Instytut Podstawowych Problemów Techniki

Ahmed A., Nuria A., Bethany A., Pierini F., Zargarian S., Interfacing with the Brain: How Nanotechnology Can Contribute, ACS Nano, ISSN: 1936-0851, DOI: 10.1021/acsnano.4c10525, pp.A-CJ, 2025

Abstract:
Interfacing artificial devices with the human brain is the central goal of neurotechnology. Yet, our imaginations are often limited by currently available paradigms and technologies. Suggestions for brain–machine interfaces have changed over time, along with the available technology. Mechanical levers and cable winches were used to move parts of the brain during the mechanical age. Sophisticated electronic wiring and remote control have arisen during the electronic age, ultimately leading to plug-and-play computer interfaces. Nonetheless, our brains are so complex that these visions, until recently, largely remained unreachable dreams. The general problem, thus far, is that most of our technology is mechanically and/or electrically engineered, whereas the brain is a living, dynamic entity. As a result, these worlds are difficult to interface with one another. Nanotechnology, which encompasses engineered solid-state objects and integrated circuits, excels at small length scales of single to a few hundred nanometers and, thus, matches the sizes of biomolecules, biomolecular assemblies, and parts of cells. Consequently, we envision nanomaterials and nanotools as opportunities to interface with the brain in alternative ways. Here, we review the existing literature on the use of nanotechnology in brain–machine interfaces and look forward in discussing perspectives and limitations based on the authors’ expertise across a range of complementary disciplines─from neuroscience, engineering, physics, and chemistry to biology and medicine, computer science and mathematics, and social science and jurisprudence. We focus on nanotechnology but also include information from related fields when useful and complementary.

Zakrzewska A., Kosik-Kozioł A., Zargarian S., Zanoni M., Gualandi C., Lanzi M., Pierini F., Lemon Juice-Infused PVA Nanofibers for the Development of Sustainable Antioxidant and Antibacterial Electrospun Hydrogel Biomaterials, BIOMACROMOLECULES, ISSN: 1525-7797, DOI: 10.1021/acs.biomac.4c01466, Vol.26, No.1, pp.654-669, 2025

Abstract:
Cross-linking bonds adjacent polymer chains into a three-dimensional network. Cross-linked poly(vinyl alcohol) (PVA) turns into a hydrogel, insoluble structure exhibiting outstanding sorption properties. As an electrospinnable polymer, PVA enables the creation of nanofibrous hydrogels resembling biological tissues, thus ideal for nature-inspired platforms. PVA properties are easily adjustable through additives and an appropriate cross-linking method. Drawing inspiration from environmentally safe approaches, this work developed a new “green” method of low-temperature PVA cross-linking. Nanofibers were electrospun from a precursor solution of PVA dissolved in fresh lemon juice, stabilized by heating at 60 °C for 7 days, and thoroughly characterized. The obtained nanoplatform demonstrated long-term stability and enhanced mechanical properties. Its biocompatibility was confirmed, and its antibacterial and health-promoting effects were attributed to lemon juice-rich in vitamin C, a potent antioxidant with anti-inflammatory properties. The developed system has future potential for use in the biomedical engineering field as a dressing accelerating wound healing.

Vafaei E., Hasani M., Salehi N., Sabbagh Mojaveryazdi F., Hasani S., Enhancement of Biopolymer Film Properties Using Spermidine, Zinc Oxide, and Graphene Oxide Nanoparticles: A Study of Physical, Thermal, and Mechanical Characteristics, Materials, ISSN: 1996-1944, DOI: 10.3390/ma18020225, Vol.18, No.2, pp.225-1-17, 2025

Abstract:
One of the main limitations of biopolymers compared to petroleum-based polymers is their weak mechanical and physical properties. Recent improvements focused on surmounting these constraints by integrating nanoparticles into biopolymer films to improve their efficacy. This study aimed to improve the properties of gelatin–chitosan-based biopolymer layers using zinc oxide (ZnO) and graphene oxide (GO) nanoparticles combined with spermidine to enhance their mechanical, physical, and thermal properties. The results show that adding ZnO and GO nanoparticles increased the tensile strength of the layers from 9.203 MPa to 17.787 MPa in films containing graphene oxide and zinc oxide, although the elongation at break decreased. The incorporation of nanoparticles reduced the water vapor permeability from 0.164 to 0.149 (g.m−2.24 h−1). Moreover, the transparency of the layers ranged from 72.67% to 86.17%, decreasing with higher nanoparticle concentrations. The use of nanoparticles enhanced the light-blocking characteristics of the films, making them appropriate for the preservation of light-sensitive food items. The thermal properties improved with an increase in the melting temperature (Tm) up to 115.5 °C and enhanced the thermal stability in the nanoparticle-containing samples. FTIR analysis confirmed the successful integration of all components within the films. In general, the combination of gelatin and chitosan, along with ZnO, GO, and spermidine, significantly enhanced the properties of the layers, making them stronger and more suitable for biodegradable packaging applications.

Keywords:
nanocomposite,gelatin,chitosan,zinc oxide,graphene oxide

Zargarian S., Salvio S., Javier S., Zuppiroli L., Lanzi M., Ruiz-Molina D., Pierini F., Light-Activated Superhydrophobicity of Sustainable Micro-Structured Spent Coffee Grounds-Based Interfaces via Fatty Acids Modulation, ChemSusChem, ISSN: 1864-5631, DOI: 10.1002/cssc.202402254, pp.e202402254-1-14, 2025

Abstract:
The global consumption of coffee results in the disposal of vast amounts of spent coffee grounds (SCG), posing significant environmental challenges. Herein, we address this issue by developing an innovative, eco-friendly method to achieve superhydrophobicity using SCG. Repurposing this abundant biowaste, we developed a sustainable approach that avoids the use of harsh chemicals and energy-intensive processes typically associated with conventional methods. Our procedure involves wet ball milling of SCG in ethanol to produce microparticles, followed by electrospraying to create a micro-structured interface. A mild annealing treatment at 90 °C successfully transformed the SCG interface from hydrophilic to superhydrophobic, reaching a contact angle of approximately 151° and a rolling-off angle of 8°. The resultant interface exhibited remarkable self-cleaning properties, effectively repelling various liquids. XPS analysis revealed that the migration of fatty acids to the surface during annealing played a crucial role in lowering surface energy, thereby driving the hydrophilic-to-superhydrophobic transition. Furthermore, we demonstrated that solar-induced heating can effectively activate the same superhydrophobic properties, providing a practical and energy-efficient alternative to traditional thermal treatments. This method illustrates the role of light-activated fatty acid modulation in achieving superhydrophobicity and highlights the potential of SCG biowaste as a valuable resource for sustainable material applications.

Pruchniewski M., Strojny-Cieślak B., Nakielski P., Zawadzka K., Urbańska K., Rybak D., Zakrzewska A., Grodzik M., Sawosz E., Electrospun poly-(L-lactide) scaffold enriched with GO-AuNPs nanocomposite stimulates skin tissue reconstruction via enhanced cell adhesion and controlled growth factors release, MATERIALS AND DESIGN, ISSN: 0264-1275, DOI: 10.1016/j.matdes.2025.113713, Vol.251, pp.113713-1-18, 2025

Abstract:
The disruption of homeostasis in the tissue microenvironment following skin injury necessitates the provision of a supportive niche for cells to facilitate the restoration of functional tissue. A meticulously engineered cell-scaffold biointerface is essential for eliciting the desired cellular responses that underpin therapeutic efficacy. To address this, we fabricated an electrospun poly-(L-lactide) (PLLA) cell scaffold enriched with graphene oxide (GO) and gold nanoparticles (AuNPs). Comprehensive characterization assessed the scaffolds’ microstructural, elemental, thermal, and mechanical properties. In vitro investigations evaluated the biocompatibility, adhesive and regenerative capabilities of the scaffolds utilizing human keratinocytes (HEKa), fibroblasts (HFFF2), and reconstructed epidermis (EpiDerm™) models. The results demonstrated that the incorporation of the GO-Au composite substantially altered the nanotopography and mechanical properties of the PLLA fibers. Cells effectively colonized the PLLA + GO-Au scaffold while preserving their structural morphology. Furthermore, PLLA + GO-Au treatment resulted in increased epidermal thickness and reduced tissue porosity. The scaffold exerted a significant influence on actin cytoskeleton architecture, facilitating cell adhesion through the upregulation of integrins, E-cadherin, and β-catenin. Keratinocytes exhibited enhanced secretion of growth factors (AREG, bFGF, EGF, EGF R), while fibroblast secretion remained stable. These findings endorse the scaffold’s potential for regulating cellular fate and preventing hypertrophic tissue formation in skin tissue engineering.

Keywords:
Wound healing,Electrospun fibers,Graphene oxide,Gold nanoparticles,Proregenerative cell scaffold

Olivos Ramirez G., Cofas Vargas L. F., Tobias M., Poma Bernaola A. M., Conformational and Stability Analysis of SARS-CoV-2 Spike Protein Variants by Molecular Simulation, Pathogens, ISSN: 2076-0817, DOI: 10.3390/pathogens14030274, Vol.14, No.274, pp.1-19, 2025

Abstract:
We performed a comprehensive structural analysis of the conformational space of several spike (S) protein variants using molecular dynamics (MD) simulations. Specifically, we examined four well-known variants (Delta, BA.1, XBB.1.5, and JN.1) alongside the wild-type (WT) form of SARS-CoV-2. The conformational states of each variant were characterized by analyzing their distributions within a selected space of collective variables (CVs), such as inter-domain distances between the receptor-binding domain (RBD) and the N-terminal domain (NTD). Our primary focus was to identify conformational states relevant to potential structural transitions and to determine the set of native contacts (NCs) that stabilize these conformations. The results reveal that genetically more distant variants, such as XBB.1.5, BA.1, and JN.1, tend to adopt more compact conformational states compared to the WT. Additionally, these variants exhibit novel NC profiles, characterized by an increased number of specific contacts distributed among ionic, polar, and nonpolar residues. We further analyzed the impact of specific mutations, including T478K, N500Y, and Y504H. These mutations not only enhance interactions with the human host receptor but also alter inter-chain stability by introducing additional NCs compared to the WT. Consequently, these mutations may influence the accessibility of certain protein regions to neutralizing antibodies. Overall, these findings contribute to a deeper understanding of the structural and functional variations among S protein variants.

Keywords:
Molecular Dynamics, Conformational space, Native contact map, Probability states, Collective variables, Protein stability, SARS-CoV-2

Nabavian Kalat M., Ziai Y., Dziedzic K., Gradys A. D., Urbański L., Zaszczyńska A., Andrés Díaz L., Kowalewski Z. L., Experimental evaluation of build orientation effects on the microstructure, thermal, mechanical, and shape memory properties of SLA 3D-printed epoxy resin, EUROPEAN POLYMER JOURNAL, ISSN: 0014-3057, DOI: 10.1016/j.eurpolymj.2025.113829, Vol.228, pp.113829-1-18, 2025

Abstract:
Additive manufacturing (AM) methods, popularly known as 3D printing technologies, particularly the pioneering laser stereolithography (SLA), have revolutionized the production of complex polymeric components. However, challenges such as anisotropy, resulting from the layer-by-layer construction method, can affect the thermomechanical properties and dimensional stability of 3D-printed objects. Although anisotropy in SLA 3D printing is often overlooked due to the high precision of this technique, its impact on the properties and structural performance of the 3D-printed prototype becomes more significant when printing small devices designed for precise micro-mechanisms. This experimental study investigates the impact of the chosen printing surface – a less explored factor – on the performance of SLA 4D-printed thermo-responsive shape memory epoxy (SMEp) specimens. Two identical dog-bone specimens were printed from two distinct surfaces: edge and flat surface, to examine how variations in surface area and quantity of layers influence the microstructure, thermal behavior, mechanical properties, and shape memory performance. The results of this experimental investigation reveal that specimens printed from the edge, with a higher number of layers and smaller surface area, exhibit superior interlayer bonding, tensile strength, dimensional stability, and shape recovery efficiency compared to those printed from the flat surface. Conversely, specimens with fewer, larger layers demonstrated greater elongation and thermal expansion but reduced structural integrity and shape recovery performance. These results highlight the importance of experimentally investigating how different build orientations affect the properties and performance of SLA 3D-printed materials, especially before designing and employing them in applications demanding high precision and reliability.

Keywords:
Additive manufacturing, Laser stereolithography, Shape memory polymers, Materials processing, Anisotropy, Printing orientation

Haghighat Bayan M., Kosik-Kozioł A., Zuzanna Joanna K., Zakrzewska A., Lanzi M., Nakielski P., Pierini F., Gold Nanostar-Decorated Electrospun Nanofibers Enable On-Demand Drug Delivery, Macromolecular Rapid Communications, ISSN: 1022-1336, DOI: 10.1002/marc.202500033, pp.2500033-1-10, 2025

Abstract:
This study explores the development of a photo-responsive bicomponent electrospun platform and its drug delivery capabilities. This platform is composed of two polymers of poly(lactide-co-glycolide) (PLGA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). Then, the platform is decorated with plasmonic gold nanostars (Au NSs) that are capable of on-demand drug release. Using Rhodamine-B (RhB) as a model drug, the drug release behavior of the bi-polymer system is compared versus homopolymer fibers. The RhB is incorporated in the PHBV part of the platform, which provides a more sustained drug release, both in the absence and presence of near-infrared (NIR) irradiation. Under NIR exposure, thermal imaging reveals a notable increase in surface temperature, facilitating enhanced drug release. Furthermore, the platform demonstrates on-demand drug release upon multiple NIR irradiation cycles. This platform offers a promising approach for stimuli-responsive drug delivery, making it a strong candidate for on-demand therapy applications.

Ramírez-Cortés Sara A., Durán-Vargas A., Rauda-Ceja Jesús A., Mendoza-Espinosa P., Cofas Vargas L.F., Cruz-Rangel A., Pérez-Carreón Julio I., García-Hernandez E., Targeting human prostaglandin reductase 1 with Licochalcone A: Insights from molecular dynamics and covalent docking studies, Biophysical Chemistry, ISSN: 0301-4622, DOI: 10.1016/j.bpc.2025.107410, Vol.320-321, pp.107410-1-15, 2025

Abstract:
Prostaglandin reductase 1 (PTGR1) is an NADPH-dependent enzyme critical to eicosanoid metabolism. Its elevated expression in malignant tumors often correlates with poor prognosis due to its role in protecting cells against reactive oxygen species. This study explores the inhibitory potential of licochalcone A, a flavonoid derived from Xinjiang licorice root, on human PTGR1. Using molecular dynamics simulations, we mapped the enzyme's conformational landscape, revealing a low-energy, rigid-body-like movement of the catalytic domain relative to the nucleotide-binding domain that governs PTGR1's transition between open and closed states. Simulations of NADPH-depleted dimer and NADPH-bound monomer highlighted the critical role of intersubunit interactions and coenzyme binding in defining PTGR1's conformational landscape, offering a deeper understanding of its functional adaptability as a holo-homodimer. Covalent docking, informed by prior chemoproteomic cross-linking data, revealed a highly favorable binding pose for licochalcone A at the NADPH-binding site. This pose aligned with a transient noncovalent binding pose inferred from solvent site-guided molecular docking, emphasizing the stereochemical complementarity of the coenzyme-binding site to licochalcone A. Sequence analysis across PTGR1 orthologs in vertebrates and exploration of 3D structures of human NADPH-binding proteins further underscore the potential of the coenzyme-binding site as a scaffold for developing PTGR1-specific inhibitors, positioning licochalcone A as a promising lead compound.

Keywords:
Leukotriene B4 dehydrogenase,NADPH-dependent enzyme,Molecular dynamics simulation,Covalent inhibition,Specific target for cancer therapy

Krysiak Z., Rybak D., Kurniawan T., Zakrzewska A., Pierini F., Light-Driven Structural Detachment and Controlled Release in Smart Antibacterial Multilayer Platforms, Macromolecular Materials and Engineering, ISSN: 1438-7492, DOI: 10.1002/mame.202400462, pp.2400462-1-9, 2025

Abstract:
Smart materials, especially light-responsive, have become a key research area due to their tunable properties. It is related to the ability to undergo physical or chemical changes in response to external stimuli. Among them, photothermal responsive materials have attracted great interest. This study focuses on the development of a multilayer system (MS) consisting of benzophenone-modified polydimethylsiloxane (PDMS) ring and a thermo-responsive core made of poly(N-isopropylacrylamide-co-N-isopropylomethacrylamide) (P(NIPAAm-co-NIPMAAm)), gelatin, and gelatin methacrylate (GelMA). The system utilizes the thermal sensitivity of P(NIPAAm-co-NIPMAAm) and the photothermal effect of gold nanorods (AuNRs) to achieve an on-demand controlled release mechanism within 6 min of near-infrared (NIR) light irradiation. The mechanical properties investigated in the compression test show significant improvement in MS, reaching 60 times greater value than the material without a PDMS ring. In addition, NIR irradiation for 15 min activated the antimicrobial properties, eliminating 99.9% of E. Coli and 100% of S. Aureus, thus presenting pathogen eradication. This platform provides a versatile methodology for developing next-generation smart materials, advanced delivery mechanisms, and multifunctional nanostructured composites. This work highlights the potential of photosensitive materials to revolutionize the field of soft robotics, optics and actuators, and on-demand systems by providing precise control over release dynamics and improved material properties.

Zargarian S., Rinoldi C., Ziai Y., Zakrzewska A., Fiorelli R., Gazińska M., Marinelli M., Majkowska M., Hottowy P., Mindur B., Czajkowski R., Kublik E., Nakielski P., Lanzi M., Kaczmarek L., Pierini F., Chronic Probing of Deep Brain Neuronal Activity Using Nanofibrous Smart Conducting Hydrogel-Based Brain–Machine Interface Probes, Small Science, ISSN: 2688-4046, DOI: 10.1002/smsc.202400463, pp.2400463-1-19, 2025

Abstract:
The mechanical mismatch between microelectrode of brain–machine interfaces (BMIs) and soft brain tissue during electrophysiological investigations leads to inflammation, glial scarring, and compromising performance. Herein, a nanostructured, stimuli-responsive, conductive, and semi-interpenetrating polymer network hydrogel-based coated BMIs probe is introduced. The system interface is composed of a cross-linkable poly(N-isopropylacrylamide)-based copolymer and regioregular poly[3-(6-methoxyhexyl)thiophene] fabricated via electrospinning and integrated into a neural probe. The coating's nanofibrous architecture offers a rapid swelling response and faster shape recovery compared to bulk hydrogels. Moreover, the smart coating becomes more conductive at physiological temperatures, which improves signal transmission efficiency and enhances its stability during chronic use. Indeed, detecting acute neuronal deep brain signals in a mouse model demonstrates that the developed probe can record high-quality signals and action potentials, favorably modulating impedance and capacitance. Evaluation of in vivo neuronal activity and biocompatibility in chronic configuration shows the successful recording of deep brain signals and a lack of substantial inflammatory response in the long-term. The development of conducting fibrous hydrogel bio-interface demonstrates its potential to overcome the limitations of current neural probes, highlighting its promising properties as a candidate for long-term, high-quality detection of neuronal activities for deep brain applications such as BMIs.