When Cellulose Moves: Smart Sensors and Actuators Francisco Sousa, José F. Malta, Ana P. C. Almeida Advanced Materials Technologies, 2025 Cellulose, the most abundant biopolymer on Earth, has rapidly gained attention as a key component in the development of smart materials capable of dynamic and adaptive behavior. This review highlights the unique motion and actuation capabilities of cellulose‐based systems, focusing on their ability to convert external stimuli into mechanical movement. The recent progress in cellulose‐derived soft actuators that respond to moisture, electric fields, thermal and light input, and magnetic forces is detailed – enabling programmable shape changes, bending, twisting, and locomotion. Alongside these, cellulose‐based soft sensors that transduce environmental cues though magnetic, resistive and capacitive mechanisms are examined. Special emphasis is placed on the synergy between sensing and actuation in multifunctional devices that mimic natural movement and responsiveness. Applications in wearable devices, soft robotics, biomedical systems, energy harvesting, smart packaging, and bioinspired technologies are explored to demonstrate the practical potential of these materials. The challenges in achieving robust, reversible, and multi‐stimuli‐responsive motion are also addressed, and future directions for scaling up and integrating cellulose‐based smart systems into real‐world applications are proposed.
The Clear Choice: Developing Transparent Cork for Next-Generation Sustainable Materials Pedro Gil, Pedro L. Almeida, Maria H. Godinho, Ana P. C. Almeida Macromol, 2025 Many modern technologies rely on materials that harm the environment. Glass manufacturing, for instance, is both expensive and environmentally damaging. In response, scientists have developed a technique to replace glass with transparent wood, an innovative, versatile, and sustainable alternative. Wood naturally retains heat, is durable, and remains cost-effective, making it promising substitute for glass and plastic in window production. This innovation highlights the urgent need for eco-friendly technologies to replace or improve existing materials. This work explores cork as a sustainable alternative for producing transparent materials, potentially replacing transparent wood. Unlike wood, cork can be harvested from the same tree for up to 300 years. The process followed a method like transparent wood production, involving delignification, bleaching, and forced polymer impregnation. The choice of bleaching agent significantly impacted results—samples treated with sodium hypochlorite solution appeared whiter but became extremely fragile, whereas hydrogen peroxide preserved mechanical properties better. The resin-to-hardener ratio was crucial, with higher resin content improving polymer infiltration and transparency. While fully transparent cork was not achieved, the resulting translucent material lays the groundwork for future research in this field.
Transparent Paper Ana Almeida Handbook of Paper Based Sensors and Devices Volume 1 Materials and Technologies, 2025
Nature-Inspired Cellulose-Based Active Materials: From 2D to 4D Marta I. Magalhães, Ana P. C. Almeida Applied Biosciences, 2023 Multifunctional materials and devices with captivating properties can be assembled from cellulose and cellulose-based composite materials combining functionality with structural performance. Cellulose is one of the most abundant renewable materials with captivating properties, such as mechanical robustness, biocompatibility, and biodegradability. Cellulose is a low-cost and abundant biodegradable resource, CO2 neutral, with a wide variety of fibers available all over the world. Over thousands of years, nature has perfected cellulose-based materials according to their needs, such as function vs. structure. Mimicking molecular structures at the nano-, micro-, and macroscales existing in nature is a great strategy to produce synthetic cellulose-based active materials. A concise background of cellulose and its structural organization, as well as the nomenclature of cellulose nanomaterials, are first addressed. Key examples of nature-designed materials with unique characteristics, such as “eternal” coloration and water-induced movement are presented. The production of biomimetic fiber and 2D fiber-based cellulosic materials that have attracted significant attention within the scientific community are represented. Nature-inspired materials with a focus on functionality and response to an external stimulus are reported. Some examples of 3D-printed cellulosic materials bioinspired, reported recently in the literature, are addressed. Finally, printed cellulosic materials that morph from a 1D strand or 2D surface into a 3D shape, in response to an external stimulus, are reported. The purpose of this review is to discuss the most recent developments in the field of “nature-inspired” cellulose-based active materials regarding design, manufacturing, and inspirational sources that feature existing tendencies.
Cholesteric-type cellulosic structures: from plants to applications Ana P. C. Almeida, João P. Canejo, Pedro L. Almeida, Maria Helena Godinho Liquid Crystals, 2019 The structural support of plant cells is provided by the cell wall, which major load-bearing component is an array of hierarchical orientedhierarchical-oriented cellulose nano-, micro- and meso-structures of cellulose microfibrils. Cellulosic structures can respond to humidity changes by expanding or shrinking and this allows, for example, the dispersion of seeds. Previous studies have shown that nanorods, extracted from cell walls, can generate lyotropic liquid crystals that are at the origin of solid cholesteric-like arrangements. Not only photonic films, but also right and left helical filaments, anisotropic films with the ability to bend back and forth under the action of a moisture gradient at room temperature, are some of the materials that were produced from cellulose liquid crystal systems. This work is a review that focus on liquid crystalline-based structures obtained from cellulosic materials and how small perturbations on their structures affect significantly the response to external stimulus and interactions with the environment. Special emphasis is given to cholesteric-like organization of cellulose structures existing in plants, which are an inspiration for the production of the next generation of soft interactive materials. Graphical Abstract
Spotting plants’ microfilament morphologies and nanostructures Ana P. Almeida, João Canejo, Urban Mur, Simon Čopar, Pedro L. Almeida, et al. Proceedings of the National Academy of Sciences of the United States of America, 2019 Significance Microfibers existing in the tracheary systems of plants are crucial for the plants to survive. These microfilaments are curled up, forming left-handed helices that make the contour of tubes responsible for the transport of water and nutrients from the roots to the leaves. The microfilaments present mechanical properties that vary from plant to plant despite having similar polygonal-helical shapes and cellulose skeletons. Here we show that the surface morphology of the microfilaments, sensed by nematic liquid crystal droplets, is at the origin of entanglements, which are responsible for the mechanical behavior of microfilaments. This work introduces routes for the accurate characterization of plants’ microfilaments and to produce bioinspired textiles.
Mechanochromic cholesteric liquid crystal devices for mechanical strain detection F Sousa, J Santos, JF Malta, JP Canejo, APC Almeida, PL Almeida Scientific Reports , 2026 2026
When Cellulose Moves: Smart Sensors and Actuators F Sousa, JF Malta, APC Almeida Advanced Materials Technologies 10 (23), e01426 , 2025 2025 Citations: 4
Transparent Paper A Almeida The Handbook of Paper-Based Sensors and Devices: Volume 1: Materials and … , 2025 2025 Citations: 1
The Clear Choice: Developing Transparent Cork for Next-Generation Sustainable Materials P Gil, PL Almeida, MH Godinho, APC Almeida Macromol 5 (2), 17 , 2025 2025
Design Photonics Materials and Devices Inspired by Nature A Almeida, ML Garcia, M Godinho, V Katanaev, N Pop, M Dabbicco, ... Nanoscale Imaging, Sensing, and Actuation for Biomedical Applications XXII … , 2025 2025
Nature inspired cellulose-based networks for moisture sensors M Silva, J Santos, F Sousa, J Malta, PL Almeida, MH Godinho, ... Nanoscale Imaging, Sensing, and Actuation for Biomedical Applications XXII … , 2025 2025
Introduction about understanding interaction light-biological surfaces: possibility for new electronic materials and devices (PhoBioS) D Fixler, V Katanaev, ML Garcia, M Godinho, N Pop, J Radovanovic, ... Biomedical Spectroscopy, Microscopy, and Imaging III, PC130061R , 2024 2024
How nature can help to design and elaborate new photonics materials and devices V Katanaev, D Fixler, ML Garcia, M Godinho, N Pop, J Radovanovic, ... Biomedical Spectroscopy, Microscopy, and Imaging III, PC130060X , 2024 2024 Citations: 1
Exploring the potential of cellulose liquid crystal devices: Insights from nature’s design S Almeida, A Almeida, P Almeida, MH Godinho Proceedings of the SPIE PC13016, Liquid Crystals Optics and Photonic Devices … , 2024 2024 Citations: 1
Nature-inspired cellulose-based active materials: From 2D to 4D MI Magalhães, APC Almeida Applied Biosciences 2 (1), 94-114 , 2023 2023 Citations: 27
Crosslinked bacterial cellulose hydrogels for biomedical applications APC Almeida, JN Saraiva, G Cavaco, RP Portela, CR Leal, RG Sobral, ... European Polymer Journal 177, 111438 , 2022 2022 Citations: 77
Cellulose Filaments for Responsive and Functional Materials APC Almeida PQDT-Global , 2021 2021 Citations: 1
Spotting plants’ microfilament morphologies and nanostructures AP Almeida, J Canejo, U Mur, S Čopar, PL Almeida, S Žumer, ... Proceedings of the National Academy of Sciences 116 (27), 13188-13193 , 2019 2019 Citations: 9
Helices from cellulose-based materials MH Godinho, A Almeida, L Querciagrossa, P Silva, J Canejo, P Almeida, ... ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 257 , 2019 2019
Reversible water driven chirality inversion in cellulose-based helices isolated from Erodium awns APC Almeida, L Querciagrossa, PES Silva, F Goncalves, JP Canejo, ... Soft Matter 15 (13), 2838-2847 , 2019 2019 Citations: 31
Cellulose‐based biomimetics and their applications APC Almeida, JP Canejo, SN Fernandes, C Echeverria, PL Almeida, ... Advanced Materials 30 (19), 1703655 , 2018 2018 Citations: 271
Elastomeric patterns probed by a nematic liquid crystal AC Trindade, APC Almeida, JP Canejo, P Patrício, P Pieranski, ... Molecular Crystals and Liquid Crystals 657 (1), 136-146 , 2017 2017 Citations: 3
Tuning surface wrinkles of Janus spheres in supercritical carbon dioxide AC Trindade, R Craveiro, APC Almeida, JP Canejo, A Paiva, S Barreiros, ... The Journal of Supercritical Fluids 120, 125-131 , 2017 2017 Citations: 12
MOST CITED SCHOLAR PUBLICATIONS
Cellulose‐based biomimetics and their applications APC Almeida, JP Canejo, SN Fernandes, C Echeverria, PL Almeida, ... Advanced Materials 30 (19), 1703655 , 2018 2018 Citations: 271
Microencapsulation of oregano essential oil in starch-based materials using supercritical fluid technology AP Almeida, S Rodríguez-Rojo, AT Serra, H Vila-Real, AL Simplicio, ... Innovative food science & emerging technologies 20, 140-145 , 2013 2013 Citations: 147
Crosslinked bacterial cellulose hydrogels for biomedical applications APC Almeida, JN Saraiva, G Cavaco, RP Portela, CR Leal, RG Sobral, ... European Polymer Journal 177, 111438 , 2022 2022 Citations: 77
Processing cherries (Prunus avium) using supercritical fluid technology. Part 2. Evaluation of SCF extracts as promising natural chemotherapeutical agents AT Serra, AA Matias, APC Almeida, MR Bronze, PM Alves, HC De Sousa, ... The Journal of Supercritical Fluids 55 (3), 1007-1013 , 2011 2011 Citations: 58
Reversible water driven chirality inversion in cellulose-based helices isolated from Erodium awns APC Almeida, L Querciagrossa, PES Silva, F Goncalves, JP Canejo, ... Soft Matter 15 (13), 2838-2847 , 2019 2019 Citations: 31
Nature-inspired cellulose-based active materials: From 2D to 4D MI Magalhães, APC Almeida Applied Biosciences 2 (1), 94-114 , 2023 2023 Citations: 27
Processing triacetyl-β-cyclodextrin in the liquid phase using supercritical CO2 AVM Nunes, APC Almeida, SR Marques, ARS de Sousa, T Casimiro, ... The Journal of Supercritical Fluids 54 (3), 357-361 , 2010 2010 Citations: 21
Down conversion photoluminescence on PVP/Ag-nanoparticles electrospun composite fibers AC Baptista, AM Botas, APC Almeida, AT Nicolau, BP Falcão, MJ Soares, ... Optical Materials 39, 278-281 , 2015 2015 Citations: 14
Tuning surface wrinkles of Janus spheres in supercritical carbon dioxide AC Trindade, R Craveiro, APC Almeida, JP Canejo, A Paiva, S Barreiros, ... The Journal of Supercritical Fluids 120, 125-131 , 2017 2017 Citations: 12
Hybrid polysaccharide-based systems for biomedical applications PIP Soares, C Echeverria, AC Baptista, CFC João, SN Fernandes, ... Hybrid polymer composite materials, 107-149 , 2017 2017 Citations: 12
Spotting plants’ microfilament morphologies and nanostructures AP Almeida, J Canejo, U Mur, S Čopar, PL Almeida, S Žumer, ... Proceedings of the National Academy of Sciences 116 (27), 13188-13193 , 2019 2019 Citations: 9
Supercritical fluids strategies to produce hybrid structures for drug delivery AV Nunes, S Rodriguez-Rojo, AP Almeida, AA Matias, D Rego, ... Journal of Controlled Release 148 (1), e11-e12 , 2010 2010 Citations: 6
When Cellulose Moves: Smart Sensors and Actuators F Sousa, JF Malta, APC Almeida Advanced Materials Technologies 10 (23), e01426 , 2025 2025 Citations: 4
Elastomeric patterns probed by a nematic liquid crystal AC Trindade, APC Almeida, JP Canejo, P Patrício, P Pieranski, ... Molecular Crystals and Liquid Crystals 657 (1), 136-146 , 2017 2017 Citations: 3
Utilização da tecnologia supercrítica no isolamento de ingredientes biofuncionais–Aplicação ao caroço de azeitona e refugo de cereja APC Almeida PQDT-Global , 2009 2009 Citations: 2
Transparent Paper A Almeida The Handbook of Paper-Based Sensors and Devices: Volume 1: Materials and … , 2025 2025 Citations: 1
How nature can help to design and elaborate new photonics materials and devices V Katanaev, D Fixler, ML Garcia, M Godinho, N Pop, J Radovanovic, ... Biomedical Spectroscopy, Microscopy, and Imaging III, PC130060X , 2024 2024 Citations: 1
Exploring the potential of cellulose liquid crystal devices: Insights from nature’s design S Almeida, A Almeida, P Almeida, MH Godinho Proceedings of the SPIE PC13016, Liquid Crystals Optics and Photonic Devices … , 2024 2024 Citations: 1
