Optimized procedure for bioprinting highly concentrated collagen bioinks in tissue engineering applications

Abstract

This study consists of two impacted authors articles attached in extenso that focus on the potential of 3D bioprinting in tissue engineering and regenerative medicine, particularly through the use of highly concentrated collagen bioinks. Collagen, the most common extracellular matrix in tissues, is advantageous due to its natural compatibility with cells and organisms. The first article aims to present a new method for preparing these bioinks without affecting cell viability and proliferation. The presented method involves two successive neutralizations of the prepared hydrogel using bicarbonate buffering mechanisms and pH adjustment. In this process, which includes automated colorimetric pH detection and adjustment, the results showed that the prepared bioink does not negatively affect cell proliferation and viability. The method was validated using bioprinting and subsequent cultivation of collagen hydrogels with incorporated porcine stromal cells. The second article further explores the use of high-concentrated collagen bioinks in bioprinting, acknowledging the challenge of achieving high cell proliferation rates within these hydrogels. To address this, the aim is to develop a culture system where printed collagen bioinks flow freely in the culture medium with continuous medium change, enhancing the nutrient and gas supply and elimination of metabolites of cells. The developed active medium perfusion system significantly improved cell viability and activity in the high-concentrated gel, overcoming a major limitation in using these hydrogels. The study also found that cells remodel the collagen material to their extracellular matrix based on SEM images and geometry analysis. Both articles highlight the promising future of 3D bioprinting with collagen bioinks in advancing tissue engineering.

This study consists of two impacted authors articles attached in extenso that focus on the potential of 3D bioprinting in tissue engineering and regenerative medicine, particularly through the use of highly concentrated collagen bioinks. Collagen, the most common extracellular matrix in tissues, is advantageous due to its natural compatibility with cells and organisms. The first article aims to present a new method for preparing these bioinks without affecting cell viability and proliferation. The presented method involves two successive neutralizations of the prepared hydrogel using bicarbonate buffering mechanisms and pH adjustment. In this process, which includes automated colorimetric pH detection and adjustment, the results showed that the prepared bioink does not negatively affect cell proliferation and viability. The method was validated using bioprinting and subsequent cultivation of collagen hydrogels with incorporated porcine stromal cells. The second article further explores the use of high-concentrated collagen bioinks in bioprinting, acknowledging the challenge of achieving high cell proliferation rates within these hydrogels. To address this, the aim is to develop a culture system where printed collagen bioinks flow freely in the culture medium with continuous medium change, enhancing the nutrient and gas supply and elimination of metabolites of cells. The developed active medium perfusion system significantly improved cell viability and activity in the high-concentrated gel, overcoming a major limitation in using these hydrogels. The study also found that cells remodel the collagen material to their extracellular matrix based on SEM images and geometry analysis. Both articles highlight the promising future of 3D bioprinting with collagen bioinks in advancing tissue engineering.