Patterned and switchable surfaces for biomaterial applications

Chapter 4 – Formation of a chemically patterned substrate for cell microarray applicationsThis result effectively demonstrates the successful formation and alignment of aDNA microarray on top of a prepared surface pattern that is able to influenceadhered cells in two ways. Firstly, the presence of the synthetic polymer patterndirects cell attachment and, secondly, the spotted DNA vectors alter the geneexpression profile of the cell, imparting a significant improvement to current cellmicroarray technology.4.4. ConclusionThis chapter demonstrates the ability of the BioOdyssey Calligraphermicroarrayer to successfully form a polymer microarray that can subsequently beused for cell attachment studies. Tuning the printing parameters, such as humidityand temperature, enables the altering of the printed spots to an idealised state.Additionally, this chapter demonstrates the formation of stable, covalently linkedpolymer microarrays using a robotic spotting device. Utilising a highly reactivecrosslinker to activate soluble synthetic polymers enables the covalent linkage of theresultant arrays to a broad range of organic substrate materials, including low foulingPEG coatings. In the present chapter PEI and PLL were covalently linked to surfaces,however, by judicious choice of a crosslinker a wide range of polymers can be usedfollowing this approach. In addition, polymer patterns can also be generated bymeans other than robotic printing, for example using micromolding, microfluidics,dip-pen nanolithography and microcontact printing.Furthermore, polymer microarray formation enables the pre-patterning ofmicroarray substrates for the formation of biomolecule microarrays. Seeding of cellsonto such microarrays enables the high-throughput study of cellular responses to alibrary of biomolecules of interest. In the present case a TCM was successfully4-152