Mayra Angelica Alvarez Lemus
@ujat.mx
Professor Researcher -Academic Division of Engineering and Architecture
Universidad Juárez Autónoma de Tabasco
RESEARCH, TEACHING, or OTHER INTERESTS
Chemistry, Catalysis, Spectroscopy, Water Science and Technology
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
K. Macías-Collado, , L.T. Ballesteros-Rozo, V.W. Velázquez-Vázquez, D.M. Frías-Márquez, R. López-González, and M.A. Alvarez-Lemus
Universidad Autonoma Metropolitana
Jesús Eduardo de la Cruz‐de los Santos, David Salvador García‐Zaleta, Cecilia Encarnación‐Gómez, Zurisadai Martínez‐Corona, Rosendo López‐González, Mayra Angélica Álvarez‐Lemus, Carlos Mario Morales‐Bautista, D. Palma‐Ramírez, and Armando Reyes‐Montero
Wiley
AbstractBACKGROUNDThe degradation of organic pollutants, such as p‐cresol, is a challenge for natural mechanisms, and semiconductors are useful as photocatalysts to restore water quality. This work investigated the effects of neodymium (Nd) and niobium (Nb) doping on the structural and photocatalytic properties of titania (TiO2) under ultraviolet (UV) irradiation.RESULTSX‐ray diffraction (XRD) results displayed the formation of anatase, TiO2(B) and rutile phases on the Nd/TiO2 and Nb/TiO2 compounds. The Rietveld analysis estimated the composition of phases, as well as the crystal size for each crystalline phase in the samples (<43 nm). The crystal sizes and morphology of the powders were observed using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Energy dispersive spectroscopy (EDS) and X‐ray spectroscopy (XPS) analysis confirmed the presence of Nd and Nb dopants in the TiO2‐based photocatalysts. Nitrogen adsorption/desorption isotherms results revealed pore sizes between 5 and 11 nm, as well as surface area values up to ~81 m2 g−1. The diverse compounds showed excellent removal efficiency of p‐cresol under UV light (10–30% faster than commercial TiO2‐P25).CONCLUSIONSThis synthesis method favored the incorporation of Nd and Nb dopants in the TiO2 structure. Nd/TiO2 specimens showed higher photocatalytic response than Nb/TiO2 samples, possibly as a result of the synergic effects between phases [anatase and TiO2(B)], higher surface area values (≤ ~80.47 m2 g−1), as well as the nature of dopant. Photocatalysts with better photocatalytic performance demonstrated good degradation rate after 20 h. © 2024 Society of Chemical Industry (SCI).
Rosendo López González, Mirian Hernández Gutiérrez, Ruth Lezama García, Sergio Alberto Gómez Cornelio, Carlos Lobato, Abraham Gómez‐Rivera, Patricia Quintana Owen, and Mayra Angélica Alvarez Lemus
Wiley
AbstractBACKGROUNDZinc oxide nanoparticles (ZnO NPs) were obtained through precipitation synthesis, using aqueous water hyacinth leaf extract (Eichhornia crassipes) under alkaline conditions. The effect of the extract on the physicochemical and antimicrobial properties of the ZnO was evaluated starting from concentrated extract (labeled as E100) and performing two dilutions of this concentrated extract at 50% and 25% in water (E50, and E25).RESULTSThe FTIR spectra revealed strong peaks at ≈3440 cm−1, corresponding to vibrations from OH stretching, and medium‐intense peaks at 1384 and 1327 cm−1, assigned to CC, COOH and COC vibrations, which are related to the presence of the extract; a weak band at 884 cm−1 and a broad band in the region below 600 cm−1 indicate the presence of ZnO. The hydrodynamic size of the ZnOE100, ZnOE50 and ZnOE25 samples were 202, 244 and 313 nm, respectively. No significant variations on the Eg value were observed. Field emission scanning electron microscopy images showed that the ZnO NPs have triangular‐like shapes and agglomeration of the NPs synthesized for the ZnOE25 sample. The minimum inhibitory concentration (MIC) of the ZnO NPs showed no significant effects related to the concentration the plant extract used.CONCLUSIONSVariations in particle size and zeta potential can be introduced in ZnO by varying the content of the extract; the presence of organic groups from the extract, along with a positive zeta potential value, can promote the bactericide effect of ZnO nanomaterials prepared by bio‐assisted synthesis. © 2024 Society of Chemical Industry (SCI).
Mayra A. Alvarez Lemus, Ariana Lizbeth Jiménez Rodríguez, Cinthia García Mendoza, Ruth Lezama García, David S. García Zaleta, Dora M. Frías Márquez, Patricia Quintana Owen, and Rosendo López González
Wiley
AbstractBackgroundIn this work, we investigated the effect of nickel on the photocatalytic properties of TiO2 nanostructures. The photocatalysts were obtained in a two‐stage procedure. First, the sol–gel method was used for obtaining TiO2 and Ni‐TiO2 at 1.0 wt% of Ni, which was then followed by hydrothermal treatment under highly alkaline conditions with NaOH at 110°C.ResultsThe obtained powders were thermally treated at 400°C. The main crystalline phase was anatase for all the samples, and a lower Eg value was estimated for the Ni/TiO2 sample (3.13 eV). The specific BET areas were obtained from N2 isotherms at 77 K, being 141 and 153 m2/g for pure TiO2 and 1.0% Ni‐TiO2 samples, respectively. Scanning electron microscopy confirmed the rod shape of the particles with diameters between 10 and 20 nm and length between 100 and 400 nm. X‐ray photoelectron spectroscopy analysis showed the presence of oxygen vacancies and surface hydroxyl oxygen species in all samples, but in a higher ratio for the Ni/TiO2‐HT‐400 sample. The photocatalytic test was performed using two different radiation sources: 254 nm and a simulated solar lamp (300 W), for the photoreduction of 4‐nitrophenol to 4‐aminophenol, which was followed by UV–vis spectroscopy.ConclusionsThe Ni/TiO2‐HT‐400 sample showed a high efficiency, reaching 100% reduction after 15 min (simulated solar radiation) and 40 min (λ = 254 nm) after the first cycle, while for the second cycle these values decreased to 63% and 78%, respectively. The increase in the photocatalytic reduction of TiO2 nanostructures was achieved mainly through the presence of oxygen vacancies along with the decrease in electron–hole recombination. © 2023 Society of Chemical Industry (SCI).
Rosendo López González, Orbelin de la Fuente, Ruth Lezama García, Melina del Carmen Uribe López, Patricia Quintana Owen, María Carmen Hidalgo López, and Mayra Angélica Alvarez Lemus
Wiley
AbstractBACKGROUNDPhenol and its derivatives are considered toxic compounds, even at low concentrations. Their accumulation in water effluents has become a serious problem that could be resolved by using zinc oxide (ZnO)‐based photocatalysts.RESULTSZnO nanoparticles were synthesized through the precipitation method, using zinc nitrate and sodium carbonate as reagents. The as‐synthesized powder was calcined for 4 h at 500 °C (2° C min−1). X‐Ray diffraction analysis confirmed a hexagonal crystalline phase (wurtzite) with an average crystallite size of 38 nm. The Kubelka‐Munk method was used to determine a band gap of 3.27 eV through UV–Vis diffuse reflectance spectrum and a Brunauer‐Emmett‐Teller (BET) specific area of 12 m2 g−1 was obtained from N2 adsorption analysis. The photocatalytic activity of ZnO was evaluated under visible light (300 W) lamp, with 1 mg mL−1 of photocatalyst and using phenol solutions at different concentrations of 5, 10, 25, and 50 ppm; the obtained degradation percentages were 98%, 97%, 94%, and 71%, respectively. Three cycles were performed with the ZnO used in the reactions with phenol at 5 and 50 ppm, decreasing the degraded percentages to 87% and 65%, respectively. The generation of hydroxyl radicals was estimated for the ZnO and ZnO samples after three cycles by means of fluorescence spectroscopy analysis. It was observed that the first‐used ZnO material generated a significant amount of hydroxyl radicals.CONCLUSIONWhen compared to ZnO after three cycles of reaction, the amount of generated hydroxyl radicals decreased. It was observed that the higher the amount of phenol, the lower the generation of hydroxyl radicals after reuse; this was probably due to the presence of some adsorbed by‐products of the photocatalytic reaction on the surface of ZnO, as the FTIR spectrum of the post‐reaction sample showed. © 2023 Society of Chemical Industry (SCI).
J.C. Castillo-Rodríguez, F. Tzompantzi, C. Tzompantzi-Flores, M.E. Velásquez-Torres, R. Gómez, C.E. Santolalla-Vargas, M.A. Álvarez Lémus, E. Ramos-Ramírez, and G. Del Ángel Montes
Elsevier BV
Cinthia García‐Mendoza, Williams Eduardo Sánchez Rivera, Mayra A Alvárez‐Lemus, Gabriela Jácome‐Acatitla, Dora María Frías Márquez, and Rosendo López‐González
Wiley
AbstractBACKGROUNDThe use of organic molecules to improve the performance of semiconductors (such as using ZnS in hydrogen production) has been widely studied. This work studies the formation of a photocatalyst formed by ZnS/ZnO anchored to an organic molecule (hexamethylenediamine) under different amounts of the organic material and its performance in hydrogen production is evaluated.RESULTSThe materials were synthesized by the precipitation method, forming ZnS/ZnO composite, 3HMDA and 9HMDA materials showed flower‐like structure. The 6HMDA material showed a nanotube like structure and high surface area . Likewise, the anchoring of the organic material forming stacked lamellae is confirmed. Regarding hydrogen production, the most active material was 6HMDA, which showed an excellent performance, producing 3281 μmoles after 5 h of reaction with a production rate of 12 916 μmoles h−1 g‑1; 6HMDA increased the effectiveness with respect to ZnS by a factor of 4.3, while the 9HMDA material increased it 1.5 times.CONCLUSIONThe organic material and the ZnS/ZnO work together to improve the photocatalytic activity and stability of the material, increasing hydrogen production under UV light. These results show that it is possible to obtain an efficient material with excellent photocatalytic performance by a relatively simple synthesis method. © 2022 Society of Chemical Industry (SCI).
Diego Hernández‐Acosta, Gabriela Jácome‐Acatitla, Cinthia García‐Mendoza, Mayra Álvarez‐Lemus, Rosendo López‐Gónzalez, and Francisco Tzompantzi
Wiley
AbstractBACKGROUND4‐chlorophenol is one of the most commonly used products in industrial processes. This compound exhibits a high chemical stability that makes its removal from wastewater difficult by conventional methods. Although diverse methods have been applied for its elimination, photocatalysis is one of the only techniques with several advantages, such as nontoxic by‐products and mild reaction conditions. One of the goals in improving this remedial technology is the development of materials with adequate physicochemical properties that enhance the catalytic activity and thus allow the complete degradation of the pollutant or its elimination in shorter periods of time.RESULTSMagnetic ZnFe2O4 catalysts were prepared by the hydrothermal method using as complexing agents oxalic, citric, and tartaric acids. The specific surface areas of the samples were between 23.938 and 48.058 m2/g and the band gap energies were in the range of 1.55–1.90 eV. These materials were evaluated under UV light irradiation (254 nm, 2 W) for the photodegradation of 4‐chlorophenol. All samples showed photodegradation efficiencies around 60% after three hours of reaction at pH 3.CONCLUSIONThe results confirmed that the complexing agents have an influence on the physicochemical properties of the synthesized catalysts. The catalyst synthesized using citric acid was the only one to exhibit a significant activity at the three pH levels (3, 5, 6). The above can be attributed to the fact that this material presents the lowest bandgap and crystallite size values along with the largest specific surface area of all the synthesized samples. © 2022 Society of Chemical Industry (SCI).
José M. Osorio Jiménez, Rosendo López González, Cinthia García Mendoza, Ignacio Cuauhtémoc-López, Mayra A. Alvarez Lemus, and Getsemani Morales Mendoza
Sociedad Quimica de Mexico, A.C.
Abstract. The removal of pollutants derived from oil industry takes relevance in industrial zones moreover if some of them has been reported as carcinogenic and detrimental to public health at low concentrations. In this research was explored the synergic effect between adsorption of the hydrocarbon’s benzene and naphthalene and its photodegradation under visible irradiation. The capabilities of system graphene oxide (GO) - bismuth oxide (Bi2O3) were evaluated both as adsorbent and active semiconductor for the removal of benzene and naphthalene in aqueous media. The content ratio between materials was changed to evaluate the effect on its properties. The X-ray diffraction indicates the stability of α-bismuth oxide which is known as an efficient photocatalyst meanwhile Raman spectroscopy indicates the successfully obtaining of detached layer of graphene oxide. The energy band gap of the most photoactive composites materials indicates an increase comparing with bare GO, this increase is favorable to decrease the high electron transfer in its surface. The removal efficiency of benzene and naphthalene indicate the predominance of the adsorption process; the highest elimination was for naphthalene removing 73 percent of the pollutant in aqueous media. The results indicate the system as a promising alternative for the elimination of contaminants derived from the hydrocarbons industry when present in aqueous media. Resumen. La remoción de contaminantes derivados de industria del petróleo toma relevancia in zonas industriales sobre todo porque varios de ellos han sido reportados como cancerígenos y en general perjudiciales para la salud pública aún en bajas concentraciones. En esta investigación se explora el efecto sinérgico entre la adsorción de los hidrocarburos benceno y naftaleno y su fotodegradación bajo irradiación visible. Se evaluó la capacidad del sistema óxido de grafeno (GO)-óxido de bismuto (Bi2O3) como adsorbente y semiconductor activo para la eliminación de benceno y naftaleno en medio acuoso. Se cambió la relación de contenido entre materiales propuestos para evaluar el efecto sobre sus propiedades fisicoquímicas. De los resultados, la difracción de rayos X indica la estabilidad del α- óxido de bismuto, conocido como un fotocatalizador eficiente, mientras que por espectroscopia Raman se indica la obtención de capa separadas de óxido de grafeno. La energía de banda prohibida de los materiales fotoactivos indica un aumento en comparación con el GO puro, este aumento se considera favorable para disminuir la alta transferencia de electrones en su superficie. La eficiencia en la remoción de benceno y naftaleno indica el predominio del proceso de adsorción; la mayor eliminación fue para el naftaleno eliminándose el 73 por ciento del contaminante en medio acuoso. Los resultados señalan al sistema como una alternativa prometedora para la eliminación de contaminantes derivados de la industria de los hidrocarburos en medio acuoso.
Lisbeth Almeida Ramón, Erick N. de la Cruz Hernández, Rosendo López González, María Fernanda Hernández Landero, Patricia Quintana Owen, Cinthia García Mendoza, Getsemani Morales Mendoza, and Mayra Angélica Alvarez Lemus
Springer Science and Business Media LLC
Cinthia GarcÍa-Mendoza, Mayra Angélica Alvarez-Lemus, Rosendo López-González, Dora María Frias Márquez, and Gabriela Jácome-Acatitla
Trans Tech Publications, Ltd.
Photocatalytic reduction of 4-nitrophenol is one of the most promising methods to remove this hazardous pollutant from wastewaters and generated a raw compound widely use in industrial processes. In the present work, three Bi2S3/TiO2 catalysts with different Bi2S3 content, were synthesized by a hydrothermal method. The materials were characterized by XRD, X-ray fluorescence, physisorption of N2, HRTEM, UV-Vis reflectance spectroscopy and zeta potential measurements. The catalytic activity of the synthesized materials was tested in the photoreduction of 4-nitrophenol in aqueous medium. Although the results indicate the formation of heterojunction for all the samples, the physicochemical properties of each material depend on the Bi2S3 content. The material with 6%wt of Bi2S3 exhibit the major catalytic activity, reducing 80% of the target molecule within 60 minutes of reaction.
Rudy Trejo-Tzab, Alejandro Avila-Ortega, Patricia Quintana-Owen, Ricardo Rangel, and Mayra Angélica Álvarez-Lemus
MDPI AG
In the present work, N-TiO2−x/Pt was synthesized using a homemade nitrogen plasma (AC) discharge system. The overall procedure use of low-power nitrogen plasma (100 watts) with 1 and 2 h of plasma discharge to successfully impregnate platinum nanoparticles on P25 titanium dioxide. The obtained samples were characterized using X-ray diffraction (XRD), UV–Vis diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron microscopy (HRTEM). The results reveal the incorporation of metallic Pt up to 2.9% on the surface of TiO2 by increasing the duration of plasma discharge by up to two hours with a constant power of 100 watts. Likewise, the incorporation of nitrogen atoms into a lattice crystal was also favored, confirming a direct relationship between the amount of Pt and nitrogen atoms introduced in TiO2 as a function of the duration of plasma treatment. By characterizing nanoparticles loaded on a N-TiO2−x/Pt surface, we show that joined platinum nanoparticles have two different patterns, and the boundary between these two regions coalesces. The results demonstrate that the use of nitrogen plasma to impregnate platinum nanoparticles on the surface of TiO2 to obtain N-TiO2−x/Pt allows wide and relevant physics and chemistry applications.
Daniela J. Hernández-Castillo, Erick Natividad de la Cruz Hernández, Dora M. Frías Márquez, Richard D. Tilley, Lucy Gloag, Patricia Quintana Owen, Rosendo López González, and Mayra A. Alvarez Lemus
MDPI AG
In this work, a pH-responsive drug-carrier based on chitosan-silica nanospheres was developed as a carrier for Albendazole (ABZ), a poorly water-soluble anthelmintic drug. Spherical silica nanoparticles were obtained by Stöber method and further etched to obtain mesoporous particles with sizes ranging from 350 to 400 nm. The specific BET area of nanoparticles increased from 15 m2/g to 150 m2/g for etched silica, which also exhibited a uniform pore size distribution. X-ray powder diffraction showed the presence of amorphous phase of silica and a low-intensity peak attributed to ABZ for the drug-loaded nanoparticles. A uniform layer of chitosan was obtained ranging from 10 to 15 nm in thickness due to the small concentration of chitosan used (0.45 mg of chitosan/mg of SiO2). The in vitro evaluation of hybrid nanoparticles was performed using four cervical cancer cell lines CaSki, HeLa, SiHa and C33A, showing a significant reduction in cell proliferation (>85%) after 72 h. Therefore, we confirmed the encapsulation and bioavailability of the drug, which was released in a controlled way, and the presence of chitosan delayed the release, which could be of interest for the development of prolonged release drug delivery systems.
M.C. Uribe-López, M.C. Hidalgo-López, R. López-González, D.M. Frías-Márquez, G. Núñez-Nogueira, D. Hernández-Castillo, and M.A. Alvarez-Lemus
Elsevier BV
Waldo Roberto Gallegos-Pérez, Ana Cecilia Reynosa-Martínez, Claudia Soto-Ortiz, Mayra Angélica Álvarez-Lemus, Joaquín Barroso-Flores, Verónica García Montalvo, and Eddie López-Honorato
Elsevier BV
Lucy Gloag, Milad Mehdipour, Marina Ulanova, Kevin Mariandry, Muhammad Azrhy Nichol, Daniela J. Hernández-Castillo, Jeff Gaudet, Ruirui Qiao, Ji Zhang, Melanie Nelson,et al.
Royal Society of Chemistry (RSC)
Zero valent iron core–iron oxide shell nanoparticles coated with a multi-phosphonate brush co-polymer are shown to be small and effective magnetic nanoparticle imaging tracers.
Gabriela Jácome-Acatitla, Mayra Álvarez-Lemus, Rosendo López-González, Cinthia García-Mendoza, Andrés Sánchez-López, and Diego Hernández-Acosta
Elsevier BV
A.C. Reynosa-Martínez, G. Navarro Tovar, W.R. Gallegos, H. Rodríguez-Meléndez, R. Torres-Cadena, G. Mondragón-Solórzano, J. Barroso-Flores, M.A. Alvarez-Lemus, V. García Montalvo, and E. López-Honorato
Elsevier BV
R Trejo-Tzab, JA Aguilar-Jiménez, P Quintana-Owen, Alejandro Ávila-Ortega, MA Alvarez-Lemus, and RA Medina-Esquivel
SAGE Publications
The main motivation of this work is to deposit two different metals (gold and silver) on titanium oxide nanoparticles surface in a one-step simple and fast physical process by applying a nitrogen plasma as the main source of nitrogen atoms to obtain nanostructured N-TiO2 − X/Au/Ag materials. The obtained nanomaterials were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, diffuse reflectance spectroscopy, scanning electron microscopy–energy dispersive X-ray spectroscopy, and high-resolution transmission electron microscopy. Based on the characterization results, we found that gold and silver nanoparticles were uniformly loaded on the titanium oxide nanocomposite surface, showing a surface plasmon absorption band due to the loading of the metal nanoparticles over titania samples. The results of this work have shown that nitrogen plasma technique is a more feasible and simple alternative to obtain the N-TiO2 − X/Au/Ag nanocomposite. Moreover, this plasma technique could be used to impregnate with other kind of metals over the surface of diverse nanomaterials.
Daniela J Hernández‐Castillo, Mayra A Alvarez‐Lemus, Erick N de la Cruz‐Hernández, Rosendo López‐González, and Cinthia García Mendoza
Wiley
AbstractBACKGROUNDSelective etching of silica nanoparticles allows the formation of mesoporosity, increasing the loading capability of nanoparticles for further drug release applications. By coating such mesoporous silica nanoparticles with biocompatible pH‐sensitive polymers, the selectivity of drug delivery systems can be enhanced and adverse side effects can be minimized. So far, selectively etched silica has been scarcely explored for drug encapsulation.RESULTSSpherical particles with sizes ranging from 200 to 500 nm were obtained by the Stöber method. Selective etching was performed at two different aging times, leading to the formation of uniform pores with specific surface areas of 115 and 150 m2 g−1 for 0 and 14 h of aging respectively. X‐ray analysis demonstrated the formation of ordered materials, while the hydrodynamic sizes were around 300 nm. cis‐Diamminedichloroplatinum(II) was encapsulated in etched silica nanoparticles and coated with chitosan, and the drug was released at pH 5. In vitro evaluation of the nanoparticles was performed in U‐373 cells, reaching around 40% of cell death.CONCLUSIONSelective etching of nanoparticles allowed the obtaining of homogeneous coated hybrid nanoparticles and an efficient pH‐sensitive drug delivery hybrid system for the release of chemotherapeutic agent with enhanced activity against U‐373 human glioblastoma cells. © 2019 Society of Chemical Industry
M. C. Uribe López, M. A. Alvarez Lemus, M. C. Hidalgo, R. López González, P. Quintana Owen, S. Oros-Ruiz, S. A. Uribe López, and J. Acosta
Hindawi Limited
ZnO-ZrO2 nanocomposites using zinc (II) acetylacetonate and different ZnO contents (13, 25, 50, and 75% mol) were synthesized through sol-gel method. The synthesis process was strongly related to nanocomposite properties especially on their structural composition. The obtained ZnO-ZrO2 nanomaterials presented tetragonal crystalline structure for zirconia whereas hexagonal one was formed in ZnO. Raman spectroscopy and XRD patterns confirmed the formation of tetragonal zirconia whereas inhibition of monoclinic structure was observed. Addition of ZnO affected the pore size distribution of the composite, and the measured specific surface areas were from 10 m2/g (for pure ZnO) to 46 m2/g (pristine ZrO2). Eg values of ZrO2 were modified by ZnO addition, since calculated values using Kubelka-Munk’s function varied from 4.73 to 3.76 eV. The morphology and size of the nanomaterials investigated by electron microscopy showed formation of nanorods for ZnO with sizes ranging from 50 nm to 300 nm while zirconia was formed by smaller particles (less than 50 nm). The main advantage of using the nanocomposite for photocatalytic degradation of phenol was the mineralization degree, since 75ZnO-ZrO2 nanocomposite surpassed mineralization reached by pure ZnO and also inhibited formation of undesirable intermediates.
Cristina Trejo-Solís, Norma Serrano-Garcia, Ángel Escamilla-Ramírez, Rosa Castillo-Rodríguez, Dolores Jimenez-Farfan, Guadalupe Palencia, Minerva Calvillo, Mayra Alvarez-Lemus, Athenea Flores-Nájera, Arturo Cruz-Salgado,et al.
MDPI AG
Glioblastoma multiforme is the most malignant and aggressive type of brain tumor, with a mean life expectancy of less than 15 months. This is due in part to the high resistance to apoptosis and moderate resistant to autophagic cell death in glioblastoma cells, and to the poor therapeutic response to conventional therapies. Autophagic cell death represents an alternative mechanism to overcome the resistance of glioblastoma to pro-apoptosis-related therapies. Nevertheless, apoptosis induction plays a major conceptual role in several experimental studies to develop novel therapies against brain tumors. In this review, we outline the different components of the apoptotic and autophagic pathways and explore the mechanisms of resistance to these cell death pathways in glioblastoma cells. Finally, we discuss drugs with clinical and preclinical use that interfere with the mechanisms of survival, proliferation, angiogenesis, migration, invasion, and cell death of malignant cells, favoring the induction of apoptosis and autophagy, or the inhibition of the latter leading to cell death, as well as their therapeutic potential in glioma, and examine new perspectives in this promising research field.
Cristina Trejo-Solis, Mayra A. Alvarez-Lemus, Dolores Jiménez-Farfán, Isabel Anaya-Rubio, Rosendo López-González, Guadalupe Palencia, Dora M. Frías-Márquez, Gerardo González-García, Carmen Rubio-Osornio, Minerva Calvillo-Velasco,et al.
Wiley
Phenanthroline derivatives have been reported as potential bioactive compounds because of their ability to interact with DNA. To evaluate the antiproliferative effect of bis(acetylacetonate‐k2 O,O)(1,10‐phenanthroline‐k2 N,N)Zn(II) or Zn(acac)2(phen) complex, the compound was obtained in a simple manner and further characterized to determine crystal structure, thermal behavior, morphology, and spectroscopic properties. The structure of the complex was confirmed by X‐ray single structure as well as by 1H and 13C nuclear magnetic resonance (NMR) in dmso‐d6 (dimethyl sulfoxide) solution and in the solid state by 13C CP/MAS. Although preparation of this compound has been described previously, there are no reports on its biological activity; here, we assessed its antiproliferative effect on fibroblasts, A253, FaDu, Cal‐27, RH‐30, RD, U‐373, C6, A‐549, MDA‐MB‐231, and MCF‐7 cancer cell lines at different doses (50–100 and 150 μg/ml). The cell viability was determined by MTT assay and high activity was observed for the most of the cell lines, and TUNEL results showed the induction of apoptosis.
Mayra A Alvarez Lemus, Hugo Monroy, Tessy López, Erick N De la Cruz Hernández, and Rosendo López-González
Wiley
BACKGROUND
Surface composition of titanium dioxide (TiO2) nanoparticles strongly affects their biocompatibility and cytotoxicity. The appropriated functionalization of TiO2 nanoparticles leads to the improvement of these properties; while increasing biocompatibility allows the safety use of TiO2 nanoparticles, their cytotoxicity can be properly used in cancer therapy.
RESULTS
Amine functionalization of the sol–gel TiO2 nanoparticles was performed by in situ addition of -Gama- aminobutyric acid (GABA)-, and 1% mol of platinum (II) acetylacetonate. Fluoresceine isothiocyanate (FITC) was attached to the surface of the nanoparticles through amine-groups from GABA on the titanium dioxide surface. Nanoparticles obtained formed aggregates of around 100–300 nm. A strong and steady green-emission from labeled nanomaterials was observed. Transmission electron microscopy (TEM) showed that smaller particles (<100 nm) passed through the cellular membrane as they were observed within the cytoplasm and mitochondria. Activation of Caspase-3, a protein involved in apoptosis, was observed in treated cells, which agrees with terminal deoxynucleotidyl transferase dUTP nick end labeling assay results (TUNEL) where the highest DNA fragmentation was observed for Pt-TiO2-GABA nanomaterial.
CONCLUSIONS
TiO2 amino-functionalized nanoparticles were fluorescently labeled in a simple manner. The nanoparticles formed vesicles and activated a caspase-3 mediated mechanism to induce apoptosis. The addition of acetylacetone together with platinum promoted cell death. © 2016 Society of Chemical Industry
Getsemani Morales-Mendoza, Mayra Alvarez-Lemus, Rosendo López, Francisco Tzompantzi, Rajesh Adhikari, Soo Wohn Lee, Leticia M. Torres-Martínez, and Ricardo Gómez
Elsevier BV