Microcontact printing of PLL-g-PEG and its derivatives

Abstract

Microcontact printing is a process that has been used for years. The technique works very well with some specific systems such as alkane thiolates on gold and siloxanes on hydroxyl terminated surface. Some less known systems are alkane thiolates on Cu, GaAs, and InP; alkane sulfinates and alkyl phosphines on Au; carboxylic, phosphoric and hydroxamic acids on metal oxides. This work deals with microcontact printing of Poly-L-lysine-g-poly(ethylene glycol) (PLL-g-PEG) and its derivatives. Surfaces with adsorbed PLL-g-PEG are known to be highly protein resistant. The aim of the work is to determine minimal features size that can be stamped, the stability of the molecules on the surface and the homogeneity of the produced patterns. One possible use of this technique is the production of microarrays for use in the biomedical area. If it is possible for microcontact printing to create patterns where one can transfer well defined amounts of a certain substance on geometrically well defined places, it will be quite easy to do hundreds of tests automatically with one single testing plate. This technique is versatile and flexible in pattern size. The pattern size can easily be adapted to the desired conditions. Within this semester thesis, different characterisation methods such as X-ray photoelectron spectroscopy, fluorescence microscopy and atomic force microscopy were used to investigate the stamped patterns.

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Microcontact printing of PLL-g-PEG and its derivatives