Multifunctionalized Polyamides Prepared by Facile Ugi Reaction as Thermosensitive, Biocompatible and Antibacterial Biomaterials

摘要

A series of multifunctionalized polyamides were facilely prepared by Ugi four-component polymerization (Ugi-4CP) in one-pot method at room temperature using several diacids, aldehydes, 1,4 bis-(3-aminopropyl) piperazine and tert-butyl isocyanide as monomers. The simple combination of mono- mers in Ugi-4CP led to formation of nine thermosensitive polyamides in water, and their lower critical solution temper- atures (LCSTs) were in range of 13.1-70.1°C. The LCSTs for the subsequently-quaternized polyamides (PBA-800-Br, PIA-800-Br and PCA-800-Br) were easily readjusted to the desired value in the inorganic salt solutions. PBA-800-Br and PIA-800-Br ex- hibited high antibacterial activity against Gram negative E. coli and Gram positive S. aureus. Confocal laser scanning micro- scope (CLSM) manifested the clear internalization into the cellular inside for the fluorescent molecule-labelled polyamides. After 24–72 hours of incubation in polyamide solution, the viability rate of HeLa cells reached up to 80–141%, indicating the excellent biocompatibility. In conclusion, the thermosensi- tive, antibacterial and biocompatible polyamides have great potential to be used as biomaterials.