RT info:eu-repo/semantics/article T1 Refractive index estimation in biological tissues by quantitative phase imaging A1 Acebes Vindel, Ángel José A1 Cairos, Carlos A1 Oliva-García, Ricardo A1 Siverio, Gabriela A1 Trujillo-Sevilla, Juan Manuel A1 Rodríguez-Ramos, Jos´e Manuel A2 Grupo de investigación: Mecanismos Moleculares en NeurodegeneraciónInstituto de tecnologías Biomédicas (ITB). Grupo propio de la Universidad de La Laguna. IP del grupo: Ángel Acebes. https://portalciencia.ull.es/investigadores/81920/detalle K1 Microscopy K1 Quantitative phase imaging (QPI) K1 Refractive index K1 Biological tissues AB The refractive index (RI) of biological tissues represents a relevant optical property that correlates with intrinsicfactors such as dry mass or water content, providing valuable information about tissue composition. First, wereview available methods to measure the RI in biological tissues, making special emphasis on quantitative phaseimaging (QPI) and its ability to obtain RI maps as well as tri-dimensional projections of transparent samples atdiffraction-limited resolution. Second, we propose a simple, general QPI method to estimate the RI of complexmaterials without prior knowledge of sample thickness. Here we have tested several samples in various immersion media with different refractive indices (RIs) to use the lineal relation between the optical path difference(OPD) and the RI of the medium. Least squares regression operates to simultaneously determine the RI and thethickness with diffraction-limited resolution and nanometric transversal sensitivity. Our findings categorize a setof immersion media covering a good RI range, identify possible error sources and uncover the applicability of theQPI method, paving the way to its use on heterogeneous biological tissues SN YR 2023 FD 2023 LK http://riull.ull.es/xmlui/handle/915/35814 UL http://riull.ull.es/xmlui/handle/915/35814 LA en DS Repositorio institucional de la Universidad de La Laguna RD 08-oct-2024