Cytotoxicity and bioadhesive properties of poly-N-isopropylacrylamide hydrogel

Abstract

Several hydrogel surfaces present properties that simulate the mechanical and physicochemical features of extracellular matrix (ECM), providing a platform that mimic the native cellular milieus. Poly- N -isopropylacrylamide (PNIPAM) hydrogels are receiving attention in biomedical field due to their thermosensibility and soft texture. However, more extensive biocompatibility and cellular interactions studies with cell lines are needed. Therefore, the aim of this study is focus on evaluating the biocompatibility of PNIPAM through cytotoxicity, genotoxicity, and proliferation tests in murine preadipose cells (3T3-L1), human embryonic kidney cells (HEK293) and human carcinoma-derived cells (A549) in presence of hydrogel surfaces. Bioadhesive capacity above PNIPAM surfaces was also analyzed. MTT and neutral red uptake assays shown non-cytotoxic effect of PNIPAM in the studied cell lines. Genotoxicity was evaluated by the single-cell gel electrophoresis assay, where DNA damages were not detected. [ 3 H]-thymidine staining allowed to corroborate that cell proliferation had progressed correctly. Adopted morphologies for each cell line over PNIPAM were similar to cell growing observed on polystyrene, indicating that the surfaces favor the cell attachment during 5 days' culture. The good biocompatibility of PNIPAM surfaces make it an interesting scaffold with clinical potential in tissue regeneration engineering, and a possible adipose and kidney tissue-engineered construct.

Synthesis and Evaluation of a Thermoresponsive Degradable Chitosan-Grafted PNIPAAm Hydrogel as a “Smart” Gene Delivery System

“…The NIPAAm monomer has shown a concentration-dependent cytotoxicity with endothelial, epithelial, smooth muscle, and fibroblasts [83]. However, the polymerization of NIPAAm resulted in production of a biocompatible PNIPAAm hydrogel [84][85][86][87]. During synthesis of the Cs-g-PNIPAAm hydrogel, any unpolymerized NIPAAm chains were removed during a five-day dialysis purification step using a 10-kDa dialysis membrane to ensure safety.…”

Bioresorbable Materials on the Rise: From Electronic Components and Physical Sensors to In Vivo Monitoring Systems

“…However, none of these approaches has been evaluated in vivo, either in terms of specificity and reliability or biocompatibility. An interesting strategy to be explored is the use of thermoresponsive polymers that change molecular configuration (and hence solubility) when cooled below a tunable threshold temperature (namely, lower critical solution temperature (LCST)), e.g., poly( N ‐isopropylacrylamide) (PNIPAAM), which has shown good biocompatibility …”

Mechanical and physicochemical behavior of a 3D hydrogel scaffold during cell growth and proliferation

“…In addition, the cytotoxicity of PNIPAM and bioadhesive properties of murine preadipose cells (3T3-L1), human embryonic kidney cells (HEK293), and human carcinoma-derived cells (A549) in contact with these surfaces were recently studied. 16 In many cases, swollen hydrogels can be extremely weak materials and exhibit poor mechanical properties, 17 thus limiting their utilization as three-dimensional matrices. 18 However, there are several strategies to increase the material elastic modulus 19 including semi-interpenetrated systems, 20 polymeric nanocomposite formation, 21,22 co-polymerization, 23 modication of the monomer/crosslinker ratio, 24 and the incorporation of rodlike pores.…”