Nanobiotechnology for health-care

Uptake of Chlorin e6 derivatives by temperature sensitive polymer Dextran-graft-PNIPAM

Yu. Kuziv1, V. Zorin2,3, I. Kravchenko3, T. Zorina3, N. Kutsevol1 

1Taras Shevchenko National University of Kyiv, 60 Volodymyrs'ka str., 01601 Kyiv, Ukraine
2Belarussian State University, pr. Nezavisimosti 4, Minsk, 220030 Belarus 3International State Ecological Unversity named after A.D.Sakharov BSU, Dolgobrodskaya Street, 23/1, Minsk, 220070,  Belarus
E-mail: kutsevol@ukr.net
	Temperature responsible polymer poly(N-isopropylacrylamide) is discussed last years as promising drug delivery system.  We have studied the possibility of encapsulation of Chlorin e6 derivatives into stimuli responsive polymer Dextran-graft-poly(N-isopropylacrylamide). Chlorin e6 derivatives are соnsidered as potential photosensitizers for photodynamic anticancer therapy. We tested nanocomposites polymer/Chlorin e6 (Ce6), polymer/dimethylether of Chlorin e6 (DME Ce6) and polymer/trimethylester of Chlorin e6 (TME Ce6) by Quasi Elastic Light Scattering, FTIR, Spectral and Fluorescence polarization measurements.Ce6 derivatives are not soluble in water and forms aggregates in aqueous solutions. The encapsulation of this dyes into water-soluble polymer can prevent an aggregation process. The photophysical properties of the copolymer/photosensitizers nanocomposites as function of temperature in the region of the conformational transition of polymer matrix have been studied. It was shown that at low temperatures all photosensitizers interacted weakly with polymer phase. As a result, absorption and fluorescence properties of Ce6 derivatives in aqueous and polymer solutions are practically identical. Heating above Low Critical Solution Temperature has a significant influence on the fluorescent characteristics of non-polar Chlorins indicating the binding of DME Ce6 and TME Ce6 molecules in the polymer matrix. The results of our research with several structurally similar chlorin-type photosensitizers clearly show that the applicability of Dextran-graft-poly(N-isopropylacrylamide) as smart drug-delivery system is dependent strongly on the properties of loaded dye.
Acknowledgment
This publication is supported in part by the Ministry of the Education and Science of Ukraine: joint Ukrainian-Belarusian research and development projects “Design and physico-chemical properties of novel multicomponent nanosystems for the treatment and diagnostics of solid tumors” M/110 (2019-2020), and with the financial support of the Belarusian Republican Foundation for basic research, grant no. M19UKRG-002.