Systematic study of Langmuir films of different amino acid derivatives on several subphases

¹ Research Centre for Natural Sciences, Hungarian Academy of Sciences, Institute of Materials and Environmental Chemistry, 1117 Budapest, Magyar tudósok körútja 2., Hungary
² Óbuda University, Faculty of Light Industry and Environmental Engineering, 1034 Budapest, Doberdó u. 6., Hungary

^* Corresponding author: romanszki.lorand@ttk.mta.hu

Abstract

In a Langmuir trough, we studied the formation and the behaviour upon compression of Langmuir films of 1) α-hexadecyl derivative of tert-butoxycarbonylated glycine, respectively α-octadecyl derivative of tert-butoxycarbonylated glycine methyl ester on l- and d-amino acid subphases with/without Cu²⁺ ions, and 2) N-hexadecanoyl derivatives of four l-amino acids (Ala, Ser, Glu, and Phe) on pure water subphase. The films were characterized by their A_c and A₀ molecular areas, Π_c collapse pressure, C⁻¹ compression modulus, and the ${\Pi }_{C_{\max }^{-1}}$ surface pressure at maximum compression modulus. In this contribution, the found peculiarities of the different amphiphile–subphase pairs and the drawn conclusions about the structure of the films and the interactions of the amphiphiles with the subphases are presented.