Luisa Rojas de Astudillo- Ph.D in Chemistry
- Professor at Universidad de Oriente
Luisa Rojas de Astudillo
- Ph.D in Chemistry
- Professor at Universidad de Oriente
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January 1990 - present
Publications
Publications (80)
Objective: The chemical composition and expectorant activity of the purple bracts of B. glabra were evaluated. Methods: The concentrations of alkaloids and saponins were determined spectrophotometrically and the chemical compounds dissolved in chloroform of the dry extract of B. glabra bracts were identified by gas chromatography coupled to mass sp...
Resumen Objetivo: Se evaluó la composición química y la actividad expectorante de las brác-teas moradas de B. glabra. Métodos: Las concentraciones de alcaloides y saponinas se determinaron espectrofotométricamente y los compuestos químicos disueltos en cloroformo del extracto seco de las brácteas de B. glabra fueron identificados por cromatografía...
La planta Bougainvillea glabra Choisy presenta varias propiedades farmacológicas, entre ellas antiinflamatorias, antidiarreicas y actividad expectorante. Por lo que, en este estudio, el objetivo fue evaluar la composición química y actividad antioxidante de hojas de dos variedades de B. glabra, aplicando cromatografía de capa delgada (CCD), cuantif...
La planta Bougainvillea glabra Choisy, utilizada para el tratamiento de varias enfermedades, se presenta en variedades debido al color de sus brácteas, las cuales muestran composiciones químicas diferentes, lo que da la posibilidad de presentar diversas actividades terapéuticas y también potencialmente diferentes efectos tóxicos. De allí la importa...
Airborne particulate matter (APM) is a complex mixture of dust, dirt, soot and smoke containing both organic and inorganic components as well as biological particles. APM below 10 µm can enter the respiratory track and are known to cause adverse health effects. African dust storms are responsible for the transport of large amount of APM across the...
En esta investigación se caracterizó espectroscópicamente, morfológicamente y por microanálisis la biomasa seca de los cladodios de la cactácea Opuntia caracasana y un material resultante después de su tratamiento con KOH (MVT). Los resultados del análisis por FTIR indicaron que la biomasa seca contiene grupos funcionales que señalan la presencia d...
En este estudio, fueron comparados los valores de las concentraciones de fenoles totales en extractos acuosos de plantas medicinales ecuatorianas que fueron obtenidos usando el método espectrofotométrico desarrollado por Folinn y Ciocalteau y por titulación potenciométrica. Por el método potenciométrico se cuantificaron los fenoles totales presente...
Con el objetivo de comparar la relación existente entre el contenido de fenoles totales, flavonoides y la capacidad antioxidante en las brácteas naranjas y moradas de Bougainvillea glabra Choisy, se obtuvieron extractos secos (ES) a partir de muestras de brácteas secas y molidas utilizando como disolvente una mezcla hidroalcohólica (50 %) y sonicac...
To evaluate the levels of heavy metals (Cd, Pb, Cu y Zn) in edible tissue, as well as some molecular biomarkers of oxidative stress, in the digestive gland of the triagonal clam Tivela mactroides from Caicara beach (Venezuela) during different pluviometric seasons, we proceeded to collect between 90 and 100 organisms during August and December 2007...
The aim of this study was to assess the potential risk of heavy metals to the ecosystem of the gulf of Cariaco. To this end, we determined the concentration of heavy metals and the contamination and environmental risk indices in sediments. In addition, a survival test with Artemia salina was applied. The total metal concentrations (µg/g) were: Cu (...
RESUMEN La etiología de la fibromialgia (SFM) es aún desconocida y controversial. Algunas hipótesis sugieren que un desequilibrio en las concentraciones de los bioelementos en los tejidos y fluidos biológicos del cuerpo humano podría ser un cofactor de riesgo. El objetivo de este estudio fue el desarrollo de una metodología analítica para la determ...
In this research, synthesis of activated carbon from the epicarp of Attalea macrolepis was performed and evaluated as adsorbent to remove Pb²⁺ ions. The pH, adsorbent mass, time and initial concentration of Pb²⁺ were evaluated as important parameters in the adsorption process. Additionally, the mechanism of adsorption of Pb²⁺ ions on activated carb...
Introduction: The chemical composition of plant species is subject to changes which depend, among other factors, on their geographic location. The Moringa oleifera Lam. growing in Machala, Ecuador, may differ from species from other geographic regions. Objective: Conduct a preliminary pharmacognostic study of the stem and root (bark and pulp) of th...
The optimal conditions for production of secondary metabolites in medicinal plants, like Moringa oleifera, are advisable to develop stable and secure herbal medicines and nutritional products. The objective of this research was to evaluate the variability of the content of alkaloids, total phenols, flavonoids and tannins in the plant as affected by...
El presente estudio evaluó la capacidad antioxidante de los extractos de dieciséis plantas medicinales: escoba amarga (Parthenium hysterophons), ajenjo (Artemisia absinthium), guarumo (t), chaya (Cnidoscolus chayamansa), borraja (Borago officinalis), balsa (Ochroma sp.), linaza (Linum usitatissimum), hierba Luisa (Cymbopogon citratus), toronjil (Me...
En el método de deposición química catalítica en fase de vapor (CCVD, siglas en inglés), el crecimiento de los CNTs se ve afectado, principalmente, por las características fisicoquímicas del catalizador y el tipo de fuente de carbono. En este trabajo se obtuvieron CNTs a partir de un catalizador FeMo/MgO, preparado por medio de la formación de un s...
Alkaloids, polyphenols, cyanogenic glycosides and saponins are among the main chemical compounds synthesized by plants but not considered essential for their basic metabolism. These compounds have different functions in plants, and have been recognized with medicinal and pharmacological properties. In this research, concentrations of the mentioned...
Los iones plomo pueden ser removidos del agua usando adsorbentes.Entre los diversos adsorbentes se encuentran los nanotubos de carbono (NTsC) muestran un impacto único en la eliminación y adsorción rápida de impurezas nocivas en fuentes acuosas. Los NTsC funcionalizados mejoran la eficiencia y el potencial de adsorción delos iones Pb2+ en comparaci...
RESUMEN Mediante una reacción de polimerización vía radicales libres se sintetizaron hidrogeles (HG) copolímeros de poli(acrilamida-co-ácido itacónico), poli(AAm-co-AI); y poli(acrilamida-co-ácido maleico), poli(AAm-co-AM); con la finalidad de estudiar el efecto que ejerce la estructura química de estos ácidos di-carboxílicos sobre la capacidad abs...
In this research five samples of concentrated of columbite and/or tantalite minerals from municipality Cedeño of Bolivar state, Venezuela where characterized chemical, structural and morphologically by Inductively Coupled Plasma Atomic Emission Spectroscopy (ICPAES), Scanning Electronic Microscopy (SEM), Energy-Dispersive X-Ray Spectroscopy (EDS) a...
Hydrogels have become one of the most versatile materials, because new agents may be incorporated in its structures and providing specific characteristics, which produce different kinds of gels (copolymers, terpolymers, semi-interpenetrating, double network, hybrid, etc.), which have applications in the agriculture, biomedicine and environment. Due...
The dermal healing activity and acute toxicity of Croton lechleri latex were evaluated using Wistar rats. The observation period to determine the healing activity was 7 days (d) and 14 d for the toxicity. Samples for histological evaluations were prepared 7 d after incised wound. The identification of chemical compounds present in the latex was per...
In the present investigation hydrogels Poly (acrylamide–co–Maleic Acid), Poly(AAm–co–AM) and poly(acrylamide–co–itaconic acid), poli(AAm–co–AI) were synthesized by polymerization via addition, with different feed compositions of the monomers were studied at different concentrations of crosslinking agent N, N’–methylenebisacrylamide(NN–MBA). Swellin...
The dermal healing activity and acute toxicity of Croton lechleri latex were evaluated using Wistar rats. The observation period to determine the healing activity was 7 days (d) and 14 d for the toxicity. Samples for histological evaluations were prepared 7 d after incised wound. The identification of chemical compounds present in the latex was per...
In catalytic chemical vapor deposition method (CCVD), CNTs growth is mainly affected by the physicochemical characteristics of the catalyst and the type of carbon source. In this work, CNTs were obtained from a FeMo/MgO catalyst, prepared by the nitrate-citrate sol-gel method, using CCVD with different carbon sources (methanol, ethanol and p-xylene...
Lead ions can be removed from water using adsorbents. Among the various developed adsorbents, carbon nanotubes (CNTs) show a unique impact on rapid adsorption and removal of harmful impurities in aqueous sources. Functionalized CNTs improve efficiency and Pb²⁺ adsorption potential, compared to other materials. In this review article, the removal of...
Multiwall carbon nanotubes (MWCNTs) were synthesized using p-xylene and FeMo/MgO catalysts prepared by two methods (co-impregnation and sol-gel). Carbon nanotubes with uniform diameters were obtained by catalytic chemical vapor deposition at 900°C using FeMo/MgO catalyst prepared by sol-gel method. The sol-gel method resulted in a higher yield than...
El carbón activado es un material adsorbente que contribuye en la limpieza y separación de contaminantes; puede ser obtenido a partir de materiales carbonosos mediante activación física o química, se caracteriza por poseer una alta superficie interna y variedad de grupos funcionales. Comercialmente, el carbón activado se produce a partir de carbón...
Las tendencias mundiales de la alimentación, en los últimos años indican un interés acentuado de los consumidores hacia ciertos alimentos que, además de contener nutrientes, contengan sustancias fisiológicamente activas que cumplan con una función beneficiosa en la reducción de ciertas enfermedades. A estos alimentos, se les ha denominado "alimento...
In this work, a biochemical and hematol ogical profile and distribution of essential (Cu, Fe, Zn, Ca, Mg, Mo, Mn) and non-essential metals (Cd and Pb) was determined in tissues of fish Pterygoplichthys multiradiatus captured from two lagoons (M1 and M2) in Orl noco River, Tucupita, Venezuela. Metal determinations in tissues, water and sediments wer...
RESUMEN Las determinaciones de los bioelementos en suero sanguíneo se consideran muy importantes para establecer niveles de referencia que pueden utilizarse para detectar deficiencias o posibles intoxicaciones por exceso de éstos. El objetivo del presente estudio fue identificar los niveles séricos de magnesio, hierro y cobre en una población de ad...
In this study was evaluated the absorption of bioavailable metals by using polyacrylamide
hydrogels immersed in interstitial waters of the Gulf of Cariaco. The hydrogels were synthesized by
radical polymerization of acrylamide (AAm), using as crosslinking agent N, N–methylenebisacrylamide
and ammonium persulfate as initiator. In the hydrogel was me...
RESUMEN Las determinaciones de los bioelementos en suero sanguíneo se consideran muy importantes para establecer niveles de referencia que pueden utilizarse para detectar deficiencias o posibles intoxicaciones por exceso de éstos. El objetivo del presente estudio fue identificar los niveles séricos de magnesio, hierro y cobre en una población de ad...
Recibido: marzo 2013. Aprobado: noviembre 2013
Las determinaciones de los bioelementos en suero sanguíneo se consideran muy importantes para establecer niveles de referencia que pueden utilizarse para detectar deficiencias o posibles intoxicaciones por exceso de éstos.
El objetivo del presente estudio fue identificar los niveles séricos de magnesi...
Previous evidence has shown the presence in the venom of the Venezuelan scorpion, Tityus discrepans
(Karsch), of potent antileishmanicidal peptides able to increase the intracellular vacuolar content and the flagellar pocket volume, and kill Leishmania (Leishmania) mexicana promastigotes. This work shows the differential leishmanicidal potency of t...
Metallothionein is a cytosolic protein found in a variety of tissues and have been involved in the regulation of essential trace metals such as copper and zinc, and in the detoxification of essential and nonessential metals. With the aim to study their seasonal variation and their possible role in reproductive behavior, we evaluated metallothionein...
Las metalotioninas (Mts) son proteínas de baja masa molecular que juegan un rol importante en la detoxificación de metales, en vista de su papel ecotoxicológico se evaluaron las metalotioneínas (MTs) en 350 ejemplares del bivalvo Perna viridis en dos localidades de la costa norte del estado Sucre, desde febrero hasta diciembre 2003. Se determinaron...
The green mussel Perna viridis has been used as a sentinel organism in marine and coastal ecosystem health assessments. In this study the degree of contamination at three sites on the coast of Sucre State (Venezuela) was analyzed using molecular, cellular, and immunological biomarkers in P. viridis. Specimens were collected from Chacopata-Guayacán...
The green mussel Perna viridis has been used as a sentinel organism in marine and coastal ecosystem health assessments. In this study the degree of contamination at three sites on the coast of Sucre State (Venezuela) was analyzed using molecular, cellular, and immunological biomarkers in P. viridis. Specimens were collected from Chacopata-Guayacán...
In this paper, Polypropylene (PP), before and after being chemically modified with peroxide (PP-perox), in an industrial extruder of PROPILVEN Petrochemical Company, was characterized. Subsequently, PP was functionalized in solution with acrylamide (AAm) and diethylmaleate (DEM) in the presence of biperóxido (DBPH) as initiator. By spectroscopic an...
In this paper we present the results of semi-interpenetrating (semi-IPNs) hydrogels (HG) of poly (acrylamide)/chitosan and poly(acrylamide)/poly (hydroxyalkanoates). The maximum hydration degree reached by the semi-IPN poly(acrylamide)/chitosan HG as compared with polyacrylamide hydrogel showed that the presence of chitosan (Q) occluded in its netw...
Introducción La zona norte de Venezue-la incluye zonas ár idas y semiáridas con escasas pre-cipitaciones (250-500mm), elevadas temperaturas (27-30ºC) y elevada radiación solar (~6500KW/día). Los sue-los son en su mayoría de baja calidad, pobres en materia orgánica y con altos conteni-dos salinos (Díaz, 2001), lo que hace a estas zonas poco aptas pa...
The ecophysiology of Aloe vera was studied in two plots, plot A far from the sea and B plot near the sea, situated in Guayacan, Araya Peninsula, Venezuela during the dry and wet seasons. The soil textures in plots A and B were medium and coarse, respectively. Plot B presented lesser humidity (%), Ca2+, K+ and Mg2+, and higher Cl. and Na + in compar...
RESUMEN En este trabajo se presentan los resultados obtenidos en polímeros hidrogeles (HG) de tipo semi-Interpenetrados (semi-IPNs) de poli(acrilamida)/quitosano y poli(acrilamida)/poli(hidroxialcanoatos). Los máximos grados de hidratación alcanzados por los HG semi-IPN poli(acrilamida)/quitosano, en comparación con el hidrogel de poliacrilamida ar...
RESUMEN En este trabajo se obtuvieron hidrogeles (HG) con potenciales aplicaciones en el tratamiento de infecciones óseas, sintetizados a partir de poli(acrilamida) y poli(acrilamida-co-ácido itacónico). Los HG fueron sintetizados y caracterizados antibiótico comercial (Tygacil, Tigeciclina). Se utilizó Espectrometría de Emisión Óptica con Plasma I...
The presence, concentration and sources of 14 selected polycyclic aromatic hydrocarbons (PAHs), among those listed as priority pollutants by the US Environmental Protection Agency were investigated in surface sediment samples from the Gulf of Cariaco, Sucre state, Venezuela, in June 2007 and April 2008. The results show the presence of three low mo...
The presence, concentration and sources of 14 selected polycyclic aromatic hydrocarbons (PAHs), among those listed as priority pollutants by the US Environmental Protection Agency were investigated in surface sediment samples from the Gulf of Cariaco, Sucre state, Venezuela, in June 2007 and April 2008. The results show the presence of three low mo...
Benzene, declared as an environmental contaminant, has commonlybeen used as an industrial solvent, a starting material for the synthesis ofother chemicals, and as an antiknock agent in gasoline, and is asignificant component of cigarette smoke. While not fully understood, thetoxicity of benzene is linked to the production of reactive metabolitesfor...
In this paper, Polypropylene (PP), before and after being chemically modified with peroxide (PP-perox), in an industrial extruder of PROPILVEN Petrochemical Company, was characterized. Subsequently, PP was functionalized in solution with acrylamide (AAm) and diethylmaleate (DEM) in the presence of biperóxido (DBPH) as initiator. By spectroscopic an...
In this paper we present the results of semi-interpenetrating (semi-IPNs) hydrogels (HG) of poly (acrylamide)/chitosan and poly(acrylamide)/poly (hydroxyalkanoates). The maximum hydration degree reached by the semi-IPN poly(acrylamide)/chitosan HG as compared with polyacrylamide hydrogel showed that the presence of chitosan (Q) occluded in its netw...
The objective of this work was the optimization of an acid digestion method to determine trace elements in the PP. This optimization is affected by the hardness of PP, derived from its crystalline nature resulting from its isotactic character. As part of the optimization process, PP samples were spiked at different concentrations of titanium, alumi...
Because the criterion of sediment quality, derived from the partition equilibrium model, argues that the pore water is a major source of accumulation and toxicity of chemical species in the tissues of benthic organisms, and trying to reproduce the diffusion processes in them, it was considered interesting to study the behavior of metals and sulfur...
![Figura 1. Formación del hidrogel semi-IPN simultaneo AAm y PHB [4].](profile/Blanca-Gascue/publication/264841622/figure/fig1/AS:643520025067537@1530438538271/Figura-1-Formacion-del-hidrogel-semi-IPN-simultaneo-AAm-y-PHB-4_Q320.jpg)
RESUMEN En este trabajo se sintetizaron y caracterizaron hidrogeles semi-IPN potencialmente biodegradables obtenidos a partir de acrilamida (AAm) polimerizada y reticulada en presencia del biopolímero poli(3-hidroxibutirato), PHB. Los hidrogeles fueron obtenidos a partir de proporciones alimentadas de AAm/PHB, desde 100/0 hasta 60/40. El grado de h...
Hydrogels were synthesized from ammonium persulphate (PSA), N, N'- methylenebisacrylamide (MBAAm), acrylamide and poly(acrylic acid), (AAm / PAAc) varying the acrylamide feeding ratio. The incorporation of AAm and PAAc in the networks was demonstrated by the characterization of the obtained gels with Fourier Transformed Infrared Spectroscopy
(FT-IR...
![Figura 2. Polimerización de un hidrogel IPN de forma simultánea [9].](profile/Arnaldo-Ramirez-4/publication/268924877/figure/fig1/AS:654042858549248@1532947377042/Figura-2-Polimerizacion-de-un-hidrogel-IPN-de-forma-simultanea-9_Q320.jpg)
RESUMEN Se sintetizaron y caracterizaron hidrogeles obtenidos a partir de acrilamida (AAm) y quitosano emisión óptica con plasma acoplado inductivamente (ICP–OES), la presencia de Fe 2+
Heavy metal distribution in superficial sedimenta ta Saco, Gulf of Cariaco, Sucre, Venezuela. The Gulf of Cariaco is a marine ecosystem with high primary productivity, which gives it an ecological and socioeconomic importance. Nevertheless, anthropogenic activities around the Gulf produce wastes that are deposited directly or by runoff into the sed...
The Gulf of Cariaco is a marine ecosystem with high primary productivity, which gives it an ecological and socioeconomic importance. Nevertheless, anthropogenic activities around the Gulf produce wastes that are deposited directly or by runoff into the sediments, and consequently, increases concentrations of metals in this ecosystem. The objective...
The electrochemical behavior of 1,4-benzoquinone has been studied immobilizing this molecule on a gold electrode modified with 1-propanethiol (1-PT), 2-propene-1-thiol (2-P-1-T) and 1,3-propanedithiol (1,3-PDT). In the method used (self-assembled techniques) for the surface modification we control the exposure time of gold surface in the modifier/e...
In this study was evaluated the distribution of total thiols (TT) and acid soluble thiols (AST) in tissues of the freshwater fish Colos- soma macropomum providing of cultivation and acclimated in laboratory by 15 and 30 days, as well, was evaluated the effect of cadmium on these parameters in Cd-exposure fishes during 21 days and in Cd-depuration f...
Mercury levels were determined in green mussels, Perna viridis, from two localities of Sucre State (Venezuela): Chacopata and Río Caribe. Specimens were captured in the intertidal zone from February to December 2003. They presented anteroposterior lengths ranging from 18 to 113 mm and were classified, according to their sexual maturity, as juvenile...
Mercury levels were determined in green mussels, Perna viridis, from two localities of Sucre State (Venezuela): Chacopata and Rio Caribe. Specimens were captured in the intertidal zone from February to December 2003. They presented anteroposterior lengths ranging from 18 to 113 mm and were classified, according to their sexual maturity, as juvenile...
In this study was evaluated the distribution of total thiols (TT) and acid soluble thiols (AST) in tissues of the freshwater fish Colossoma macropomum providing of cultivation and acclimated in laboratory by 15 and 30 days, as well, was evaluated the effect of cadmium on these parameters in Cd-exposure fishes during 21 days and in Cd-depuration fis...
Trinidad, Tobago y Grenada; (b) El Mar Caribe, por la advección meridional norte-sur a través de la región comprendida entre la isla La Tortuga y la isla de Margarita y (c) Los estuarios provenientes del golfo de Paria (fundamentalmente descargados por el río Orinoco), a través de la norte y el Golfo de Paria del estado Sucre. Se extrajo el mercuri...
Total and organic mercury contents were determined from samples of surface soils (0-5 cm), sieved at ≤ 63µm, collected from 10 different locations in the upper Manzanares River watershed, using cold vapor atomic absorption spectroscopy. Methylmercury was determined using a HPLC-UV detector. The mean total mercury concentration was 1.3 μg.g-1, a val...
Paralytic shellfish poisoning (PSP) toxins were determined in green mussels (Perna viridis) from the Gulf of Paria between Trinidad and Venezuela, as well as from the northern coast of Venezuela. Aqueous extracts of samples were purified by passage through SPE C-18 and carboxylic columns, and oxidized by periodate and peroxide reagents, before anal...
A collaborative study was conducted for the determination of paralytic shellfish poisoning (PSP) toxins in shellfish. The method used liquid chromatography with fluorescence detection after prechromatographic oxidation of the toxins with hydrogen peroxide and periodate. The PSP toxins studied were saxitoxin (STX), neosaxitoxin (NEO), gonyautoxins 2...
A collaborative study was conducted for the determination of paralytic shellfish poisoning (PSP) toxins in shellfish. The method used liquid chromatography with fluorescence detection after prechromatographic oxidation of the toxins with hydrogen peroxide and periodate. The PSP toxins studied were saxitoxin (STX), neosaxitoxin (NEO), gonyautoxins 2...
The Gulf of Paria is bordered by both Trinidad and Venezuela, from which various metallic pollutants and other contaminants can originate. The Gulf is still a significant source of fish, crabs and shellfish for human consumption to both countries, where concerns over the quality of this marine environment have been long expressed but never properly...
Paralytic shellfish poisoning (PSP) toxins were determined in green mussels (Perna viridis) collected from one collection site in the Gulf of Paria in Trinidad in 1999 and 2000. Aqueous extracts of PSP were purified by passage through C-18 SPE cartridges, oxidized with peroxide and periodate, respectively, then analyzed by HPLC with fluorescence de...
A severe outbreak of Paralytic Shellfish Poisoning (PSP) occurred in Manzanillo and Guayacán, northwestern coast of Margarita Island, Venezuela, between August and October 1991. A bloom of dinoflagellates including Prorocentrum gracile, Gymnodinium catenatum and Alexandrium tamarense seemed to be responsible for this outbreak. Levels of PSP toxins...
Heavy metal concentrations were monitored in edible soft tissues of shellfish from Trinidad and Venezuela. Oysters (Crassostrea sp.) and the green mussel (Perna viridis), which is a recently transplanted species to the Caribbean from the Far East, were collected at six locations in Venezuela and five in Trinidad, the latter along the coast line of...
La saxitoxina y sus derivados son potentes neurotoxinas que originan afecciones asociadas a la intoxicación paralizante en humanos (PSP, siglas en inglés) que son producidas primariamente por dinoflagelados. Con la finalidad de evaluar y optimizar el uso de la cromatografía líquida de alta resolución con previa oxidación para la determinación de la...
En este estudio se determinó la relación entre la resolución de problemas estequimétricos y el manejo de los conceptos químicos sobre los cuales se basan los problemas Para el estudio se seleccionaron 305 alumnos pertenecientes a 10 secciones de Química I, un curso para estudiantes de Ciencias e ingeniería de a Universidad de Oriente. El análisis d...
The main purpose was to compare whether Pascual-Leone and Baddeley's models of information processing can explain performance of 83 Venezuelan freshman students in subjects such as chemistry, physics, mathematics, and language (Spanish). All students were tested on (a) Working Memory Span based on an adaptation of the Daneman and Carpenter task by...
Achievement in science depends on a series of factors that characterize the cognitive abilities of the students and the complex interactions between these factors and the environment that intervenes in the formation of students' background. The objective of this study is to: a) investigate reasoning strategies students use in solving stoichiometric...
Saxitoxin and its derivatives are potent neurotoxins associated with paralytic shellfish poisoning (PSP) in humans which are primarily produced by dinoflagellates. To evaluate and optimize the use of high performance liquid chromatography (HPLC) with previous oxidation in order to determine saxitoxin and its derivatives, samples of the green mussel...
