Tetramer of aniline as a structural analog of polyaniline – Promising material for biomedical application

Abstract

Polyaniline (PANI) is a polyconjugated polymer that attracts the attention of scientists for many years because of the possibility of its use in both organic electronics and as material for biomedical and electrophysical application, thanks to its high conductivity, chemical stability, the ability of redox and non-oxidative doping, biocompatibility and selective affinity for different types of biopolymers. However, volatility of physical and chemical properties of PANI limits its wide practical application as a component of composites. Those drawbacks could be overcome by the use of aniline oligomers that demonstrate reliable control and adjustment of their structure, better solubility and processability. In this research, we examined physical and chemical properties of phenyl end-capped tetraaniline (TANI) and its films, which are the lowest molecular weight derivatives of aniline in comparison with PANI. Self-organized thin film structures of TANI with well-defined morphology were prepared via transfer of Langmuir films obtained on the water-air interface. The behavior of TANI as bioseparating material as studied with spectral correlation technique on the examples of separation of nucleic acids and proteins was shown to be similar to PANI’s behavior. In particular, TANI demonstrates sorption inertness towards double strained nucleic acids and binds the proteins depending on their isoelectric points and hydrophobicity (“negative selection”).