Development and validation of an analytical method using High Performance Liquid Chromatography (HPLC) to determine ethyl butylacetylaminopropionate in topical repellent formulations

Diseases caused by insects are frequent in poor countries, leading to epidemic scenarios in urban areas; e.g., Dengue, Zika and Chikungunya. For this reason, the development of a safe and efficient topical formulation is essential. Ethyl butylacetylaminopropionate (EB) is a mosquito repellent developed by Merck, which is used in products for adults, children and especially babies, due to its low allergenic potential. The aim of this work was to validate an analytical methodology to quantify EB in a new poloxamer-based formulation by high-performance liquid chromatography (HPLC). The quantification methodology was performed at 40 ºC using a Kromasil reverse-phase column (C18), with the dimensions of 250 x 4.6 mm. The mobile phase was acetonitrile:water (1:1) at a 1.0 mL/min flow-rate. The detector wavelength was set at 218 nm to detect EB. The methodology was considered validated since the results indicated linearity (R2>;0.99), specificity, selectivity, precision and accuracy (active recovery between 98% and 102%). It also presented limits of detection and quantification of 0.255 µg/mL and 0.849 µg/mL, respectively. The present study demonstrated the EB vehiculated in poloxamer gel is promising as a new insect repellent formulation, since it could be quantified and quality control evaluated

Development and validation of an analytical method using High Performance Liquid Chromatography (HPLC) to determine ethyl butylacetylaminopropionate in topical repellent formulations

ABSTRACT Diseases caused by insects are frequent in poor countries, leading to epidemic scenarios in urban areas; e.g., Dengue, Zika and Chikungunya. For this reason, the development of a safe and efficient topical formulation is essential. Ethyl butylacetylaminopropionate (EB) is a mosquito repellent developed by Merck, which is used in products for adults, children and especially babies, due to its low allergenic potential. The aim of this work was to validate an analytical methodology to quantify EB in a new poloxamer-based formulation by high-performance liquid chromatography (HPLC). The quantification methodology was performed at 40 ºC using a Kromasil reverse-phase column (C18), with the dimensions of 250 x 4.6 mm. The mobile phase was acetonitrile:water (1:1) at a 1.0 mL/min flow-rate. The detector wavelength was set at 218 nm to detect EB. The methodology was considered validated since the results indicated linearity (R2>0.99), specificity, selectivity, precision and accuracy (active recovery between 98% and 102%). It also presented limits of detection and quantification of 0.255 µg/mL and 0.849 µg/mL, respectively. The present study demonstrated the EB vehiculated in poloxamer gel is promising as a new insect repellent formulation, since it could be quantified and quality control evaluated

Isolation and molecular characterization of Toxoplasma gondii from placental tissues of pregnant women who received toxoplasmosis treatment during an outbreak in southern Brazil.

Toxoplasma gondii is a protozoan that has great genetic diversity and is prevalent worldwide. In 2018, an outbreak of toxoplasmosis occurred in Santa Maria, Brazil, which was considered the largest outbreak ever described in the world. This paper describes the isolation and molecular characterization of Toxoplasma gondii from the placenta of two pregnant women with acute toxoplasmosis who had live births and were receiving treatment for toxoplasmosis during the outbreak. For this, placental tissue samples from two patients underwent isolation by mice bioassay, conventional PCR and genotyping using PCR-RFLP with twelve markers. Both samples were positive in isolation in mice. The isolate was lethal to mice, suggesting high virulence. In addition, the samples were positive in conventional PCR and isolates submitted to PCR-RFLP genotyping presented an atypical genotype, which had never been described before. This research contributes to the elucidation of this great outbreak in Brazil

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data