“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 ...

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 con...

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 ...

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...

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 / ...

Introducción: La hidroxiapatita (HAp) es un biocerámico que se encuentra como principal componente inorgánico de los dientes y huesos, cuyo estudio detallado de sus características es de suma importancia por sus aplicaciones como implante, refuerzo, filtro, etc. El método convencional para sintetizar HAp es el método sol-gel, sin embargo, metodologías alternativas como la mecano-síntesis se perfilan como formas emergentes de producción en masa ya que utiliza compuestos basados en biodesechos y a la vez brindan valor agregado al producto final. Metodología: En el presente trabajo se preparó HAp mediante dos métodos: químico (sol-gel) y físico (mecano-síntesis), utilizando como fuente de iones de Ca2+ al nitrato de calcio y la cáscara de huevo, respectivamente. Se evaluaron las características estructurales, químicas, morfológicas y mecánicas de ambas muestras mediante ...

In the present investigation we present a polysiloxane composite functionalized with silver nanoparticles (NPs-Ag). NPs-Ag was synthesized, by reduction of a silver nitrate solution (AgNO3) with sodium borohydride (NaBH4), the NPs-Ag were characterized by the UVvisible spectrophotometric method, finding that between 400 - 410 nm the typical peak of NPs-Ag by surface plasmon resonance. In the Dynamic Light Scattering (DLS) analysis of the NPs-Ag, a polydisperse distribution was found with two populations of 59.78 nm in 70% and 4.33 nm in 30%. Subsequently, the polysiloxane gel was synthesized by hydrolyzing chlorosilane, using diethyl ether as the solvent, the obtained polysiloxane was characterized by infrared Fourier transform spectrophotometry (FTIR). In the spectrum peaks are observed in the region of 1258.88 cm-1 corresponding to methyl, between 1000 - 1100 cm-1 a peak corresponding ...

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 AgNO3 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(NH3)2]+ was synthesized under the same conditions as AgNO3 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 AgNO3, shows a monodisperse distribution of the nanocomposite with an average hydrodynamic size of 166.7 nm. In the case of the diamine silver [Ag(NH3)2] + 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 s...

“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. a...

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. aure...

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 ...

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 ...

“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 AgNPsRR. 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...

“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 AgNPsRR. 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...

“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® 25...

“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® 25...

Objective: The current study’s objective is to characterize a new throm-bin-like enzyme called TLBro that was obtained from Bothrops roedingeris snake from a biochemical and hemostatic perspective. Methodology: One chromatographic step was used to purify it, producing the serine protease TLBro. Molecular mass was estimated by SDS-PAGE to be between reduced and unreduced by 35 kDa. Tryptic peptide sequencing using Swiss Prot provided the complete amino acid sequence. Expasy.org by conducting a search that is limited to Crotalinae snake serine proteases and displaying a high degree of amino acid sequence. Results: Ser (182) is inhibited by phenylmethylsulfonyl fluoride (PMSF), and TLBro demonstrated the presence of Asp (88) residues. It also deduced the positions of His (43) and Ser (182) in the set of three coordinated amino acids in serine proteases. It was discovered that this substra...