Pectin from citrus peels (PT, galacturonic acid, ≥ 74%), dopamine hydrochloride (DA, > 98%), acrylic acid (AA, > 99%), ammonium persulfate (APS, > 98%), 1-ethyl-3-(3-(dimethylamino) propyl) carbodiimide hydrochloride (EDC, > 98%), N-hydroxysuccinimide (NHS, > 98%), N,N′-Methylenebis-(acrylamide) (MBAA, > 98%), Ferric nitrate (Fe(NO3)3·9H2O) and natural graphite oxide (GO) were purchased from Sigma Aldrich, USA. All other chemicals were purchased commercially and used without further purification.
