**About the Editors**

## **Cristina Palet**

Dr. Cristina Palet has been linked to the Universitat Autonoma de Barcelona since 1989, ` obtaining her Chemistry degree, and in 1994, achieved her doctor's degree with Cum Laude with the Prof's tutorship Manuel Valiente and Prof. Maria Munoz. Since March 2000, she has been a ˜ Professor of Titular (Analytical Chemistry) at the Chemistry Department of Universitat Autonoma de ` Barcelona. Her research work focuses on:

In Basic research, Separation Systems have been developed, primarily by using membrane setups in flat and hollow fiber configurations (liquid, polymeric and composite membranes) and chromatographic materials (resins).

Furthermore, she studies the characterization and use of bio-waste materials for separation purposes, so different biomasses have been also studied, mainly for metals (human hair, dog hair, degreased wool and chicken feathers as keratin biomaterials from animal origin, and cork and algae as vegetal origin have been used). Nanoparticles (NPs) are prepared and characterized, mainly for their immobilization in different supports to improve the efficiency and/or the selectivity of heavy metal adsorption. One application of NPs (SPION) for the adsorption of PAHs has been also checked.

In a more applied field, the extraction, identification and quantification of PAHs by Gas Chromatography with a Mass Detector have been developed. In the last few years, the development of new sensor materials is one research line of her interest, mainly applied to environmental and biomedical applications. To follow many of such separation and detection systems, different Instrumental Techniques have been used and some analytical procedures have been developed Some Design of Experiments Systems have been applied to optimize different designed separation methodologies. Beamline time obtained this in 2018, in ALBA (Catalunya, Spain) and Diamond (England) Synchrotrons to determine the speciation of chromium onto different biomass systems, for the first time.

#### **Julio Bastos-Arrieta**

Dr. Julio Bastos Arrieta o got his Master's degree (September 2010) and Ph.D. in Chemistry with "Cum Laude"/International Doctor Quality honors (October 2014). In June 2015, he was hired as Postdoc Researcher for the Separation Techniques and Waste Management Group (SETRI), currently known as Resource Recovery and Environmental Management (R2EM) at Universitat Politecnica de ` Catalunya (UPC) under the supervision of Drs. Joan de Pablo and Ignasi Casas. There he co-directed the Master's theses of students and took part in different research projects with public and private entities, for example: Empresa Nacional de Residuos Radiactivos (ENRESA, Spain), Institute for Transuranium Elements (ITU; Germany), Universitat de Girona (UdG, Spain) and Universitat de Barcelona (UB, Spain).

In September 2017, he moved to Dresden (Germany) to enroll as a Postdoc in the Group of Prof. Eychmuller, at Technische Universit ¨ at Dresden (TUD), to work on the preparation and analysis ¨ of nanoactive colloids. He came back to Spain in 2020 and carried out a research stay at UAB (June-September 2020) based on the impedimetric analysis of nanomaterials. In September 2020, he joined the Molecular and Industrial Biotechnology group (GBMI) at the UPC as Senior Postdoc, under the supervision of Dr. Tzanko Tzanov. From February to July 2021, he taught a class in UAB as a visiting Professor for the Analytical Chemistry Department.

Since November 2021 he enrolled in the Universitat de Barcelona as a Tenure Lecturer Professor and researcher of the Electroanalysis Group, of the Analytical Chemistry Department. He collaborates actively with his former colleagues in TUD, UPC and UAB. His main research interests include the preparation and characterization of nanomaterials (e.g., nanoparticles, active colloids) and their application towards the electrocatalytical enhancement of sensing systems.
