New Polyvinyl Alcohol/Succinoglycan-Based Hydrogels for pH-Responsive Drug Delivery

Abstract

We fabricated new hydrogels using polyvinyl alcohol (PVA) and succinoglycan (SG) directly isolated and obtained from Sinorhizobium meliloti Rm 1021 via the freeze–thaw method. Both the composition of the hydrogels and the freeze–thaw cycles were optimized to maximize the swelling ratio for the preparation of the PVA/SG hydrogels. During the optimization process, the morphology and conformational change in the hydrogel were analyzed by scanning electron microscopy, rheological measurements, and compressive tests. An optimized hydrogel with a maximum swelling ratio of 17.28 g/g was obtained when the composition of PVA to SG was 50:50 (PVA/SG 50/50) and the total number of freeze–thaw cycles was five. The PVA/SG 50/50 hydrogel had the largest pore with 51.24% porosity and the highest cross-over point (28.17%) between the storage modulus (G′) and the loss modulus (G″). The PVA/SG 50/50 hydrogel showed improved thermal stability owing to its interaction with thermally stable SG chains. The improvement in the thermal stability was confirmed by thermogravimetric analysis and differential scanning calorimetry. In addition, the PVA/SG 50/50 hydrogel showed differential drug release according to the corresponding pH under acidic conditions of pH 1.2 and slightly basic conditions of pH 7.4. Furthermore, the cell viability test on the HEK-293 cell line for that hydrogel demonstrated that the PVA/SG 50/50 hydrogel was non-toxic and biocompatible. Therefore, this hydrogel could be a potential scaffold capable of pH-responsive drug delivery for chronic wound dressing applications.

The Preparation and Properties of Amino-Carboxymethyl Chitosan-Based Antibacterial Hydrogel Loaded with ε-Polylysine

“…These results indicated that a sufficient amount of -NH 2 probably leads to a strong Schiff base reaction between the polymer components in the hydrogel, which builds a dense structure of the hydrogel and possesses thermal stability [32]. However, the strongest Schiff base reaction occurred in the ACC 4 /DAS hydrogel, which produced the superfluous Schiff base fractures in the second phase and a decrease in the thermal stability [33]. hydrogel, which produced the superfluous Schiff base fractures in the second phase and a decrease in the thermal stability [33].…”

“…However, the strongest Schiff base reaction occurred in the ACC 4 /DAS hydrogel, which produced the superfluous Schiff base fractures in the second phase and a decrease in the thermal stability [33]. hydrogel, which produced the superfluous Schiff base fractures in the second phase and a decrease in the thermal stability [33].…”

“…Foods 2023, 12, x FOR PEER REVIEW 9 of 13 hydrogel, which produced the superfluous Schiff base fractures in the second phase and a decrease in the thermal stability [33].…”

Cryostructuring of Polymeric Systems: 67 Properties and Microstructure of Poly(Vinyl Alcohol) Cryogels Formed in the Presence of Phenol or Bis-Phenols Introduced into the Aqueous Polymeric Solutions Prior to Their Freeze–Thaw Processing

“…Such physical (non-covalent) PVACGs are of a high practical interest in various fields, especially as materials for biomedical applications [ 4 , 5 , 16 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ]. With regard to medical aspects, the use of cryogels based on PVA itself [ 19 , 20 , 22 , 28 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ] and its blends with other (both synthetic and natural) polymers [ 18 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 ] and composite cryogels that contain entrapped functional disperse fillers [ …”

“…Such physical (non-covalent) PVACGs are of a high practical interest in various fields, especially as materials for biomedical applications [4,5,16,[18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33]. With regard to medical aspects, the use of cryogels based on PVA itself [19,20,22,28,[32][33][34][35][36][37][38][39][40][41][42][43] and its blends with other (both synthetic and natural) polymers [18,[44][45][46][47][48][49][50][51][52][53][54][55][56][57]…”