Electrospun pH responsive poly (acrylic acid-co- acrylamide) hydrogel nanofibrous mats for drug delivery

In the present study hydrogel nanofibrous mats are prepared through electrospinning of poly (acrylamide-co-acrylic acid) dope solution having polyethylene glycol as cross-linker. The electrospun mats are heat treated at 150 °C to induce esterification crosslinking reaction. The mats are characterized for their structural, morphological and thermal behaviour. The average diameter of hydrogel nanofibers is found to be 275 ± 94.5 nm. The swelling behaviour of nanofibrous mats is evaluated in the phosphate buffer solutions of different pHs in the range of 2 to 8.5 and is found to be highest at neutral pH. The nanofibrous mats are loaded with amoxicillin drug for antimicrobial activity and drug release behaviour. The drug loaded mats form a clear inhibition zone with both Gram-positive bacteria S. aureus and Gram-negative bacteria E. coli in disc diffusion test. Drug is released at all the pHs (2 to 8.5) and maximum release is observed at neutral pH. The kinetics of drug release follows Fickian diffusion (n < 0.5) at tested pH.