Aging Process of Polyamidoamine Dendrimers: Effect of pH and Shaking in the Fluorescence Emission and Aggregation-state

DANIELA E. IGARTÚA; DAVID E. YBARRA; DARÍO M. CABEZAS; ALONSO, SILVIA DEL VALLE; ALVIRA, FERNANDO C.

JOURNAL OF APPLIED POLYMER SCIENCE

JOHN WILEY & SONS INC

Lugar: New York; Año: 2021

0021-8995

In the last years, it has been discovered and intenselystudied the non-traditional intrinsic luminescence of polyamidoamine (PAMAM)dendrimers. Nevertheless, their aging process in aqueous suspension is scarcelystudied, being unknown the causes of the changes in their luminescenceproperties. Hence, this work aims to characterize the amine-terminated (DG4.0)and carboxylic acid-terminated (DG4.5) PAMAM dendrimers of generations 4.0 and4.5, respectively, through the aging process at three different pH conditions,stored with or without shaking. The UV-Vis absorption, the fluorescenceemission, and the dendrimer-size distribution are studied for up to 16 days. Ina different way than the already published works, this work demonstrates thatthere is no chemical change in dendrimers through the aging process, eventhough changes in fluorescence emission are observed. Besides, the changes inthe agglomeration patterns of dendrimers are not related to the change in thefluorescence emission through aging. Moreover, large aggregates of DG4.5 arepresent in water and need to be disrupted by shaking before an in vivo administration.