Protein coatings can be prepared in order to take advantage of their biological functions such as specific binding properties and the ability to enhance or reduce cellular adhesion. The physicochemical surface properties of the substrate have an impact on the protein adsorption and its activity. The activity of adsorbed proteins plays a central role in methods based on the biochemical immobilization used in numerous bioanalytical applications. Controlling the cell-substrate interactions is important in e.g. the development of medical devices and platforms for the cytotoxicity assays and biofilm studies. Cell studies are conventionally performed on rigid substrates. As a flexible and porous substrate, paper is an interesting alternative to the conventional materials. The surface properties of paper can be modified by various surface treatments and paper is also well suited for printing of functional materials. The aim of this work was to develop a paper-based test platform for biochemical and biological assays by modifying the surface properties of the latex or pigment coated paper substrates. The latex coatings were treated by short-wave IR irradiation and by changing the composition of the binary latex coatings. The surface properties of the coatings and adsorption of proteins were studied. On the IR treated latex, a bimodal height distribution of hydrophobic polystyrene (PS) and hydrophilic carboxylated acrylonitrile butadiene styrene copolymer (ABS) was formed. Adsorption of proteins to the two-component latex surface resulted in a patterned structure. Adsorption of avidin to the ABS phase was found to enable a better specific binding activity to biotin. The cell growth of ARPE-19, HepG2 and Staphylococcus aureus on paper substrates with different surface characteristics was studied and printability of viable cells was tested. The latex coatings were found to support the cell growth. Pre-adsorbed avidin inhibited bacterial adhesion on two-component latex.
|Publication status||Published - 2016|
|MoE publication type||G5 Doctoral dissertation (article)|