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In the last decade, the green synthesis of nanoparticles has had a prominent role in scientific research for industrial and biomedical applications. In this current study, silver nitrate (AgNO3) was reduced and stabilized with an aqueous extract of Thelypteris glandulosolanosa (Raqui-raqui), forming silver nanoparticles (AgNPs-RR). UV-vis spectrophotometry, dynamic light scattering (DLS), and scanning transmission electron microscopy (STEM) were utilized to analyze the structures of AgNPs-RR. The results from this analysis showed a characteristic peak at 420 nm and a mean hydrodynamic size equal to 39.16 nm, while the STEM revealed a size distribution of 6.64–51.00 nm with an average diameter of 31.45 nm. Cellular cytotoxicity assays using MCF-7 (ATCC® HTB-22™, mammary gland breast), A549 (ATCC® CCL-185, lung epithelial carcinoma), and L929 (ATCC® CCL-1, subcutaneous connective tissue of Mus musculus) demonstrated over 42.70% of MCF-7, 59.24% of A549, and 8.80% of L929 cells had cell death after 48 h showing that this nanoparticle is more selective to disrupt neoplastic than non-cancerous cells and may be further developed into an effective strategy for breast and lung cancer treatment. These results demonstrate that the nanoparticle surfaces developed are complex, have lower contact angles, and have excellent scratch and wear resistance.

Cotton is the most widely used natural fiber for textiles; however, the capacity of cotton fibers to absorb large amounts of moisture, retain oxygen, and have a high specific surface area makes them more prone to microbial contamination, becoming an appropriate medium for the growth of bacteria and fungi. In recent years, the incorporation of silver nanoparticles in textile products has been widely used due to their broad-spectrum antibacterial activity and low toxicity towards mammalian cells. The aim of the current study is to continue the assessment of our developed nanocomposite and evaluate the antibacterial and antifungal activity of the nanocomposite based on silver nanoparticles and carboxymethyl chitosan (AgNPs-CMC) against Escherichia coli, Staphylococcus aureus, and Candida albicans, evaluated by the well diffusion method. The antibacterial activity against E. coli and S. aureus was also evaluated by the qualitative method of inhibition zone and the quantitative method of colony counting. Likewise, the antifungal activity of the functionalized fabric against Candida albicans and Aspergillus niger was determined by the inhibition zone method and the antifungal activity method GBT 24346-2009, respectively. The functionalized fabric showed 100% antibacterial activity against E. coli and S. aureus and good antifungal activity against C. albicans and A. niger. Our results indicate that the functionalized fabric could be used in garments for hospital use to reduce nosocomial infections.

En la presente investigación presentamos un composito de polisiloxano funcionalizado con nanopartículas de plata (NPs-Ag). Se sintetizó NPs-Ag, por reducción de una solución de nitrato de plata (AgNO3) con borohidruro de sodio (NaBH4), las NPs-Ag se caracterizaron por el método espectrofotométrico UV-visible, encontrando que entre 400 – 410 nm se formó el típico pico de las NPs-Ag por la resonancia de plasmón superficial. En el análisis por Dispersión de Luz Dinámica (DLS) de las NPs-Ag se encontró una distribución polidispersa con dos poblaciones de 59,78 nm en un 70 % y de 4,33 nm en un 30%. Seguidamente, se sintetizó el gel de polisiloxano por hidrolización de clorosilano, usando como disolvente éter dietílico, el polisiloxano obtenido se caracterizó por espectrofotometría infrarroja con transformada de Fourier (FTIR). En el espectro se observan picos en la región de 1258,88 cm-1 correspondientes al metilo, entre 1000 - 1100 cm-1 un pico correspondiente al enlace Si- O-Si y una banda a 792,10 cm-1 característica de los siloxanos, confirmándose la presencia del polisiloxano. Se funcionalizó el gel de polisiloxano (PS) con NPs-Ag, obteniéndose un gel de color amarillo lechoso, debido a la absorción por resonancia de los plasmones superficiales. El análisis por DLS del gel de PS-NPs-Ag, mostró una distribución monodispersa con un tamaño promedio de 158,7 nm en un 100 %, debido a que el gel incluye en su estructura las NPs-Ag. Se caracterizó el gel de PS-NPs-Ag por FTIR observándose un pico entre 1000 y 1100 cm-1 correspondiente al Si-O-Si y una banda a 803,33 cm-1 propia de los siloxanos; asimismo, se observa una banda de absorción a 3384 cm-1 correspondiente a las NPs-Ag. En el análisis termogravimétrico (TGA) del gel de PS-NPs-Ag se muestra que a la temperatura de 374,96°C alcanza el punto de fusión, característico de un polisiloxano y a 630,22 °C la muestra se descompone. Mediante Espectrometría de Masas con Plasma Acoplado Inductivamente (ICP-MS) se encontró una concentración de plata de 5,2 ppm. Por SEM-EDX se observa la morfología típica del gel de PS-NPs-Ag, además se observa una señal que corresponde a la presencia de plata.

Cotton is the most widely used natural fiber for textiles but its innate capacity to absorb moisture, retain oxygen, and high specific surface area make it more prone to microbial contamination, becoming an appropriate medium for the growth of bacteria and fungi. In recent years, the incorporation of silver nanoparticles in textile products has been widely used due to their broad-spectrum antibacterial activity and low toxicity towards mammalian cells. The aim of the current study is to synthesize and characterize a nanocomposite based on silver nanoparticles and carboxymethyl chitosan (AgNPs-CMC), which was utilized to provide a functional finish to cotton fabric. The scanning electron microscope (SEM) to produce a scanning transmission electron microscope (STEM) image showed that the nanocomposite presents AgNPs with a 5–20 nm size. The X-ray diffraction (XRD) analysis confirmed the presence of silver nanoparticles. The concentration of silver in the functionalized fabric was evaluated by inductively coupled plasma optical emission spectrometry (ICP-OES), which reported an average concentration of 13.5 mg of silver per kg of functionalized fabric. SEM showed that silver nanoparticles present a uniform distribution on the surface of the functionalized cotton fabric fibers. On the other hand, by infrared spectroscopy, it was observed that the functionalized fabric variation (compared to control) had a displaced peak of intensity at 1594.32 cm−1, corresponding to carboxylate anions. Similarly, Raman spectroscopy showed an intense peak at 1592.84 cm−1, which corresponds to the primary amino group of carboxymethyl chitosan, and a peak at 1371.5 cm−1 corresponding to the carboxylic anions. Finally, the physical and mechanical tests of tensile strength and color index of the functional fabric reported that it was no different (p ˃ 0.05) than the control fabric. Our results demonstrate that we have obtained an improved functionalized cotton fabric using green chemistry that does not alter intrinsic properties of the fabric and has the potential to be utilized in the manufacturing of hospital garments.

El deterioro de las construcciones hechas con ignimbrita en el centro histórico de Arequipa, es un problema causado por el intemperismo, emisión de contaminantes industriales y biológicos, afectando su preservación. Se evaluó aplicar a la ignimbrita, polisiloxano funcionalizado con nanopartículas de plata (PXS-AgNPs), como recubrimiento para disminuir su porosidad, evitar su degradación y darle un efecto protector a su superficie.Las nanopartículas de plata (AgNPs) se sintetizaron, por reducción de nitrato de plata (AgNO3) con borohidruro de sodio (NaBH4), el polisiloxano se sintetizó por hidrólisis del clorosilano en agua y éter dietílico; que fue funcionalizado con AgNPs, mezclando soluciones acuosas de PXS y de AgNPs, obteniéndose un gel de color amarillo lechoso. Se aplicó PXSAgNPs a la superficie de la ignimbrita y se realizaron pruebas de adsorción con solución de azul de metileno 1ppm, que se contrastó con ignimbrita sin PXS-AgNPs. Encontrando en la ignimbrita con PXS-AgNPs un porcentaje de recubrimiento del 85,98 % y en la ignimbritasin PXS-AgNPs un porcentaje de recubrimiento del 61,04%, existiendo una diferencia de 36,65% de adsorción, demostrándose que con el PXS-AgNPs se mejora la protección de la ignimbrita. Se caracterizó la ignimbrita recubierta con PXS-AgNPs, por SEM EDX observando una estructura con cristalizaciones y una tenue capa cubriéndolas del PXS-AgNPs; por EDX se observa una señal por la presencia de plata; por FT/IR bandas a 981 cm-1 y 1243 cm-1 del siloxano; en el análisis por TGA una inflexión a 362.65ºC del punto de fusión del PXS, a 630,22°C por la descomposición del PXS, lo que indica que tiene resistencia térmica; en el análisis por ICP-masa se encontró 0.48 mg/K de Ag por su presencia en el PXS-AgNPs.En cuanto a la actividad antimicrobial del PXS-AgNPs, se encontró la disminución de mesófilos totales de 3950 UFC/g en la ignimbrita sin PXS-AgNPs a 125 UFC/g en la ignimbrita con PXS-AgNPs; los hongos disminuyeron de 4 UFC/g en la ignimbrita sin PXSAgNPs a 1 UFC/g en la ignimbrita con PXS-AgNPs, lo que demuestra la efectividad del PXS-AgNPs ante la actividad microbiana.Todas las pruebas realizadas demuestran la efectividad del PXS-AgNPs como recubrimiento, tanto en el aspecto fisicoquímico como en la actividad microbiana, mejorando la protección de la ignimbrita.

Se realizó la síntesis del nanocomposito, nanopartículas de plata y O-carboximetil quitosano (NPsAg-CMQ), por el método de reducción química, utilizando el O-carboximetilquitosano 0,01 % y AgNO 1 mM en una proporción de 3:2, con un tiempo de reacción de 30 minutos a temperatura ambiente y pH neutro. El nanocomposito obtenido a partir del complejo [Ag(NH ) ]+ fue sintetizado bajo las mismas condiciones que el AgNO , pero a un pH básico. Por espectrofotometría UV-VIS, se verificó la formación del plasmón de nanopartículas de plata a 410 nm, para ambas fuentes de plata. Los resultados por Dispersión Dinámica de Luz (DLS) para el AgNO , muestra una distribución monodispersa del nanocomposito con un tamaño hidrodinámico promedio de 166,7 nm. En el caso del diaminplata [Ag(NH ) ]+ un 83,9 % tuvieron un tamaño promedio de 54,42 nm. y 15,2 % de 4,48 nm. Mediciones de Espectroscopia Infrarroja con Transformada de Fourier (FT-IR) muestra la inhibición de las bandas espectrales a 879 y 723 cm-1 indicando la presencia de las NPsAg en el nanocomposito NPsAg-CMQ. Los resultados de Microscopía Electrónica de Barrido (SEM-STEM) evidenciaron que las nanopartículas de plata en el nanocomposito fueron de forma esférica y de un tamaño de 5 a 20 nm. The synthesis of the nanocomposite based on silver nanoparticles and O-carboxymethyl chitosan (NPsAg-CMQ), by the chemical reduction method, using the O-carboxymethylchitosan 0.01% and AgNO 1 mM in a ratio of 3: 2, with a time of 30 minute reaction, at room temperature and neutral pH. The nanocomposite obtained from the complex [Ag(NH ) ]+ was synthesized under the same conditions as AgNO but at a basic pH. Using UV-VIS spectrophotometry, the plasmon formation of silver nanoparticles at 410nm was verified for both silver sources. The results by Dynamic Light Dispersion (DLS) for AgNO , shows a monodisperse distribution of the nanocomposite with an average hydrodynamic size of 166.7 nm. In the case of the diamine silver [Ag(NH ) ] + 83.9% had an average size of 54.42 nm. and 15.2% of 4.48 nm. Infrared Spectroscopy Measurements with Fourier Transform (FT-IR) shows the inhibition of the spectral bands at 879 and 723 cm-1 indicating the presence of NPsAg in the nanocomposite NPsAg-CMQ. The results of scanning electron microscopy (SEM-STEM) showed that the silver nanoparticles in the nanocomposite were spherical in shape and of a size of 5 to 20 nm.

In the present investigation, an ethanolic fraction (EF) of Lepechinia meyenii (salvia) was prepared and fractionated by gradient column chromatography, and the main secondary metabolites present in the EF were identified by HPLC-MS. Silver nanoparticles (AgNPs) were synthesized and conjugated with the EF of Lepechinia meyenii (salvia). The AgNPs synthesis was optimized using Plackett-Burman design and response surface methodology (RSM), considering the following independent variables: stirring speed, synthesis pH, synthesis time, synthesis temperature and EF volume. The AgNPs synthesized under the optimized conditions were characterized by UV visible spectroscopy (UV-VIS), Fourier Transform Infrared Spectroscopy (FT-IR), Dynamic Light Scattering (DLS) and Scanning Transmission Electron Microscopy (STEM). The antibacterial activity of the AgNPs against Staphylococcus aureus (ATCC® 25923) was evaluated. The following flavonoids were identified: rosmarinic acid, diosmin and hesperetin-7-O-rutinoside. The optimized conditions for the synthesis of nanoparticles were pH 9.45, temperature 49.8 °C, volume of ethanolic fraction 152.6 µL and a reaction time of 213.2 min. The obtained AgNPs exhibited an average size of 43.71 nm and a resonance plasmon of 410–420 nm. Using FT-IR spectroscopy, the disappearance of the peaks between 626.50 and 1379.54 cm−1 was evident with the AgNPs, which would indicate the participation of these functional groups in the synthesis and protection of the nanoparticles. A hydrodynamic size of 47.6 nm was obtained by DLS, while a size of 40–60 nm was determined by STEM. The synthesized AgNPs conjugated with the EF showed a higher antibacterial activity than the EF alone. These results demonstrate that the AgNPs synthesized under optimized conditions conjugated with the EF of the Lepechinia meyenii (salvia) presented an increased antibacterial activity.

The fractionation of Crotalus durissus collilineatus whole venom through an HPLC chromatographic method enabled the purification of a new V-1 neurotoxin. Inter-CRO (V-1) presents similarity in its primary structure to crotoxin B (CB), suggesting another isoform of this toxin. The aim of this study was to compare V-1 to the crotoxin complex (CA/CB) and CB to elucidate aspects related to its functionality. The homogeneity of the purified protein was confirmed with a molecular mass of 1425.45 Da, further verified by mass spectrometry. The sequence of the protein showed high similarity to other viperid snake venom PLA2 proteins. The results of this study report that V-1 is an uncharacterized novel toxin with different biological activities from CB. V-1 maintained catalytic activity but presented neurotoxic activity as observed by the 2.5-fold increase in twitch tension record compared to control values on isolated muscle cells.

El O-carboximetilquitosano (O-CMQ) fue derivatizado a partir del copolímero quitosano por el método de alquilación directa. Este método implicó la reacción del quitosano con ácido monocloroacético previa alcalinización. El producto derivatizado mostró solubilidad en un rango de pH de 1-13 y a pH=5 exhibió baja solubilidad. El grado de sustitución (GS) fue de 0,92 mol/mol, determinado por titulación conductimétrica. Los resultados de Espectroscopia Infrarroja con Transformada de Fourier (FT-IR) permitieron identificar una banda de absorción de intensidad fuerte a 1585cm-1, correspondiente al estiramiento del C=O, lo que indica la presencia de un anión carboxílico (-COO- ), que es característico del O-carboximetilquitosano. Mediante Espectroscopia de Resonancia Magnética Nuclear de Hidrógeno y del carbono ( 1 H NMR, 13C NMR) se mostró que la sustitución se llevó a cabo en el carbono 3 y 6 del quitosano. El O-CMQ a concentración de 50mg/mL, incrementó la supervivencia celular en un 8 % frente a la toxicidad del Pb (II) a una concentración de 41,44mg/mL. The O-carboxymethylchitosan (O-CMQ) was derivatized from the chitosan copolymer by the direct alkylation method. This method involved the reaction of the chitosan with monochloroacetic acid after alkalinization. The derivatized product showed solubilityin a pH range of 1-13 and low solubility at pH = 5. The degree of substitution (GS) was 0,92, determined by conductometric titration. The results of Fourier Transform Infrared Spectroscopy (FT-IR) allowed us to identify a strong intensity absorption band at 1585cm-1, corresponding to the stretching of C = O, which indicates the presence of a carboxylic anion (-COO- ) that is characteristic of O-carboxymethylchitosan (O-CMQ). Using the Nuclear Magnetic Resonance spectroscopy of proton and carbon-13 (1 H NMR, 13C NMR) showed that the substitution was carried out on carbon 3 and 6 of chitosan. The derivatized O-CMQ at concentration of 50mg / mL, increased cell survival by 8 % compared to the toxicity of Pb (II) at concentration of 41,44 mg/mL.

Four novel complexes of cadmium(II) with alkyl/aryl-substituted malonate ligands of formulae {[Cd(Memal)(H2O)]6·0.5H2O}n (1), [Cd(Etmal)(H2O)]n (2), [Cd(Butmal)(H2O)]n (3) and [Cd(Bzmal)(H2O)]n (4), (Memal = methylmalonate, Etmal = ethylmalonate, Butmal = butylmalonate and Bzmal = benzylmalonate) have been prepared and characterized by single crystal X-ray analysis. Their luminescence, UV-Vis absorption properties and thermal behaviour were also investigated. Complex 1 is a three-dimensional compound where each metal centre is connected to four other ones leading to a sodalite network with the point symbol {42·64}. Each cadmium(II) ion in 1 is seven-coordinate with a water molecule and six oxygen atoms from three Memal ligands building a somewhat distorted pentagonal bipyramidal surrounding. The Memal ligand in 1 adopts a μ3–κO:κ2O′:κ2O′′:κO′′′ coordination mode. 2–4 are isomorphous compounds with a two-dimensional structure where centrosymmetric double oxo(carboxylate-substituted malonate)-bridged dicadmium(II) units are linked to four other dinuclear entities through anti–anti and anti–syn carboxylate bridges to form a Shubnikov tetragonal layered [4462]-sql net. Each cadmium(II) ion in 2–4 is six-coordinate in a distorted octahedral environment with four carboxylate-oxygen atoms building the basal plane and a water molecule plus another carboxylate-oxygen atom in the axial positions. The substituted malonate ligands in 2–4 exhibit the μ4–κO:κ2O′:κ2O′′:κO′′′ coordination mode. The tests of the emission spectra of 1–4 show that the length of the side chain influences the photoluminescence properties of the complexes. Finally, the decays of the luminescence of 1–4 and the respective free substituted malonic acids reveal that the same value of the average life time is observed for 1 (H2Memal), whereas in the case of 2–4, they are greater than that of 1 and those of their corresponding acids. The longer decay rates in 2–4 are consistent with the lack of water molecules in the environment of the cadmium(II) ion in these complexes, indicating that the sheet-like structure of 2–4 provides a chemical surrounding with less non-radiative relaxation processes.

Se formuló un filtro con un nanocompósito de arcilla-carboximetilquitosano-nanopartículas de plata, que se usó para eliminar bacterias y aniones en aguas de consumo humano. Las nanopartículas de plata se obtuvieron por reducción del nitrato de plata 1mM, con carboximetilquitosano al 0,01 % y borohidruro de sodio 2mM como iniciador de la reducción. Posteriormente, se obtuvo los filtros como recipientes con arcilla y aserrín de madera como formador de poros, en la proporción de 2:1; se moldeó, secó y sinterizó a 800°C por tres horas. Seguidamente, los filtros se impregnaron con la dispersión coloidal de carboximetilquitosano-nanopartículas de plata, por inmersión durante 12 horas. Se definieron cuatro puntos de muestreo del agua: Huacapuy, La Punta, Plaza de Quilca, Caleta de Quilca. Al evaluar la capacidad filtrante de los filtros, se encontró que se remueven: conductividad 84,03 % en La Plaza de Quilca, sulfatos 85,48 % en La Plaza de Quilca; cloruros 93,93 % en La Plaza de Quilca. Por otro lado, las bacterias coliformes fecales y coliformes totales se removieron en un 100 % en La Punta y en la Plaza de Quilca. No se encontraron bacterias coliformes en Huacapuy ni en la Caleta de Quilca. Por lo que se puede confirmar que los resultados tienen un porcentaje de remoción significativo en la eliminación de aniones, en cuanto a bacterias coliformes totales y coliformes fecales se removieron en su totalidad. A filter made of a nanocomposite of clay – carboximethylchitosan – silver nanoparticles was created to eliminate bacteria and anions in water for human consumption. The silver nanoparticles were obtained by reduction of silver nitrate 1mM, with carboximethyl chitosan at 0.01% and sodium borohydrido 2mM as starter of the reduction. Then the clay filters were made with wood sawdust as the pore maker in a 2:1 proportion; it was molded, dried and sinterized at 800°C for 3 hours. Quickly the filters were impregnated with the colloidal dispersion of carboximethyl chitosan – silver nanoparticles by immersion for 12 hours. Four water sampling points were defined: Huacapuy, La Punta, Plaza de Quilca, Caleta de Quilca. When evaluating the filtering capacity of the filters, it was found that the following were removed: conductivity 84.03% in La Plaza de Quilca, sulfates 85.48% in La Plaza de Quilca; 93.93% chlorides in La Plaza de Quilca. On the other hand, fecal coliform bacteria and total coliforms were removed 100% at La Punta and Plaza de Quilca. No coliform bacteria were found in Huacapuy or in the Caleta de Quilca. So it can be confirmed that the results have a significant removal percentage in the elimination of anions, in terms of total coliform bacteria and fecal coliforms were removed in its entirety

Objetivos. Evaluar el efecto antiinflamatorio de la fracción flavonoide de Lepechinia meyenii (Walp.) Epling sobre leucocitos de pacientes con artritis reumatoide (AR). Materiales y métodos. Se recolectaron plantas de la especie Lepechinia meyenii (Walp.) Epling extrayendo diferentes fracciones flavonoides por cromatografía de columna y de capa fina. Se evaluó la producción de anión superóxido mediante la técnica de ensayo reducción nitroblue tetrazolium, en neutrófilos obtenidos de sangre de pacientes con AR, separados en tres grupos: control negativo, que consistió de neutrófilos (5x10(5) células), control positivo, formado por neutrófilos activados con PMA (phorbol myristate acetate) (150 ng/mL) y los tratamientos, formados por neutrófilos activados y tratados con diferentes concentraciones de la fracción flavonoide LM8 (60, 120 y 180 ug/mL). La expresión de genes proinflamatorios se estudió por RTqPCR, en leucocitos mononucleares obtenidos de pacientes con AR separados en tres grupos: control negativo, que consistió de leucocitos mononucleares (5x10(5)células), control positivo formado por leucocitos mononucleares activados con fitohemaglutinina (PHA) (150 ug/mL) y el tratamiento formado por leucocitos mononucleares activados y tratados con la fracción flavonoide LM8 (120 ug/mL). Resultados. Se purificaron varias fracciones flavonoides, resultando la fracción LM8 con el mejor efecto inmunomodulador. Dicha fracción disminuyó la producción de anión superóxido en una manera dependiente de la concentración. Por otro lado, disminuyó la expresión de TNFα, IL8 e IL17 en leucocitos mononucleares Conclusiones. Estos resultados son alentadores respecto al efecto inmunomodulador de esta planta medicinal peruana y justifican continuar su estudio para una posible aplicación clínica. Objectives. to assess the anti-inflammatory effect of the flavonoid fraction of Lepechinia meyenii (Walp.) Epling on leukocytes of patients with rheumatoid arthritis (RA). Materials and Methods. Plants of the species Lepechinia meyenii (Walp.) Epling were collected and then different flavonoid fractions were extracted by column and thin layer chromatography. The superoxide anion production was evaluated by means of the reduction of nitroblue tetrazolium assay technique in neutrophils obtained from the blood of patients with RA, divided into three groups: negative control, which consisted of neutrophils (5x10(5) cells); positive control, made up of PMA (phorbol myristate acetate)-activated neutrophils (150 ng/mL), and the treatments, comprised of neutrophils activated and treated with different concentrations of the flavonoid fraction LM8 (60, 120, and 180 ug/mL). The expression of pro-inflammatory genes was studied by RTqPCR in mononuclear leukocytes obtained from patients with RA, divided into three groups: negative control, which consisted of mononuclear leukocytes (5x10(5) cells); positive control, made up of phytohaemagglutinin (PHA) (150 ug/ml)-activated mononuclear leukocytes, and the treatment, comprised of mononuclear leukocytes activated and treated with the flavonoid fraction LM8 (120 ug/mL). Results. Several flavonoid fractions were purified, with fraction LM8 showing the best immunomodulating effect. Said fraction diminished the superoxide anion production dependent on concentration. On the other hand, it diminished the expression of TNFα, IL8, and IL17 in mononuclear leukocytes. Conclusions. These results are encouraging in terms of the immunomodulating effect of this Peruvian medicinal plant and justify the continuation of their study for a potential clinical application.