Methylcellulose Based Thermally Reversible Hydrogel System for Tissue Engineering Applications

Abstract

The thermoresponsive behavior of a Methylcellulose (MC) polymer was systematically investigated to determine its usability in constructing MC based hydrogel systems in cell sheet engineering applications. Solution-gel analyses were made to study the effects of polymer concentration, molecular weight and dissolved salts on the gelation of three commercially available MCs using differential scanning calorimeter and rheology. For investigation of the hydrogel stability and fluid uptake capacity, swelling and degradation experiments were performed with the hydrogel system exposed to cell culture solutions at incubation temperature for several days. From these experiments, the optimal composition of MC-water-salt that was able to produce stable hydrogels at or above 32 °C, was found to be 12% to 16% of MC (Mol. wt. of 15,000) in water with 0.5× PBS (~150mOsm). This stable hydrogel system was then evaluated for a week for its efficacy to support the adhesion and growth of specific cells in culture; in our case the stromal/stem cells derived from human adipose tissue derived stem cells (ASCs). The results indicated that the addition (evenly spread) of ~200 µL of 2 mg/mL bovine collagen type -I (pH adjusted to 7.5) over the MC hydrogel surface at 37 °C is required to improve the ASC adhesion and proliferation. Upon confluence, a continuous monolayer ASC sheet was formed on the surface of the hydrogel system and an intact cell sheet with preserved cell–cell and cell–extracellular matrix was spontaneously and gradually detached when the grown cell sheet was removed from the incubator and exposed to room temperature (~30 °C) within minutes.

Cellulose-Derivatives-Based Hydrogels as Vehicles for Dermal and Transdermal Drug Delivery

“…Although the gelation of MC has been extensively studied by various analytical techniques (NMR, differential scanning calorimetry, IR attenuated total reflectance spectroscopy, small-angle neutron scattering, static and dynamic light scattering, and rheology) and the researchers have proposed different gelation mechanisms, the specific molecular interactions that govern this process is still unclear. However, the results of various studies, which were in good agreement one with another, indicated several factors and/or phenomena which play an important role in the gelation of MC [24,[51][52][53][54][55][56][57][58][59][60][61][62][63][64]:…”

Living Cell Factories ‐ Electrosprayed Microcapsules and Microcarriers for Minimally Invasive Delivery

“…The precise gelation mechanism needs to be considered and adapted accordingly when electrospraying with different materials. For example, pectin responds to pH depending on its origin [39] , methylcellulose responds to temperature [40] , and alginate is UV responsive as demonstrated by Guo et al who showed an increasing porosity in 3-D alginate scaffolds when exposed to ultrasound leading to improved growth of chondrocytes [41] . Thus, microcapsule and microcarrier preparation can vary depending on material and desired physical parameters for specific applications.…”

Bioprinting of Organs and Tissues

“…Проводимые за рубежом и в России разработки матриксов (скаффолдов) как носителей кле-ток при трансплантации можно разбить на две большие группы: создание матриксов из биостабильных матери-алов (биостабильные синтетические полимеры, спла-вы, керамика) и из биодеградируемых материалов ис-кусственного или природного происхождения [35] Наиболее часто в биопечати в качестве скаффол-дов используют гидрогели, в состав которых могут вхо-дить следующие вещества: альгиновая кислота или альгинат [36,37], хитозан [38], желатин [39], гиалуроно-вая кислота [40,41], агароза [42], коллаген [43,44], плю-роник [45], матригель [46], метилцеллюлоза [47,48], метилцеллюлоза [49], фибрин [50].…”