Journal of the Mexican Chemical Society最新文献

{"title":"Aluminum Clusters (N=2-6) on CTF-0 Monolayer for Adsorption of Atrazine: Investigated by Density Functional Theory","authors":"Marisol Ibarra Rodríguez, M. Sánchez","doi":"10.29356/jmcs.v66i3.1760","DOIUrl":"https://doi.org/10.29356/jmcs.v66i3.1760","url":null,"abstract":"Abstract. We present a theoretical investigation of the structural characteristics and stabilities of neutral and positively charged aluminum clusters Aln n= 2-6 on covalent triazine frameworks (CTF-0). We found that clusters are adsorbed on the CTF-0 with adsorption energies of 26.32 – 91.53 kcal/mol. All calculations showed that the interaction between the aluminum cluster and CTF-0 is strong and prefers to adsorb in the central cavity of the monolayer with Al-C 2.03-2.92 Å and Al-N 1.89-2.12 Å bond formation. Next, we calculated the adsorption of an atrazine molecule on the [AlnCTF-0] n=2-6 systems. It is found that an atrazine molecule is physically adsorbed only on three systems, [AlnCTF-0] n=3-4,6 with adsorption energies in the range of 30.68 to 61.08 kcal/mol. The NBO analysis reveals that aluminum atoms accept electron density from nitrogen of atrazine molecule, but they also return electron density to the atrazine molecule. Although this result suggests that the [AlnCTF-0] n = 3-4,6 systems can be used as a promising candidate to remove the atrazine molecule.\u0000 \u0000Resumen. Presentamos una investigación teórica de las características estructurales y las estabilidades de los cúmulos de aluminio cargados positivamente y neutros Aln n = 2-6 en el fragmento de triazina covalente (CTF-0). Encontramos que los cúmulos se adsorben en el CTF-0 con energías de adsorción de 26.32 a 91.53 kcal/mol. Todos los cálculos mostraron que la interacción entre el cumulo de aluminio y CTF-0 es fuerte y prefiere adsorberse en la cavidad central de la monocapa con formación de enlaces Al-C 2.03-2.92 Å y Al-N 1.89-2.12 Å. Seguido, calculamos la adsorción de una molécula de atrazina en los sistemas [AlnCTF-0] n=2-6. Se encuentra que una molécula de atrazina se adsorbe físicamente sólo en tres sistemas, [AlnCTF-0] n=3-4,6 con energías de adsorción en el rango de 30.68 a 61.08 kcal/mol. El análisis NBO revela que los átomos de aluminio aceptan la densidad de electrones del nitrógeno de la molécula de atrazina, pero también devuelven densidad de electrones a la molécula de atrazina. Estos resultados sugieren que los sistemas [AlnCTF-0] n = 3-4,6 pueden usarse como candidatos prometedores para remover la molécula de atrazina.","PeriodicalId":17377,"journal":{"name":"Journal of the Mexican Chemical Society","volume":"11 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82009170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis, Characterization and Adsorptive Properties of Activated Carbon/KFeP2O7 Composite","authors":"E. Ordóñez Regil, Ana Paola Enríquez Sánchez, N. García González, María Guadalupe Almazán Torres","doi":"10.29356/jmcs.v66i3.1687","DOIUrl":"https://doi.org/10.29356/jmcs.v66i3.1687","url":null,"abstract":"Abstract. This work deals with the synthesis of nanoparticles of iron-potassium diphosphate, KFeP2O7, implanted on activated carbon produced from corncob debris. The chemical composition and structure of activated carbon/potassium-iron diphosphate (AC/KFP) composite was analyzed by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Complementary tests were conducted to determine surface characteristics such as surface area and point of zero charge (pHpzc). Further, the acid-base titration enabled to determine the surface sites density of AC/KFP composite. Adsorptive properties of AC/KFP composite vis à vis U(VI) was then tested using the batch method.\u0000 \u0000Resumen. Este trabajo presenta la síntesis de nanopartículas de difosfato de potasio-hierro, KFeP2O7, implantadas sobre carbón activado preparado a partir de restos de olote de maíz. La composición química y la estructura del compósito de carbono activado/difosfato de potasio-hierro (AC/KFP) se analizó mediante Difracción de Rayos X, Microscopía Electrónica de Barrido y Microscopía Electrónica de Transmisión. Se realizaron pruebas complementarias para determinar las características de la superficie, como el área de la superficie y el punto de carga cero (pHpzc). Además, la valoración ácido-base permitió determinar la densidad de sitios de superficie del compósito AC/KFP. Adicionalmente, las propiedades adsortivas del compósito AC/KFP frente a U (VI) fueron evaluadas utilizando el método de lotes.","PeriodicalId":17377,"journal":{"name":"Journal of the Mexican Chemical Society","volume":"143 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90408201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Study and Modeling of the Corrosion Inhibition of Mild Steel in 1M Hcl with Novel Friendly Butanolic Extract of Ephedra Major","authors":"Wafia Boukhedena, Samir Deghboudj, M. Benahmed, H. Laouer","doi":"10.29356/jmcs.v66i2.1630","DOIUrl":"https://doi.org/10.29356/jmcs.v66i2.1630","url":null,"abstract":"Abstract. A novel Butanolic extract of Ephedra major (denoted EBEM) was investigated as corrosion inhibitor for mild steel in 1 M hydrochloric acid solution. The investigation was carried out using weight loss, electrochemical impedance spectroscopy (EIS), Tafel polarization measurements, Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM) methods. The effect of temperature on the corrosion behavior of steel in HCl with the addition of the inhibitor was investigated in the temperature range 20-60°C. The inhibition efficiency was observed to increase with increasing concentration of the extract EBEM and deceased with increasing the temperature. Tafel curves have revealed that the EBEM possesses the indices of a mixed inhibitor. The adsorption of the inhibitor on the steel surface, follow Langmuir isotherm and its mode was found to be physical adsorption. Thermodynamic parameter (ΔG°ads) and activation parameters (Ea, ΔHa and ΔSa) were calculated to investigate the mechanism of inhibition. Obtained data were analyzed by suggesting two mathematical models based on linear and quadratic regressions, which takes into account the effect of concentration and temperature upon the inhibition efficiency. Experimental data were in good agreement with those predicted by both models.\u0000 \u0000Resumen. Se investigó un nuevo extracto butanólico de Ephedra major (denominado EBEM) como inhibidor de la corrosión del acero al carbono en una solución de ácido clorhídrico HCl 1 M. La investigación se llevó a cabo mediante métodos de pérdida de peso, espectroscopia de impedancia electroquímica (EIS), mediciones de polarización de Tafel, espectroscopia infrarroja por transformación de Fourier (FT-IR) y microscopía electrónica de barrido (SEM). Se investigó el efecto de la temperatura en el comportamiento de la corrosión del acero en HCl con la adición del inhibidor en el rango de temperaturas de 20-60°C. Se observó que la eficacia de la inhibición aumentó con el incremento de la concentración del extracto EBEM y disminuye con el aumento de la temperatura. Las curvas de Tafel han revelado que el EBEM posee los índices de un inhibidor mixto. La adsorción del inhibidor en la superficie del acero sigue la isoterma de Langmuir y su modo se encontró que era de adsorción física. Se calcularon los parámetros termodinámicos (ΔG°ads) y de activación (Ea, ΔHa y ΔSa) para investigar el mecanismo de inhibición. Los datos obtenidos se analizaron proponiendo dos modelos matemáticos basados en regresiones lineales y cuadráticas, que tienen en cuenta el efecto de la concentración y la temperatura sobre la eficacia de la inhibición. Los datos experimentales coincidieron con los predichos por ambos modelos.","PeriodicalId":17377,"journal":{"name":"Journal of the Mexican Chemical Society","volume":"21 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90501974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Selective Pb(II)-Imprinted Polymer for Solid Phase Extraction in the Trace Determination of Lead in Infant Formula by Capillary Electrophoresis","authors":"J. F. Flores-Aguilar, G. Islas, J. Rodríguez, M. Páez-Hernández, C. Galan-Vidal, I. Ibarra","doi":"10.29356/jmcs.v66i2.1694","DOIUrl":"https://doi.org/10.29356/jmcs.v66i2.1694","url":null,"abstract":"Abstract. A lead ion-imprinted polymer (IIP) based on methacrylic acid (MAA) and 4-vinylpyridine (4VP) as functional monomers has been synthesized by a radical precipitation method. The complex Pb-MAA-4VP was polymerized with ethylene glycol dimethacrylate as the cross-linker agent. The material was used in solid phase extraction (SPE) coupled with capillary electrophoresis (CE) for the determination of lead in infant formula samples. The physical-chemical properties of the IIP were characterized by scanning electron microscopy, IR spectroscopy, and Freundlich and Dubinin-Raduskevich models. The IIP selectivity was determined in presence of Ca(II), Mg(II), Cd(II), Cr(III) and Cu(II), which are present in the infant formula sample. The proposed methodology (SPE-CE) for the determination of lead has a limit of detection of 0.5 µg L-1 and a limit of quantification of 1.5 µg L-1, with an intra and inter-day repeatability of less than 5 % RSD in all cases. Four of twenty samples were positive for lead with concentrations ranging from 10 to 43 µg kg-1, and the results were compared with ETAAS. ANOVA demonstrated no significant difference between the results obtained by SPE-CE and ETAAS (α = 0.05 %).\u0000 \u0000Resumen. Se realizó la síntesis de un polímero impreso de iones (IIP) vía radicales libres para la extracción efectiva de plomo, empleando como monómeros funcionales ácido metacrilico (MAA) y 4-vinilpiridina (4VP). El complejo Pb-MAA-4VP fue polimerizado empleando al dimetacrilato de etilenglicol como agente entrecruzante. El polímero fue utilizado en un sistema de extracción en fase sólida (SPE) acoplado a electroforesis capilar (CE) en la determinación de plomo en muestras de fórmulas infantiles. El IIP óptimo fue caracterizado respecto a su morfología y propiedades fisicoquímicas mediante microscopia electrónica de barrido, espectroscopia IR e isotermas de adsorción (modelo Freundlich y Dubinin-Raduskevich).  La selectividad del IIP se estudió en presencia de iones metálicos contenidos en las fórmulas infantiles tales como: Ca(II), Mg(II), Cd(II), Cr(III) y Cu(II). La metodología propuesta en el presente trabajo (IIP-SPE-CE) mostró límites de detección de 0.5 µg L-1 y límites de cuantificación de 1.5 µg L-1, con una repetitividad y reproducibilidad adecuadas (< 5 % DER) en todos los casos. Cuatro de las veinte muestras analizadas dieron positivo a la presencia de plomo con concentraciones entre 10 a 43 µg L-1, dichos resultados fueron comparados con una metodología de referencia (ETAAS). El análisis de ANOVA demostró que no existe diferencia significativa entre los resultados obtenidos por IIP-SPE-CE y ETAAS (α=0.05 %).","PeriodicalId":17377,"journal":{"name":"Journal of the Mexican Chemical Society","volume":"74 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74829019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fabrication and Characterization of a Laboratory–Made New Coating Based on 1-Decyl-3-Methylimidazolium Tetrafluoroborate for SPME Fibers, an Exploration to its Application in Extractions by Direct-Immersion Mode","authors":"Omar J. Portillo-Castillo, R. Castro-Ríos, A. Chávez-Montes, A. Gónzalez-Horta, Norma Cavazos-Rocha, G. Granados-Guzmán, N. Waksman de Torres, Marsela Garza-Tapia","doi":"10.29356/jmcs.v66i2.1693","DOIUrl":"https://doi.org/10.29356/jmcs.v66i2.1693","url":null,"abstract":"Abstract. A novel coating for solid-phase microextraction (SPME) fibers was manufactured by using a mixture of 1-decyl-3methylimidazolium tetrafluoroborate ionic liquid and a commercial adhesive deposited on an etched stainless-steel support. The new coating was characterized by applying optical and electron microscopy, infrared spectroscopy and its extraction capacity was also evaluated. The extraction capacity was tested using as model analytes some pharmaceutical and personal care products (PPCPs) with different hydrophilicities. The potential use of the new fiber was evaluated through direct-immersion mode extractions and showed extraction capacity toward methylparaben, propylparaben, naproxen, diclofenac and benzophenone-3. Experimental design tools were used to study and optimize the variables that affect the extraction and desorption processes of the SPME by direct immersion. The analytical performance of proposed method was investigated under SPME procedure´s optimal conditions, coupled to a high-performance liquid chromatography-diode array detector (HPLC-DAD) method, which was developed and validated for analysis of the target PPCPs. The method of SPME by direct immersion was linear, precise and accurate. Detection and quantification limits of 0.023 to 0.093 μg mL-1 and 0.118 to 0.279 μg mL-1 were obtained, respectively. By the use of the developed method, tap water samples were analyzed and recoveries from 3.39 to 183.29 % were found. The new fiber presented an adequate stability and good extraction reproducibility (&lt;15 % RSD). As a final point, this device is of easy and quick preparation, inexpensive, and suitable for extraction of some PPCPs.\u0000 \u0000Resumen. Se fabricó un nuevo recubrimiento para fibras de microextracción en fase sólida (SPME) utilizando una mezcla del líquido iónico tetrafluoroborato de 1-decil-3metilimidazolio y un adhesivo comercial depositada sobre un soporte de acero inoxidable grabado. El nuevo recubrimiento se caracterizó mediante la aplicación de microscopía óptica y electrónica, espectroscopía de infrarrojo y también se evaluó su capacidad de extracción. La capacidad de extracción se probó utilizando como analitos modelo algunos productos farmacéuticos y de cuidado personal (PPCPs) con diferentes hidrofilicidades. El uso potencial de la nueva fibra se evaluó mediante extracciones en modo de inmersión directa y mostró capacidad de extracción hacia metilparabeno, propilparabeno, naproxeno, diclofenaco y benzofenona-3. Se utilizaron herramientas del diseño experimental para estudiar y optimizar las variables que afectan los procesos de extracción y desorción de la SPME por inmersión directa. El rendimiento analítico del método propuesto se investigó en las condiciones óptimas del procedimiento de SPME, acoplado a un método de cromatografía líquida de alto rendimiento con detector de arreglo de diodos (HPLC-DAD), que fue desarrollado y validado para el análisis de los PPCPs objetivo. El método de SPME por inmersión ","PeriodicalId":17377,"journal":{"name":"Journal of the Mexican Chemical Society","volume":"3 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81531290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-Relativistic Ro-Vibrational Energies of Chlorine Molecule for Molecular Attractive Potential Model","authors":"C. Onate, Ituen B. Okon, M. Onyeaju","doi":"10.29356/jmcs.v66i2.1712","DOIUrl":"https://doi.org/10.29356/jmcs.v66i2.1712","url":null,"abstract":"Abstract. We obtained the solutions of the radial Schrödinger equation with the modified molecular attractive potential model by employing the supersymmetric WKB method, and present the non-relativistic rotation-vibrational energy equation for diatomic molecules. Using the energy equation and the spectroscopic parameters of chlorine molecule, we computed the vibrational energy eigenvalues for various quantum states. The calculated results are found to be in agreement with the experimental values.\u0000 \u0000Resumen. Obtenemos las soluciones de la ecuación radial de Schrödinger con el modelo de potencial molecular atractivo modificado empleando el método WKB supersimétrico, y presentamos la ecuación para la energía rotacional-vibracional norelativista para moléculas diatómicas. Utilizando la ecuación para la energía y los parámetros espectroscópicos de la molécula de cloro, calculamos los valores propios de las energías vibracionales para varios estados cuánticos. Se encuentra que los resultados calculados están en acuerdo con los valores experimentales.","PeriodicalId":17377,"journal":{"name":"Journal of the Mexican Chemical Society","volume":"349 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77322766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of N-benzoyl Amino Esters and N-benzoyl Amino Acids and their Antifungal Activity","authors":"Yureli Chiguils-Pérez, Alejandro Israel Rodríguez-Hurtado, Lemuel Pérez-Picaso, Roxana Martínez-Pascual, M. D. L. A. Martínez-Rivera, E. Hernández-Núñez, Omar Viñas-Bravo, Sharon Rosete-Luna, Nelda X. Martinez-Galero","doi":"10.29356/jmcs.v66i1.1584","DOIUrl":"https://doi.org/10.29356/jmcs.v66i1.1584","url":null,"abstract":"Abstract. A series of N-benzoyl amino esters and N-benzoyl amino acids were synthesized from commercially-available amino acids (Val, Ile, Leu, Ala, Phe, Trp) and were evaluated for their antifungal activity against two filamentous fungi, A. fumigatus and F. temperatum. According to the in vitro assays, five compounds (5-7, 10, 13) exhibited relevant antifungal activity against F. temperatum and two compounds (5 and 7) showed remarkable activity against both fungi strains. Some structure-activity relationships were established regarding the side chain at Ca and the type of substituents on the aromatic ring in the benzoyl moiety. Docking calculations were performed in order to predict binding affinities between compounds prepared herein and fungal chitinase, a potential target against fungi; interactions involving the aromatic rings, the influence on the number of methyl substituents, and configurations on the a-carbon have been analyzed. \u0000  \u0000Resumen. Una serie de derivados N-benzoilamino ésteres y N-benzoilaminoácidos, sintetizados a partir de aminoácidos disponibles comercialmente (Val, Ile, Leu, Ala, Phe, Trp), se evaluaron como agentes antifúngicos frente a dos hongos filamentosos, A. fumigatus y F. temperatum. De acuerdo con los ensayos in vitro, cinco compuestos (5-7, 10, 13) exhibieron una actividad relevante contra F. temperatum y dos derivados (5 y 7) mostraron una actividad notable contra ambas cepas. Algunas relaciones de estructura actividad permitieron observar el efecto de la cadena lateral del aminoácido, y de los sustituyentes del grupo benzoílo, en la actividad biológica. Se realizaron cálculos de acoplamiento molecular con el propósito de predecir afinidades de enlace entre los compuestos sintetizados y la enzima quitinasa, considerada un blanco molecular potencial. Se analizaron las interacciones que involucran anillos aromáticos, la influencia de los sustituyentes metilo, así como la configuración del Ca.","PeriodicalId":17377,"journal":{"name":"Journal of the Mexican Chemical Society","volume":"190 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76950622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Polymers nature and Stirring Speeds on Physicochemical Properties and the Controlled Release of Allopurinol-loaded Microspheres","authors":"K. Badis, Haouaria Merine, Y. Ramli, O. Larbi, C. H. Memou","doi":"10.29356/jmcs.v66i1.1583","DOIUrl":"https://doi.org/10.29356/jmcs.v66i1.1583","url":null,"abstract":"Abstract. Allopurinol is an antigout drug therapy, commonly used in the treatment of chronic gout or hyperuricaemia associated with treatment of diuretic conditions. In the present study, new formulations based on Allopurinol, have been prepared with the microencapsulation by solvent evaporation process. Microspheres were prepared using pure Allopurinol and polymeric matrices (ethylcellulose EC, poly (ε-caprolactone) PCL, β-cyclodextrin CD and hydroxypropylmethylcellulose HPMC) at different compositions and stirring speeds to investigate the effect of these parameters on loading efficiency and drug release kinetics. The formulations produced were characterized by various methods : Fourier transforms infrared spectroscopy (FTIR), X-ray powder diffractometry, optical microscopy, surface morphology by scanning electron microscopy (SEM) and drug loading, as well as in vitro release studies in the simulated stomach tract. Depending on the stirring speed and the composition of the microparticles, the active ingredient loading is in a range from 10.46 ± 1.45 to 46.40 ± 0.5%. The microspheres are spherical and the mean Sauter diameter (d32) of the microparticles obtained is smaller and is in the range of 47.71 to 151.01 µm. Different release profiles were obtained and show that the release rate is strongly influenced by the characteristics of the microparticles ; namely, the stirring rates and the composition of the microparticles. The release mechanism was identified by modelling using Higuchi and Korsmeyer-Peppas models. \u0000  \u0000Resumen. Alopurinol es una droga terapéutica para tratar la gota, y se utiliza en el tratamiento de gota crónica o hiperuricemia asociada con el tratamiento de condiciones diuréticas. En este estudio, nuevas formulaciones basadas en Alopurinol se prepararon mediante microencapsulación por el proceso de evaporación de disolvente. Microesferas se prepararon usando Alopurinol puro y diferentes matrices poliméricas (etil-celulosa EC, poli(-caprolactona) PCL, β-cyclodextrina CD e hidroxipropil-metil-celulose HPMC) en diferentes composiciones y velocidades de agitación, para investigar el efecto de estos parámetros en la eficiencia de carga y en la cinética de liberación del fármaco. Las formulaciones obtenidas fueron caracterizadas por diferentes técnicas : Espectroscopía infrarroja de transformadas de Fourier (FTIR), difractometría de rayos X de polvos, microscopía óptica, morfología de superficies mediante microscopía electrónica de barrido electrónico, y la eficiencia de carga del fármaco, así como estudios de liberación in vitro en tracto estomacal simulado. Dependiendo de la velocidad de agitación y la composición de las micropartículas, la carga del ingrediente activo se encuentra en el rango de 10.46 ± 1.45 a 46.40 ± 0.5%. Las microesferas son esféricas y el diámetro medio de Sauter (d32) de las micropartículas obtenidas es menor, y se encuentra en el rango de 47.71 a 151.01 µm. Se obtuvieron diferentes perfiles de liberación y ","PeriodicalId":17377,"journal":{"name":"Journal of the Mexican Chemical Society","volume":"2 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89872042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of thermochemical Features of Gamma Irradiated Tryptophan Stereoisomers","authors":"A. Neacsu, D. Gheorghe, Victorita Tecuceanu, S. Perişanu","doi":"10.29356/jmcs.v66i1.1627","DOIUrl":"https://doi.org/10.29356/jmcs.v66i1.1627","url":null,"abstract":"Abstract. In this work, the use of differential scanning calorimetry (DSC) is demonstrated as a powerful technique that can provide accurate thermodynamic property values of nutritional supplements such as tryptophan. Nutritional supplements require a decontamination procedure and irradiation appears as a promising technique for this purpose. The valuable properties of tryptophan for food and pharmaceutical industry as dietary supplement have led to increasing interest in its technological behaviour. L-, D- isomers and DL-racemic mixture of tryptophan irradiated and non-irradiated were studied by DSC. Irradiation was performed at room temperature with gamma radiations using a 137Cs source, the irradiation dose range was between 0.6- 10 kGy. Two steps decomposition pattern for both irradiated and non-irradiated samples up to 350 oC was found. Fourier transform infrared spectroscopic studies were performed. The obtained results indicate that the irradiation process does not inhibit the thermal properties of tryptophan when irradiated up to 10 kGy. The HPLC method was employed to evidence the degradation of the irradiated material. \u0000  \u0000Resumen. En este trabajo, se demuestra el uso de calorimetría diferencial de barrido (DSC) como una técnica poderosa que puede proporcionar valores precisos de propiedades termodinámicas de suplementos nutricionales como el triptófano. Los suplementos nutricionales requieren un procedimiento de descontaminación y la irradiación aparece como una técnica prometedora para este propósito. Las valiosas propiedades del triptófano para la industria alimentaria y farmacéutica como suplemento dietético han provocado un creciente interés por su comportamiento tecnológico. Los isómeros L-, D- y la mezcla racémica DL- de triptófano irradiado y no irradiado fueron estudiados por DSC. La irradiación se realizó a temperatura ambiente con radiaciones gamma utilizando una fuente de 137Cs, el rango de dosis de irradiación estuvo entre 0.6 - 10 kGy. Se encontró un patrón de descomposición de dos pasos para muestras irradiadas y no irradiadas hasta 350 ºC. Se realizaron estudios espectroscópicos de infrarrojos por la transformada de Fourier. Los resultados obtenidos indican que el proceso de irradiación no inhibe las propiedades térmicas del triptófano cuando se irradia hasta 10 kGy. Se empleó el método HPLC para evidenciar la degradación del material irradiado.","PeriodicalId":17377,"journal":{"name":"Journal of the Mexican Chemical Society","volume":"47 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91333813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Natural Products and Pharmacological Biodiversity of Brown Algae from the Genus Dictyopteris","authors":"Mohammed I. Rushdi, Iman A. M. Abdel- Rahman, H. Saber, Eman Zekry Attia, Usama Ramadan Abdelmohsen","doi":"10.29356/jmcs.v66i1.1639","DOIUrl":"https://doi.org/10.29356/jmcs.v66i1.1639","url":null,"abstract":"Abstract. Genus Dictyopteris is an important genus among marine seaweeds and is excessively distributed and known by its ocean smell due to its secondary metabolites including C11-hydrocarbons and sulfur compounds. This chemical feature is responsible for its interesting biological properties. This review detected the literature from 1959 to 2021 on the genus Dictyopteris and revealed the secondary metabolites, together with biological activities of the genus Dictyopteris to create the base for additional studies on its clinical and pharmaceutical applications. \u0000  \u0000Resumen. El género Dictyopteris es un género importante entre las algas marinas y está excesivamente distribuido y conocido por su olor a océano debido a sus metabolitos secundarios que incluyen hidrocarburos C11 y compuestos de azufre. Esta característica química es responsable de sus interesantes propiedades biológicas. Esta revisión detectó la literatura de 1959 a 2021 sobre el género Dictyopteris y reveló los metabolitos secundarios, junto con las actividades biológicas del género Dictyopteris, para crear la base para estudios adicionales sobre sus aplicaciones clínicas y farmacéuticas.","PeriodicalId":17377,"journal":{"name":"Journal of the Mexican Chemical Society","volume":"20 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2021-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82915090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}