N phenylglycine

Pregelatinized (cold water swellable) native potato starch (Paselli WA4) was supplied by Avebe and dried at 110 °C overnight prior to use. Oleic acid (90%), 1,1′-carbonyldiimidazole (CDI, ≥97%), chloroform-d3 (CDCl₃, 99.8%), n-phenylglycine (NPG, 97%), and 3-hydroxyflavone (3HF, ≥98%) were purchased from Sigma-Aldrich (St. Louis, MO, USA). Irgacure 184 (>90%) was purchased from BASF(Ludwigshafen, Germany). All organic solvents used for syntheses have a minimum grade of ≥99.7%. All chemicals were used as bought unless stated otherwise.

Polyvinyl alcohol (PVA), N-isopropyl acrylamide (NIPA), N,N-Methylene bisacrylamide (BA), N-Phenylglycine (NPG), Erythrosine B (Er B) and citric acid (CA) were purchased from Sigma-Aldrich, St. Louis, MO, USA. Glycerol was purchased from Fisher Scientific, Hampton, NH, USA, while Fe₃O₄ 20 nm and Fe₂O₃ 20–30 nm MNPs were purchased from GetNanoMaterials, Saint-Cannat, France. All chemicals were used without further modification.
The stock solution of Polyvinyl alcohol (PVA) and Erythrosine B (Er B) sensitising dye was prepared as previously reported [71 (link)]. For PVA solution (10% wt./vol), 10 g of PVA powder was dissolved in 100 mL of deionised (DI) water through magnetic stirring and heating at 75 °C. A dye solution of concentration (0.11% wt./vol) was obtained by dissolving 0.11 g of Er B dye in 100 mL of DI water through magnetic stirring at room temperature.