Perfusion of the 3D printed construct after removal of the sacrificial ink (8x8x6mm)..

<p>We used silated-hydroxypropylmethylcellulose (Si-HPMC) hydrogel, a cellulose ether derivative, that has been used in cartilage, bone tissue engineering and&nbsp; was demonstrated to be biocompatible. Si-HPMC hydrogel crosslinking is promoted by pH neutralization, which makes it a good candidate for bioprinting as it is a cytocompatible process and has a printing time window of about 30 minutes during which the gel viscosity increases.&nbsp; Herein, a thick structure with perfusable channels and cell-laden Si-HPMC was bioprinted.The construct was perfused with a dye solution. It was observed that the dye solution occupied all the volume of the hollow microchannels (MOVIE 1 in supplementary), suggesting that there was no obstruction of microchannels and all channels were in fact interconnected.&nbsp;</p>