The Submerged Printing of Cells onto a Modified Surface Using a Continuous Flow Microspotter

Abstract

SHORT ABSTRACT This 3D microfluidic printing technology prints arrays of cells onto submerged surfaces. Here we describe how array of cells are delivered microfluidically in 3D flow cells onto submerged surfaces. By printing onto submerged surfaces, cell microarrays were produced that allow for drug screening and cytotoxicity assessment in a multitude of areas including cancer, diabetes, inflammation, infections, and cardiovascular disease. LONG ABSTRACT The printing of cells for microarray applications possesses significant challenges including the problem of maintaining physiologically relevant cell phenotype after printing, poor organization/distribution of desired cells, and the inability to deliver drugs and/or nutrients to targeted areas in the array. Our 3D microfluidic printing technology is uniquely capable of sealing and printing arrays of cells onto submerged surfaces in an automated and multiplexed manner. The design of the microfluidic cell array (MFCA) 3D fluidics enables the printhead tip to be lowered into a liquid-filled well or dish and compressed against a surface to form a seal. The soft silicone tip of the printhead behaves like a gasket and is able to form a reversible seal by applying pressure or backing away. Other cells printing technologies such as pin or ink-jet printers are unable to print in submerged applications. Submerged surface printing is essential to maintain phentotypes of cells and to monitor these cells on a surface without disturbing the material surface characteristics. By printing onto submerged surfaces, cell microarrays are produced that allow for drug screening and cytotoxicity assessment in a multitude of areas including cancer, diabetes, inflammation, infections, and cardiovascular disease.

Maximizing fibroblast adhesion on protein-coated surfaces using microfluidic cell printing

“…A thorough discussion of the advantages of using vertical printing in a submerged environment has been previously reported 18 . Briefly, the CFM allows for the sealing and printing of cellular microarrays onto submerged surfaces in an automated and multiplexed manner.…”

“…Conversely, a vertical, submerged print allows cells to maintain desired phenotypes without disturbing the material surface characteristics. Applications of vertical, submerged-printed, cell microarrays include “drug screening and cytotoxicity assessment in a multitude of areas including cancer, diabetes, inflammation, infections, and cardiovascular disease” 18 .…”

“…A thorough discussion of the advantages of using vertical printing in a submerged environment has been previously reported. 18 Briey, the CFM allows for the sealing and printing of cellular microarrays onto submerged surfaces in an automated and multiplexed manner. The CFM creates a microuidic ow cell array (MFCA) when the vertical printhead tip is lowered into a liquid-lled well and subsequently forms a watertight seal on the bottom of the well.…”

“…Applications of vertical, submerged-printed, cell microarrays include "drug screening and cytotoxicity assessment in a multitude of areas including cancer, diabetes, inammation, infections, and cardiovascular disease". 18 In this work, the versatility of the CFM is used to not only alter the surface, but also the ow rates, tubing size, print head dimensions, and surface contact time (pause time). These parameters are grouped into either mechanical parameters (i.e., tubing size, print head dimensions, print pauses) or biological parameters (i.e., ow rate and surface biology).…”