2 hydroxy 40 2 hydroxyethoxy 2 methylpropiophenone

Polydimethylsiloxane
(PDMS) (SYLGARD 184) was purchased from Dow Corning Corp. (Midland,
USA). Poly(vinyl alcohol) (PVA, Mw 31,000–50,000), poly(dl-lactide-co-glycolic) acid (PLGA, lactide:glycolide 50:50,
Mw 38,000–54,000), poly(ethylene glycol) diacrylate (Mn 750)
(PEG-DA), and 2-hydroxy-40-(2-hydroxyethoxy)-2-methylpropiophenone
(photo-initiator) were purchased from Sigma-Aldrich (Missouri, USA).
DTXL was purchased from Alfa Aesar (Massachusetts, USA). 4-(Dimethyl-amino)pyridine
(DMAP) (99%) was purchased from Sigma-Aldrich. Dichloromethane anhydrous
≥99.8%, which contains 40–150 ppm amylene as stabilizer,
was purchased from Sigma-Aldrich. Amine PEG 550 Da and 1000 Da were
purchased from Creative PEGWorks.

Hydrogels were prepared using acrylamide (acrylamide, AAm, Sigma) and methylenebisacrylamide (N,N′-methylenebisacrylamide, MBA, Sigma) as monomers. The total concentration of AAm was fixed at 20% (w/v) and prepared by adjusting the concentration of MBA between 0.02% to 0.3% (w/v). An initiator, Irgacure2959 (2-hydroxy-40-(2-hydroxyethoxy)-2-methylpropiophenone, Sigma), was added to reach a final concentration of 0.2% (w/v). The hydrogels were formed by exposure to ultraviolet (UV) light (365 nm, VILBER LOURMAT, 4W) for 10 min. Subsequently, the gels were punched into 8 mm diameter disks and incubated in deionized (DI) water until fully swollen before characterization. The resulting hydrogels demonstrated tunable properties, showcasing the versatility of this synthesis approach for creating hydrogels with a range of mechanical and swelling characteristics suitable for diverse applications.