Highly Methacrylated Gelatin Bioink for Bone Tissue Engineering

Abstract

Methacrylated gelatin (Gel-MA) is a commonly used biomaterial in bioprinting applications. The Gel-MA synthesis procedure is inadequate and needs to be improved, particularly from the point of optimization and efficacy. We report a significantly faster (by 5 min) and effective method to controllably synthesize Gel-MA using microwave energy (Mw at 1000 W power) with ≥90% degree of methacrylation (DM) even with the use of a very low concentration of methacrylic anhydride (MA). Rheological and mechanical analyses indicated that Gel-MA synthesized by Mw-assisted methacrylation enabled the formation of hydrogels that are more elastic and stronger and have a lower degradation rate (∼27% at 35 days) than Gel-MA synthesized by the conventional method. The viscosity values of the Gel-MA bioink were in the range applicable for use in 3D bioprinters. Additionally, Mw-assisted methacrylated Gel-MA hydrogels that have mechanically superior properties significantly enhanced the viability, attachment, proliferation, alkaline phosphatase (ALP) activity, mineral deposition, and mRNA expression levels of osteogenic genes of MC3T3-E1 preosteoblastic cells.

Design and Synthesis of Chitosan—Gelatin Hybrid Hydrogels for 3D Printable in vitro Models

“…the GE-MF, CH-MF, and PEG-Star-MA solution formed as previously described was transferred into Teflon® molds (15 cm diameter) and left for 3 h at 37°C. Once the Diels-Alder reaction had occurred, the sample was transferred at −20°C for 24 h and then freeze-dried for 48 h to obtain cylindrical samples (Irmak et al, 2019 ). Scanning Electron Microscopy (SEM) was employed to characterize the cross-section of the fibrous dried samples obtained.…”

Overview of Protein‐Based Biopolymers for Biomedical Application

“…Electrospun fibers, porous foams, and hydrogel films of gelatin formulations are widely used for biomedical and therapeutic molecule delivery applications . Methacryloyl group–grafted gelatin known as gelatin methacrylate (GelMA) had been employed for 3D printing and hydrogel and microgel application . Divito et al microfabricated blood vessel using GelMA.…”

A highly efficient microwave-assisted synthesis of an LED-curable methacrylated gelatin for bio applications

“…The complete washing and purication usually last for 1-6 weeks. [20][21][22][23][24][25][33][34][35][36][37][38] Consequently, increasing the MA concentration, time, and temperature are not proper solutions. Up to now, the improvement of the GelMA synthesis and purication procedures is still an underlying challenge for the hydrogel eld.…”

“…According to several publications over the past 30 years, one of the most important methods to increase the chemical reaction rate is the irradiation of microwave (MW). 37,[39][40][41] Based upon the widespread studies, the main advantages of the MW-assisted (MWA) synthesis over the conventional heating methods include the reaction time and side products reduction, uniform and homogeneous reaction, selectiveness, and subsequently higher yields under milder reaction conditions which permit energy and time saving towards the green and sustainable chemistry. [39][40][41][42][43] Irmak et al obtained GelMAs by coupling MA and gelatin under the MW condition and expressed some benets over the conventional method like the signicant reduction of the reaction and puri-cation time as well as the required MA concentration due to the increased reaction efficiency.…”

“…They investigated the effects of varying the MW power and MA concentration on the MD of GelMAs by using 1 H-NMR analysis. 37 Besides, some of the investigations have also prepared GelMAs by using a less known methacrylation reagent, glycidyl methacrylate (GMA) under the conventional heating method. 19,25 To the authors' best knowledge, no study has been performed on the possibility of the GelMA synthesis using GMA under the MW irradiation.…”