Articolo in rivista, 2021, ENG, 10.1016/j.msec.2020.111593

Development of Spirulina sea-weed raw extract/polyamidoamine hydrogel system as novel platform in photodynamic therapy: Photostability and photoactivity of chlorophyll a

Rizzi, Vito; Gubitosa, Jennifer; Fini, Paola; Fraix, Aurore; Sortino, Salvatore; Agostiano, Angela; Cosma, Pinalysa

Università degli Studi di Bari; Consiglio Nazionale delle Ricerche; Università degli Studi di Catania

The aim of this paper is to present and characterize Polyamidoamine-based hydrogels (PAA) as scaffolds to host photoactive Chlorophyll a (Chl a) from Spirulina (Arthrospira platensis) sea-weed Extract (SE), for potential applications in Photodynamic Therapy (PDT). The pigment extracted from SE was blended inside PAA without further purification, according to Green Chemistry principles. A comprehensive investigation of this hybrid platform, PAA/SE-based, was thus performed in our laboratory and, by means of Visible absorption and emission spectroscopies, the Chl a features, stability and photoactivity were studied. The obtained results evidenced the presence of two main Chl a forms, monomeric and dimeric, interacting with hydrogel polyamidoamines network. To better understand the nature of this interaction, the spectroscopic investigation of this system was performed both before and after the solidification of the hydrogel, that occurred at least in 24 h. Then, focusing the attention on solid scaffold, the Chl a fluorescence lifetime and FTIR-ATR analyses of PAA/SE were carried out, confirming the findings. The swelling and Point Zero Charge (PZC) measurements of solid PAA and PAA/SE were additionally performed to investigate the hydrogel behavior in water. Chl a molecules blended in PAA were (photo) stable and photoactive, and this latter feature was demonstrated showing that the pigment induced, when swelled in water and under irradiation, the formation of singlet oxygen (O), measured by direct and indirect methods.

Materials science & engineering. C, Biomimetic materials, sensors and systems (Print) 119

Keywords

Chlorophyll a, Hydrogels, Photodynamic therapy, Scaffolds, Singlet oxygen, Spirulina extract

CNR authors

Fini Paola

CNR institutes

IPCF – Istituto per i processi chimico-fisici

ID: 446463

Year: 2021

Type: Articolo in rivista

Creation: 2021-02-27 23:22:19.000

Last update: 2021-03-03 16:53:11.000

CNR authors

External IDs

CNR OAI-PMH: oai:it.cnr:prodotti:446463

DOI: 10.1016/j.msec.2020.111593

Scopus: 2-s2.0-85092739880