemical nature. This feature makes alginic acid a compound suitable for use in filtration and dialysis systems for various purposes, including medical ones.