Dr. M. Eugenia Pérez-Ojeda
Dr. M. Eugenia Pérez-Ojeda
Dr. Maria Eugenia Pérez-Ojeda Rodriguez
H-index 14; total citations 817 (August 2022)
During her PhD project, Dr. Pérez Ojeda successfully achieved the synthesis and study of new hybrid organic-inorganic nanomaterials sensitized through the incorporation of specific fluorescent dyes from the BODIPY family. They showed highly efficient and stable fluorescence and laser emissions distributed throughout the entire visible spectrum, both in solution and in the solid state (within a polymer matrix). Furthermore, to increase the stability of these systems and to avoid thermal degradation of the dyes, which limit their applications, she synthesized new hybrid materials by covalently attaching the dyes to a cubic octasilsesquioxane (POSS) core. The POSS core provides a channel for heat dissipation without affecting the optical properties of the dye. During this period she also pursued a 4-month stay in the Materials Science and Engineering Department of the University of Michigan (Ann Arbor, USA), a world-leading expert in POSS chemistry and technology, in order to prepare fluorescent POSS clusters and porous materials based on these systems.
In addition, she developed new hybrid materials based on POSS for their use in the multivalent display of biomolecules and as nanobuilding blocks for self-assembly by controlling the substitution pattern. Following this approach, she has functionalized POSS with appropriate bioepitopes yielding new glycoconjugated dendrimers with various carbohydrates (mannose, galactose, and lactose). These compounds were tested as multivalent systems for lectin-type proteins that recognise carbohydrates specifically and that are of paramount importance in many biological processes involved in cell recognition. The recognition properties were studied using a series of complementary biophysical techniques, which included surface plasmon resonance, isothermal titration calorimetry (in collaboration with the Institute of Human Virology, University of Maryland (Baltimore, USA). The binding studies, with human galectins and with model lectin ConA, were performed during her 2-month stay in Lund University, (Sweden) using fluorescence anisotropy measurements. Some of her fluorescent glyco-clusters were also studied as specific biomarkers in confocal scanning live cell microscopy in collaboration with the Institute of Oncology of the Central Hospital of Asturias (Oviedo, Spain) and the Microscopy unit from National Centre for Cardiovascular Research (CNIC, Madrid, Spain).
Finally, a study of the aggregation behaviour of glyco-POSS in an aqueous medium was carried out using a combination of biophysical techniques, including fluorescence anisotropy, TEM, GPC, NMR, AFM, DLS and analytical ultra-centrifugation. From this study, it was found that the aggregation process is driven by the hydrophobicity of the octasilsesquioxane core and that the aggregation can be modulated by controlling the overall composition of the organic-inorganic hybrid. The self-assembly of water-soluble POSS in aqueous conditions may be useful for the encapsulation of hydrophobic molecules and for controlled drug delivery.
During her first postdoctoral period (ICTP-CSIC, Madrid, Spain) she kept working on material science through the synthesis of polymeric biomaterials. She developed novel smart polymers which are able to respond to external stimulus. Concretely, she worked in the synthesis of thermosensitive and degradable hydrogels for cell culture and tissue engineering that have been patented.
She joined FAU Erlangen-Nuremberg University (Germany) in May 2016, a year later she was awarded with a Marie Curie postdoctoral fellowship devoted to the development of new hybrid materials based on different carbon allotropes (specially fullerenes, carbon nanoonions and graphene) with the aim of improving their solubility (in order to facilitate their processability and blending) as well as studying their behaviour and tuning their optoelectronic properties. In 2019, she was granted with the emerging talent initiative ETI from Bavaria to initiate her independent career with the support of Prof. Dr. A. Hirsch and, since 2020, she is PI from the DFG collaborative research center SFB-953-A9. Her research spans carbon cages as nanoarchitectures possessing hollow interiors which are of great interest in fundamental supramolecular chemistry and might also find applications such as catalyst, selective recognition, sensoring, drug delivery systems and energy storage and/or conversion. She focuses also on the reductive functionalization of carbon nano-onions (CNOs) or multilayered fullerene shells with a matryoshka-like structure and the fundaments of the alkali metal intercalation process. She explores some applications of CNOs as catalyst for ORR oxygen reduction reaction and as scaffold for magnetic ligands. Furthermore, Dr. Pérez-Ojeda targets the synthesis of carbon-rich void hosts based on functional dyes as perylenebisimides (PBIs) and tetraaryl tetrabenzoporphyrins (TBPs) for supramolecular interactions (endohedral guest binding and chiral self sorting). Among her interests are also the synthesis and study of new fluorescent dyes and oligomeric structures (both covalent and supramolecular) for molecular up- and down-conversion with the aim of boosting power conversion efficiencies in solar cells.