A new class of dynamic hydrogels made through Schiff base bonds based on gelatin (type A and B) and polyethylene glycol dibenzaldehyde (diBA‐PEG, 2000 and 4000 g mol−1) is developed. Hydrogels form in situ by mixing aqueous solutions of gelatin and diBA‐PEG at a carefully adjusted pH. Compression test shows that the samples based on gelatin A are able to withstand at least ten cyclic loading/unloading without crack formation and significant permanent deformation. Self‐healing behavior of the hydrogel is proved by rheological measurements and also visual method. This hydrogel is proven to be injectable and nontoxic. Performance of the hydrogel in loading and delivery of clindamycin hydrochloride, as an antibacterial model drug, is evaluated against Staphylococcus aureus via antibacterial activity test. In vitro release of clindamycin hydrochloride is studied through an innovative method and it becomes clear that the release of clindamycin hydrochloride from this hydrogel follows a zero‐order kinetics.

linkages formed between aldehyde and amine functional groups offer unique properties including self-healing and injectability in the so-called dynamic hydrogels. [1][2][3][4][5] Hence, Schiff base-based dynamic hydrogels have found application in regenerative medicine, drug delivery, [6,7] wound dressing. [8,9] Cell delivery for regenerative medicine is one of the marvelous applications of dynamic hydrogels based on natural polymers which are addressed in recent scientific reports. For example, chitosan crosslinked using polyethylene glycol dibenzaldehyde through Schiff base linkages were found to be an injectable and self-healing hydrogel. Such prepared hydrogels have been used as a cell delivery vehicle for encapsulation of neural stem cells for promoting nerve regeneration. [3] Another self-healing/injectable hydrogel was reported as a cell carrier for cardiac cell therapy by Schiff base linkages between chitosan chains and polyethylene glycol dibenzaldehyde. [10] As another example, a self-healing and injectable hydrogel cell carrier for myoblast cell therapy was reported prepared by Schiff base linkages between N-carboxyethyl chitosan and dextran-graft-aniline tetramer-graft-4-formylbenzoic acid. [11] Such studies have been focused on the formation of Schiff base linkages via benzaldehyde derivatives for crosslinking chitosan as the amine sharing part and the obtained hydrogels support both injectability and self-healing characteristics as the cell delivery systems.On the other hand, there are some reports on fabrication of injectable and self-healing dynamic hydrogels based on Schiff base linkages by aliphatic aldehyde sharing parts for cell delivery applications. For example, an injectable and self-healing hydrogel was prepared via formation of Schiff base linkages between N-succinyl-chitosan and chondroitin sulfate multiple aldehyde. The reported hydrogel was used for encapsulation of Hela cells. [12] Also, a hydrogel with mentioned characteristics was reported which was fabricated by the formation of Schiff base linkages between N-carboxyethyl chitosan and oxidized sodium alginate and was used as a cell carrier for neural stem cells. [13] Moreover, another injectable and self-healing hydrogel Despite excellent processing and biological properties of gelatin for use as a cell carrier, none of the gelatin-based hydrogel cell carriers reported to date offer all characteristics including quick formation, injectability, self-healing, and durability, which are simultaneously required for an ideal system. Here, a gelatin-based hydrogel with dynamic Schiff base linkages, so-called "dynamic hydrogel," as an injectable cell carrier consisting of gelatin and amylopectin multiple aldehyde (AMPA), with all the required characteristics is reported. Biocompatibility and osteoinductivity of the hydrogel are verified through the culture of human bone marrow-derived mesenchymal stem cells (hBMSCs). As live/dead results show, hBMSCs are alive and highly viable ≈85-90% within the hydrogel after 5 days. According to bromodeo...

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Polyethersulfone (PES) microfiltration membranes were fabricated by a combined vapor‐induced phase separation and wet phase separation method. The effect of different non‐solvent additives in casting solution, ie, acetone, diethylene glycol, and triethylene glycol (TEG) was investigated on the membrane morphology and performance. Scanning electron microscopy images showed that the membrane containing TEG additive had a skinless symmetric structure with well interconnected pores. The permeability of the PES/PVP/TEG membranes increased by decreasing PES and TEG and increasing PVP concentration. Bacteria removal performance of the prepared membranes was investigated by the filtration of E. coli suspension. The membrane made from casting solution containing 15 wt.% PES, 16 wt.% PVP, and 20wt.% TEG showed a pure water flux of ~ 5370 L/m2 h at low transmembrane pressure of 10 psi and 100% bacteria removal efficiency. The results of in vitro cytotoxicity test and cell viability assay showed non‐toxic nature of the prepared membranes.