Swelling behavior of poly (2-hydroxyethyl methacrylate) copolymer gels

Abstract

Abstract. Hydrogels based on 2-hydroxyethyl methacrylate/dimethyl-aminoethyl methacrylate copolymers were prepared by gamma radiation-inducedco-polymerization at low temperature (−78 • C). The swelling behavior of hydrogels was studied by immersion of the polymer discs in buffered solutions at pH from 2 to 10. The hydration process was followed gravimetrically by measuring the water uptake of the discs as a function of time. The results obtained have shown that the swelling behavior is reversible and depends on the polymer nature. Moreover, polymeric discs exhibited a good stability after repeating cycles of hydration in different buffer solutions. Scanning electron microscopy analysis reveals that hydrogel porosity can be controlled.

Copolymer Involving 2-Hydroxyethyl Methacrylate and 2-Chloroquinyl Methacrylate: Synthesis, Characterization and In Vitro 2-Hydroxychloroquine Delivery Application

“…Indeed, for the drug carrier systems containing a CQMA content equal or superior to 6.22 wt%, the swelling degree at saturation reached a maximum in pH media 3 and 7, then passed by a minimum when the pH medium was 5, while for the CQMA- co -HEMA system containing less CQMA (4.70 wt%), the variation in the swelling rate at equilibrium reached its maximum at pH medium 3, then continuously decreased to reach a minimum at pH 7. Similar results were also obtained by different authors on the swelling capacity of PHEMA-containing amine groups [ 39 , 40 ]. These authors explain the increase in the swelling degree by the positive charge on the amine after protonation in the acidic medium.…”

“…At pH 3, the swelling at equilibrium reached its maximum for all the samples. Similar results were also obtained by Sari et al [ 39 ] in the case of copolymers involving HEMA and N , N -dimethylaminoethyl methacrylate (DMAEMA) monomers. At a high CQMA content (9.68 and 14.82 wt%), the increase in the release dynamic in the neutral pH medium was probably due to the elimination of HCQ from the copolymer through a retroesterification reaction, which was favorable in the medium at pH 7 as shown in Scheme 3 .…”

Assessment of persistent antimicrobial and anti-biofilm activity of p-HEMA hydrogel loaded with rifampicin and cefixime

“…For example, pH-sensitive polymers are polyelectrolytes that have ionizable function groups in their structure that either lose or accept protons and dissociate in response to differences in environmental pH 33 . poly-2-hydroxyethyl methacrylate) (p-HEMA) is a pH-sensitive polymer that contains primary alcohol 34 , with hydrophilic and lipophilic balance, non-toxic, transparent, insoluble 35 , can’t be absorbed by the body 36 , resistant to degradation 37 , has stable mechanical properties 38 . p-HEMA was used in contact lenses, wound dressings, controlled drug release delivery systems, and implants 39 .…”