Patterned and switchable surfaces for biomaterial applications

Chapter 1 - Introductionattached to the coating were formed that could be used for subsequent assay of cellmaterialinteractions. Automated X-ray photoelectron spectroscopy (XPS), contactangle and time of flight secondary ion mass spectroscopy (ToF-SIMS) analysisallows for the rapid characterisation of the formed polymer array and the ability tomatch observed cellular behaviour with particular chemical or structural properties ofindividual polymer spots [146].1.4.4. Cell microarraysA number of different approaches to cell microarrays have been explored enablingthe investigation of gene expression, cell surface interactions particularly withantibodies, ECM composition, cell migration and proliferation, the effects of drugson cellular activity and a number of other areas [45]. A review of cell microarrays ingeneral has been recently published [45]. Of great interest has been the developmentof TCMs [8]. A schematic representation of the TCM formation is shown in Figure1.8. TCM formation consists of four key steps. Firstly, a nucleic acid microarray isformed using typical DNA microarray formation techniques, which have previouslybeen reviewed in detail [15, 16, 82, 96]. Secondly, cells are seeded and attach ontothe surface. Thirdly, DNA detaches from the surface and is taken up by the cells andfinally overexpressed within the cells or, when using RNA interference (RNAi), thetarget gene is silenced. Various genomic studies have been undertaken utilisingTCMs, such as the determination of the cellular position of expressed proteins,detection of gene products involved with apoptosis and the screening of agonists andantagonists of G-protein coupled receptors (GPCRs) [8, 147, 148]. A list of currentapplications of cell microarrays using transfection is shown in Table 1.1.1-46