arXiv subjects

Angel Gonzalez-Lizardo

Publications and source records attributed to Angel Gonzalez-Lizardo.

7 recordsLinked to original sources

arXiv2025

Activation of Polylactic Acid and Polycarbonate Surfaces with Non-Thermal Plasma

Non-thermal plasma (NTP) surface activation has become a powerful and versatile strategy to engineer the interfacial properties of biomedical polymers whose intrinsic hydrophobicity limits their biological performance. In polymers such as polylactic acid (PLA) and polycarbonate (PC), NTP promotes the controlled incorporation of polar functional groups, increases surface energy, modifies dielectric behavior, and generates micro-roughness that collectively enhance protein adsorption and early cell adhesion. This review synthesizes and critically evaluates evidence across four complementary analytical pillars-contact-angle theory, dielectric impedance spectroscopy, FT-IR chemical mapping, and optical microscopy-to construct an integrated framework for interpreting plasma-induced chemical and morphological transformations. The convergence of multimodal results demonstrates that NTP consistently produces chemically active, polar, and moderately textured surfaces that support robust initial cell-material interactions. Furthermore, combining wettability, dielectric, and spectroscopic analysis enables the identification of activation pathways, the assessment of hydrophobic recovery dynamics, and the development of quantitative correlations between dielectric parameters and biological response. However, the literature also reveals key methodological gaps, including the limited use of unified multimodal protocols, insufficient evaluation of temporal stability, and a lack of predictive dielectric-biological models. By articulating these advances and limitations within a unified conceptual scheme, this review provides a roadmap for future research aimed at standardizing characterization workflows and enabling the rational design of next-generation plasma-functionalized biomaterials for tissue-engineering scaffolds, implantable devices, and advanced drug-delivery systems.

physics.plasm-ph↗

arXiv2025

Plasma-Treated Polymeric Biomaterials for Improved Surface and Cell Adhesion

Surface modification of polymeric biomaterials using plasma has emerged as an effective strategy to optimize the cell-material interface without compromising the structural properties of the material. This work presents a critical review of the impact of low-temperature plasma treatment on enhancing cell adhesion, with emphasis on the physicochemical changes induced on the surface of polymers commonly used in biomedical applications. The mechanisms of interaction between reactive plasma species and the polymer surface are analyzed, along with techniques used to introduce hydrophilic functional groups that improve wettability and biocompatibility. Scientific evidence demonstrates that this type of surface modification promotes greater cell spreading, anchorage, and proliferation, making it particularly useful in the design of tissue engineering scaffolds, implantable devices, and vascular prostheses. Finally, current and future trends in the development of smart plasma-functionalized biomaterials are discussed, highlighting their role in regenerative medicine.

physics.plasm-ph↗

arXiv2025

Catalytic Nanoparticles: An Introduction

This study explores the transformative potential of nanocatalysts, emphasizing their pivotal role in catalysis and material science. Key synthesis techniques, including chemical reduction and hybrid methods, are highlighted for their ability to control particle size and enhance stability. Applications in environmental remediation, fuel quality improvement, and renewable energy showcase the broad impact of nanocatalysts. Despite challenges in scalability and stabilization, advancements in bimetallic configurations and electro-steric approaches demonstrate significant progress. This research underscores nanocatalysts' promise for sustainable industrial processes and global challenges.

cond-mat.mtrl-sci↗

arXiv2024

Solid-State Diffusion: An Introduction

This research explores an introduction to solid-state diffusion, focusing on its importance in materials engineering. It examines vacancy and interstitial diffusion mechanisms, the application of Fick's laws, and their impact on processes such as phase precipitation and recrystallization in metals and alloys. Additionally, it addresses its relevance in grain growth, diffusion welding, and sintering, which are critical processes to improve the properties of materials with engineering applications in various areas such as biomedical, electrical, and chemistry.

cond-mat.mtrl-sci↗

arXiv2024

Sterilization of Bacteria with Low-Pressure Low-Temperature Plasma Discharge

The study investigates the effectiveness of using low-pressure oxygen plasma, generated by microwave discharge, to sterilize bacterial spores of Bacillus Stearothermophilus and Bacillus Subtilis. Plasma, a highly ionized state of matter consisting of positive ions and free electrons, is created by applying high temperatures or accelerating electrons through an electric field. This method provides an innovative alternative to traditional sterilization techniques, particularly beneficial for heatsensitive materials. In the experiments, microwave at 2.45 GHz with 1000 W and 500 W intensities (990 W and 495 W) were applied in a vacuum chamber at a pressure of $10^{-3}$ Torr. Spores were exposed to the plasma using two types of holders: Petri dishes and centrifuge tubes, for 1, 5, and 10 minutes. The findings revealed that direct exposure to oxygen plasma at a 1000 W microwave power effectively inactivated spores in Petri dishes, especially for B. Subtilis. Conversely, centrifuge tubes did not allow sufficient plasma exposure, leading to the survival of bacteria posttreatment. The inactivation process involves UV induced DNA damage and the erosion of spores' protective layers by oxygen radicals. The study concludes that low-pressure oxygen plasma is a promising technology for sterilizing heat-sensitive materials. Optimal conditions identified include a 1000 W microwave power and exposure times of at least 5 minutes for B. Stearothermophilus and 1 minute for B. Subtilis. Petri dishes proved more effective than centrifuge tubes due to the closer and more direct plasma contact. This method offers a safe and efficient alternative to traditional sterilization techniques, with significant potential for applications in the sterilization of medical devices and other delicate materials.

physics.plasm-ph↗

arXiv2024

Water Purification Via Plasma

Water purification via plasma is considered a healthy, effective alternative to traditional water purification systems due to the lack of harmful chemical additives that traditional purification systems use. A reactor capable of eliminating bacteria colonies from contaminated water using plasma discharge was designed and tested. Materials and reactor parameters are discussed in this paper. It was confirmed that glow discharge plasma in water creates oxidants, eliminating bacteria colonies.

physics.plasm-ph↗

arXiv2016

Simulation of a Hyperbolic Field Energy Analyzer

Energy analyzers are important plasma diagnostic tools with applications in a broad range of disciplines including molecular spectroscopy, electron microscopy, basic plasma physics, plasma etching, plasma processing, and ion sputtering technology. The Hyperbolic Field Energy Analyzer (HFEA) is a novel device able to determine ion and electron energy spectra and temperatures. The HFEA is well suited for ion temperature and density diagnostics at those situations where ions are scarce. A simulation of the capacities of the HFEA to discriminate particles of a particular energy level, as well as to determine temperature and density is performed in this work. The electric field due the combination of the conical elements, collimator lens, and Faraday cup applied voltage was computed in a well suited three-dimensional grid. The field is later used to compute the trajectory of a set of particles with a predetermined energy distribution. The results include the observation of the particle trajectories inside the sensor, the comparison of the input energy distribution to the energy distribution of the particles captured by the Faraday cup, and the IV characteristic at the Faraday cup, using the voltage sweep at the conical elements as the abscissa.

physics.plasm-ph↗