biostudies-literatureNusterer MNational Institutes of HealthNIGMS NIH HHS108236https://www.ebi.ac.uk/biostudies/studies/S-EPMC8622871biostudies-literatureUnknown177A novel cell culture technology, consisting of hollow alginate tubes, OD ~550 <i>μm</i>, ID ~450<i>μm</i> containing a cell suspension, provides stress-free conditions. Cells reach confluency in approximately ten days with cell densities of 0.5 - 1 billion cells per <i>mL</i>. Tubes are manufactured in a tri-axial needle extruder with three concentric flows. The cell suspension flows in the inner needle (N1), the alginate solution flows in the annulus between N1 and the second needle (N2) and a <i>CaCl</i> ₂ solution is the sheath fluid between the second and third needle (N3). Beyond the tip of N2, the sheath solution is in contact with the alginate and <i>Ca</i> ²⁺ diffuses into the alginate solution and crosslinks it to form an alginate microtube around the core flBiochemical engineering journalTheoretical and Experimental Investigation of Alginate Microtube Extrusion for Cell Culture Applications.PMC8622871R41 GM1347301R41GM134730Rauch JViljoen HNusterer MfalseTheoretical and Experimental Investigation of Alginate Microtube Extrusion for Cell Culture Applications.A novel cell culture technology, consisting of hollow alginate tubes, OD ~550 <i>μm</i>, ID ~450<i>μm</i> containing a cell suspension, provides stress-free conditions. Cells reach confluency in approximately ten days with cell densities of 0.5 - 1 billion cells per <i>mL</i>. Tubes are manufactured in a tri-axial needle extruder with three concentric flows. The cell suspension flows in the inner needle (N1), the alginate solution flows in the annulus between N1 and the second needle (N2) and a <i>CaCl</i> ₂ solution is the sheath fluid between the second and third needle (N3). Beyond the tip of N2, the sheath solution is in contact with the alginate and <i>Ca</i> ²⁺ diffuses into the alginate solution and crosslinks it to form an alginate microtube around the core fl2022-01-01T00:00:00Z2022 Jan2025-04-26T13:20:30.314Z2025-04-06T14:14:42.121ZS-EPMC86228713484051710.1016/j.bej.2021.108236