Smart Temperature-Sensitive Injectable Methylcellulose-Based Hydrogels: Design and Optimization for Sustained Drug Release - Supporting Information

1 SUPPORTING INFORMATION Smart Temperature-Sensitive Injectable Methylcellulose-Based Hydrogels: Design and Optimization for Sustained Drug Release Francesca Persano1, Leonardo Lamanna2, Marco Friuli2, Andrea Claudio Stetco3, Amilcare Barca4, Tiziano Verri3, Cosimino Malitesta1, Christian Demitri5,*, Elisabetta Mazzotta1,* 1 Laboratory of Analytical Chemistry, Department of Biological and Environmental Sciences and Technologies (Di.S.Te.B.A.), University of Salento, Lecce (Italy) 2 Department of Engineering for Innovation, Campus Ecotekne, University of Salento, Lecce (Italy) 3 Laboratory of Applied Physiology, Department of Biological and Environmental Sciences and Technologies (Di.S.Te.B.A.), University of Salento, Lecce (Italy) 4 Laboratory of Applied Physiology, Department of Experimental Medicine (Di.Me.S.), University of Salento, Lecce (Italy) 5 Department of Experimental Medicine, University of Salento, Lecce (Italy) Corresponding Authors: [email protected] , [email protected] 2 Figure S1. Molecular structures of the polymers tested in the study: Methylcellulose (MC) (a), Polyethylene glycol (PEG) (b), Chitosan (CH) (c) and Pectin (Pec) (d). 3 Figure S2. Temperature ramps of gel-sol transition of four different hydrogels. Initially the hydrogels were geliation at 37 °C. Samples were cooled from 40 °C to 5 °C at 1 °C/min. Frequency was 1 Hz and shear strain 3%. T gel-sol transition is defined as the crossover of storage G' and loss modulus G''. MC (a), MC/PEG (b), MC/CH (c) and MC/Pec (d). 4 Figure S3. Rheological analysis. Average gelation temperature (a) and average gelation time at 37 °C (b) for MC, MC/PEG and MC/Pec hydrogels. Each point represents the mean ± SD (n = 3). 5 Figure S4. SEM investigation: morphological analysis of hydrogel formulations MC (a, b), MC/PEG (c, d), MC/CH (e, f) and MC/Pec (g, h). Magnification 60X, scale bar 200 µm (left) and magnification 200X, scale bar 100 µm (right). 6 Video S1-S4. Injectability of four different hydrogels. The videos show the injectability of MC (S1), MC/PEG (S2), MC/CH (S3) and MC/Pec (S4) at room temperature, through a G22 needle. For making the visualization easier, the hydrogels are loaded with rhodamine B conferring the typical pink colour.