Hilda Esperanza Esparza-Ponce

Dr. Hilda Esperanza Esparza-Ponce

Physics of Materials, Centro de Investigación en Materiales Avanzados, Chihuahua City, Mexico
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Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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ABAndrea-Sarahí Balderrama-González
Andrea-Sarahí Balderrama-González
HPHilda Amelia Piñón-Castillo
Hilda Amelia Piñón-Castillo
Claudia Adriana Ramirez ValdespinoClaudia Adriana Ramirez Valdespino
Claudia Adriana Ramirez Valdespino
LMLinda Lucila Lucero Landeros Martinez
Linda Lucila Lucero Landeros Martinez
EBErasmo Orrantia Borunda
Erasmo Orrantia Borunda
Hilda Esperanza Esparza-PonceHilda Esperanza Esparza-Ponce
Hilda Esperanza Esparza-Ponce
Antibiotics are being less effective, which leads to high mortality in patients with infections and a high cost for the recovery of health, and the projections that are had for the future are not very encouraging which has led to consider antimicrobial resistance as a global health problem and to be the object of study by researchers. Although resistance to antibiotics occurs naturally, its appearance and spread have been increasing rapidly due to the inappropriate use of antibiotics in recent decades. A bacterium becomes resistant due to the transfer of genes encoding antibiotic resistance. Bacteria constantly mutate; therefore, their defense mechanisms mutate, as well. Nanotechnology plays a key role in antimicrobial resistance due to materials modified at the nanometer scale, allowing large numbers of molecules to assemble to have a dynamic interface. These nanomaterials act as carriers, and their design is mainly focused on introducing the temporal and spatial release of the payload of antibiotics. In addition, they generate new antimicrobial modalities for the bacteria, which are not capable of protecting themselves. So, nanoparticles are an adjunct mechanism to improve drug potency by reducing overall antibiotic exposure. These nanostructures can overcome cell barriers and deliver antibiotics to the cytoplasm to inhibit bacteria. This work aims to give a general vision between the antibiotics, the nanoparticles used as carriers, bacteria resistance, and the possible mechanisms that occur between them.

29 August 2012 in Discover Nano
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YVYuri V Vorobiev
Yuri V Vorobiev
PHPaul P Horley
Paul P Horley
JHJorge Hernández-Borja
Jorge Hernández-Borja
Hilda Esperanza Esparza-PonceHilda Esperanza Esparza-Ponce
Hilda Esperanza Esparza-Ponce
RRRafael Ramírez-Bon
Rafael Ramírez-Bon
JGJesús González-Hernández
Jesús González-Hernández
This paper is dedicated to study the thin polycrystalline films of semiconductor chalcogenide materials (CdS, CdSe, and PbS) obtained by ammonia-free chemical bath deposition. The obtained material is of polycrystalline nature with crystallite of a size that, from a general point of view, should not result in any noticeable quantum confinement. Nevertheless, we were able to observe blueshift of the fundamental absorption edge and reduced refractive index in comparison with the corresponding bulk materials. Both effects are attributed to the material porosity which is a typical feature of chemical bath deposition technique. The blueshift is caused by quantum confinement in pores, whereas the refractive index variation is the evident result of the density reduction. Quantum mechanical description of the nanopores in semiconductor is given based on the application of even mirror boundary conditions for the solution of the Schrödinger equation; the results of calculations give a reasonable explanation of the experimental data.

1 May 2021 in Dental Materials
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ANAlfredo Nevarez-Rascón
Alfredo Nevarez-Rascón
AHAbel Hurtado-Macias
Abel Hurtado-Macias
Hilda Esperanza Esparza-PonceHilda Esperanza Esparza-Ponce
Hilda Esperanza Esparza-Ponce
MNMartina Nevárez-Rascón
Martina Nevárez-Rascón
JGJesús González-Hernández
Jesús González-Hernández
MYMiguel José. Yacamán
Miguel José. Yacamán

16 December 2021 in Nanomaterials
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SNSofía Navarro-Espinoza
Sofía Navarro-Espinoza
Diana Meza-FigueroaDiana Meza-Figueroa
Diana Meza-Figueroa
RGRoberto Guzmán
Roberto Guzmán
JMJose Alberto Duarte Moller
Jose Alberto Duarte Moller
Hilda Esperanza Esparza-PonceHilda Esperanza Esparza-Ponce
Hilda Esperanza Esparza-Ponce
MPMartin Pedroza-Montero
Martin Pedroza-Montero
A Three-Way Catalyst (TWC) contains a cordierite ceramic monolith coated with a layer of Al2O3, CexZr1−xO2 and platinoids mixture. Under standard operation, the platinoid concentration decreases, exposing the remaining washcoat structure. After that particle release stage, the sintering process follows where the crystalline CexZr1−xO2 solution is broken and begins to separate into ZrO2 and CeO2 phases. ZrO2 is released to the environment as micro and nanoparticles, while a small amount of CeO2 generates a new AlxCe1−xO2 composite. The main effect of Ce capture is the growth in the size of the polycrystal structure from 86.13 ± 16.58 nm to 225.35 ± 69.51 nm. Moreover, a transformation of cordierite to mullite was identified by XRD analysis. Raman spectra showed that the oxygen vacancies (Vö) concentration decreased as CexZr1−xO2 phases separation occurred. The SEM-EDS revealed the incorporation of new spurious elements and microfractures favouring the detachment of the TWC support structure. The release of ultrafine particles is a consequence of catalytic devices overusing. The emission of refractory micro to nanocrystals to the atmosphere may represent an emerging public health issue underlining the importance of implementing strict worldwide regulations on regular TWCs replacement.

13 May 2020 in Energies
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JRJaime Hernández Rivera
Jaime Hernández Rivera
DDDavid Ortega Díaz
David Ortega Díaz
DADiana M Amaya-Cruz
Diana M Amaya-Cruz
Juvenal RodriguezJuvenal Rodriguez
Juvenal Rodriguez
Juan Manuel Olivares RamírezJuan Manuel Olivares Ramírez
Juan Manuel Olivares Ramírez
Hilda Esperanza Esparza-PonceHilda Esperanza Esparza-Ponce
Hilda Esperanza Esparza-Ponce
The research aims were to construct an air-breathing paper-based microfluidic fuel cell (paper-based μ FC) and to evaluated it with different soft drinks to provide energy for their prospective use in portable devices as an emergency power source. First, in a half-cell configuration, cyclic voltammetry showed that glucose, maltose, and fructose had specific oxidation zones in the presence of platinum-ruthenium on carbon (PtRu/C) when they were individual. Still, when they were mixed, glucose was observed to be oxidized to a greater extent than fructose and maltose. After, when a paper-based μ FC was constructed, PtRu/C and platinum on carbon (Pt/C) were used as anode and cathode, the performance of this μ FC was mostly influenced by the concentration of glucose present in each soft drink, obtaining maximum power densities at room temperature of 0.061, 0.063, 0.060, and 0.073 mW cm − 2 for Coca Cola ® , Pepsi ® , Dr. Pepper ® , and 7up ® , respectively. Interestingly, when the soft drinks were cooled, the performance was increased up to 85%. Furthermore, a four-cell stack μ FC was constructed to demonstrate its usefulness as a possible power supply, obtaining a power density of 0.4 mW cm − 2 , using Coca Cola ® as fuel and air as oxidant. Together, the results of the present study indicate an alternative application of an μ FC using soft drinks as a backup source of energy in emergencies.

1 June 2025 in International Journal of Nanomedicine
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RRRosa Isela Ruvalcaba
Rosa Isela Ruvalcaba
Hilda Esperanza Esparza-PonceHilda Esperanza Esparza-Ponce
Hilda Esperanza Esparza-Ponce
RRReyna Reyes-Martínez
Reyna Reyes-Martínez
LMLaura Manjarrez-Nevárez
Laura Manjarrez-Nevárez
VGValente Gómez-Benítez
Valente Gómez-Benítez
HPHilda Amelia Piñón-Castillo
Hilda Amelia Piñón-Castillo
Introduction: This study investigated the incorporation of Amphipterygium adstringens ethanolic extract into the synthesis of copper oxide nanoparticles (CuO+Aa) and evaluates their antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) and carbapenem-resistant Acinetobacter baumannii (CRAB). To assess the impact of the extract, chemically synthesized CuO nanoparticles (CuO-NPs) and the extract alone were also tested. Both CuO-NPs and A. adstringens are known for their antimicrobial properties. Methods: CuO+Aa nanoparticles were synthesized using A. adstringens extract and characterized through Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS), Zeta Potential, Thermogravimetric Analysis (TGA), and X-ray Diffraction (XRD), and compared to CuO-NPs. The influence of the extract was analyzed using Inductively Coupled Plasma Mass Spectroscopy (ICP-MS), UV-Vis, FTIR, Raman, and Nuclear Magnetic Resonance Spectroscopy (NMR). Antibacterial effects were tested using the microdrop technique and biofilm inhibition. Bacterial structural changes were observed via Scanning Electron Microscopy (SEM), and cytotoxicity was measured through hemolysis assays. Results: CuO+Aa nanoparticles were smaller (3.46 nm) than CuO-NPs (5.32 nm). TGA indicated improved thermal degradation in CuO+Aa, suggesting incorporation of organic compounds. XRD revealed a shift from CuO to a mixed CuO-Cu2O phase (75.15%– 24.84%) in CuO+Aa due to the functional groups present in the extract. Antibacterial assays showed that CuO+Aa inhibited MRSA and CRAB by 77% and 49%, respectively, using only 17.5 ppm of copper oxides—significantly lower than CuO-NPs, which required 150 ppm to achieve 96% and 78% inhibition. SEM revealed bacterial surface damage, including roughness, perforations, and cell wall collapse. All treatments showed low cytotoxicity (< 2% hemolysis). Biofilm formation increased by 180% in MRSA and 131% in CRAB. Conclusion: A. adstringens ethanolic extract enhances CuO nanoparticle synthesis, reducing size and maintaining strong antibacterial activity with low toxicity. CuO+Aa represents a promising candidate for future biomedical applications against resistant pathogens.