1. Live Cell Printing

■ Research Purpose

  • To optimize stable and precise cell printing with desired printing performance.

■ Research Contents

  • Cell-laden jet morphology
       Since cells included in jet could affect performances, such as droplet number, droplet velocity, and flight angle, it is important to understand cell effect on jetting morphology in order to control printing performances. Using high-speed imaging technique, cell-laden jet morphology under diverse parametric conditions can be analyzed.                                                                                                                                                                    

  • Precise cell printing
       In order to precisely deposit cell in predeterminate position, cell printing through nozzle having 30-µm diameter, which is compared to that of mammalian cell, is essential. This cell printing can lead to easy control of cell number in droplet by geometric effect. Cell viability and proliferation are also confirmed through 30-µm sized nozzle.

(Live cell printing process with ink-jet printer)

(Printed live cell)

2. 2D Cell Patterning & Artificial Skin

■ Research Purpose

  • To mimic microenvironment of our body for development in both fundamental biology & tissue engineering.

■ Research Contents

  • Spatio-temporal placement of living cells and surrounding ECM is highly important due to its connection with cellular behaviors and functions. As inkjet printing system allows fine deposition of cells and biomaterials in predetermined designs, mimicking microenvironment is possible by printing heterotypic cells, appropriate biomaterials, and multiple biochemical cue molecules. Cell micropatterns from 2D to 3D constructs are being printed for various applications such as biological assays, co-culture models, and artificial skin substitutes. 

  • Cell micropatterning using inkjet printing

(Cell micropatterns fabricated by inkjet printing)

   Cells in our body are aligned and localized in certain patterns. Mimicking the arranged microenvironment is the key factor in tissue engineering field because this cellular architecture is closely related with its function. With special inkjet direct cell printing technology of our lab, fine cell micropatterns are fabricated by using piezoelectric inkjet printers. Without using complicated fabrication process or supporting materials, cells are inkjet-printed to be aligned in desired patterns. Printed cell patterns are applied to biological assays, heterotypic co-cultures, and artificial tissue fabrication.

  • 3D Skin Printing

(Printed skin tissue with wrinkle structure)

   Demand for artificial skin substitutes has been a big issue in skin injury treatment and also in cosmetology field. With inkjet printing, 3D skin-like constructs with multiple thin layers are fabricated. High resolution inkjet printing system enables fine deposition of skin cells and surrounding biomaterials. From simple layered skin constructs to functionally designed skin constructs can be fabricated. Both wound applicable and drug/cosmetic testable skin models are together being studied.

(Printed test model for whitening effect)

3. 3D Hydrogel Structure Fabrication

■ Research Purpose

  • To fabricate an artificial tissue 3D structure using bioprinting technology

■ Research Contents

  • The inkjet printing technology involves the generation, control and deposition of very small drops of liquid with a volume of ~2 picolitres or a drop diameter of ~17 µm. A piezoelectric drop-on-demand (DOD) inkjet printer, one of the most common printing techniques, has a piezo crystal that receives electric pulses and produces pressure waves inside a nozzle channel to disperse the ink into picolitre droplets. The DOD printer can deposit tens of thousands of drops per second and produce patterns with high positional accuracy, high speed and low cost. Owing to its unique features such as picolitre drop generation on demand, wide range of nozzle diameter, and high printing speed with deposition of over 10,000 drops per second on predefined locations, inkjet bioprinting offers great advantages to fabricate biological 3D constructs composed of living cells, biological materials and biochemicals with high spatial resolution

(3D Inkjet printing system)

(Printed hydrogel constructs)