FIELD-CYCLING NMR RELAXOMETRY AS A TOOL FOR THE CHARACTERIZATION OF THE ELASTIC PROPERTIES OF LIPOSOMES

E. ANOARDO; M. B. MARZOLA; C. FRAENZA

Conferencia; 11th Conference on Field Cycling NMR Relaxometry; 2019

It has been clearly established that liposomes with enhanced membrane elasticity favor the penetration of drugs through the skin [1-4]. However, details of the underplaying mechanisms have not been clearlyunderstood so far [2,3,5-7]. The elasticity of liposome membranes has been mainly characterized throughtwo different approaches: vesicle deformability as observed in extrusion experiments [8-10], andmeasurements of the bending elastic constant [11-13]. A discussion about the equivalence of these twoapproaches has been considered [14]. Moreover, the measurement of the bending elastic constant (ormodulus) showed a marked dependence on the used experimental technique [15]. This fact has a closerelationship on how the physics involved in each experimental protocol & technology interacts with thesample system, which in turn strongly depends on how it was manipulated according to the needs andrequirements of the used technique. In this context, field-cycling NMR relaxometry can be considered asa promising alternative [16]. It is hardly invasive, while the information on the elastic properties can beobtained from the nuclear magnetic relaxation of the lipid protons (liposomes suspended in deuteratedwater). In this opportunity we present a general overview of the problem, and some new results thatsupport a deeper analysis about the pros and cons of the FFC-relaxometry technique in confront withother experimental approaches.  References[1] G. Cevc and U. Vierl, J. Control. Release 141, 277-299 (2010).[2] M. L. Vázquez-Conzález, R. Bernard, A. C. Calpena, O. Domènech, M. T. Montero and J. Hernández-Borrell, Int. J. Pharm. 461, 427-436 (2014). [3] M. F. Peralta, M. L. Guzmán, A. P. Pérez, G. A. Fórmica, G. A. Apezteguia, E. L. Romero, M. E. Olivera and D. C. Carrer, Sci. Rep. 8: 13253 (2018).[4] M. Sacha, L. Faucon, E. Hamon, I. Ly, E. Haltner-Ukomadu, Biomed. Pharmacother. 111, 785-790 (2019).[5] M. Ashtikar, K. Nagarsekar and A. Fahr, J. Control. Release 242, 126-140 (2016).[6] H. A. E. Benson, Elastic Liposomes for Topical and Transdermal Drug Delivery, In: D'Souza G. (Eds) Liposomes: Methods in Molecular Biology (vol 1522). Springler/Humana Press, New York, 2017.[7] H. Ibaraki, T. Kanazawa, C. Oogi, Y. Takashima and Y. Seta, J. Drug Deliv. Sci. Technol. 50, 155-162 (2019).[8] G. Cevc, A. Shätzlein and H. Richardsen, Biochim Biophys. Acta 1564, 21-30 (2002).[9] S. Ternullo, P. Basnet, A. M. Holsæter, G. E. Flaten, L. Weerd and N. Skalko-Basnet, Eur. J. Pharm. Sci. 125, 163-171 (2018).[10] G. S. El-Feky, M. M. El-Naa and A. A. Mahmoud, J. Drug Deliv. Sci. Technol. 49, 24-34 (2019).[11] R. Dimova, Adv. Colloid Interfac. Sci. 208, 225-234 (2014).[12] O. Et-Thafaky, N. Delorme, C. Gaillard, C. Mériadec, F. Artzner, C. Lopez and F. Guyomarc?h, Lagmuir 33, 5117-5126 (2017).[13] M. F. Peralta, H. Smith, D. Moody, S. Tristam-Nagle and D. C. Carrer, J. Phys. Chem. B 122, 7332-7339 (2018).