Person: Rosales Conrado, Noelia
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First Name
Noelia
Last Name
Rosales Conrado
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Analítica
Area
Química Analítica
Identifiers
4 results
Search Results
Now showing 1 - 4 of 4
Item Learning Principal Component Analysis by Using Data from Air Quality Networks(Journal of Chemical Education, 2017) Pérez Arribas, Luis Vicente; León González, María Eugenia; Rosales Conrado, NoeliaWith the final objective of using computational and chemometrics tools in the chemistry studies, this paper shows the methodology and interpretation of the Principal Component Analysis (PCA) using pollution data from different cities. This paper describes how students can obtain data on air quality and process such data for additional information related to the pollution sources, climate effects, and social aspects over pollution levels by using a powerful chemometrics tool such as principal component analysis (PCA). The paper could also be useful for students interested in environmental chemistry and pollution interpretation; this statistical method is a simple way to display visually as much as possible of the total variation of the data in a few dimensions, and it is an excellent tool for looking into the normal pollution patterns.- Project number: 151
Item Elaboración de material de apoyo para la evaluación individual de trabajos realizados en grupo en el Grado en Química(2015) Rosales Conrado, Noelia; León González, María Eugenia; Pérez Arribas, Luis Vicente; Ávila Brande, David; Martínez Del Campo, Teresa; Luna Costales, AmparoDiseño y la elaboración de plantillas que puedan servir de apoyo a la docencia de la Química y que permitan evaluar objetivamente los resultados del proceso de enseñanza/aprendizaje en las prácticas de laboratorio realizadas en grupo. Item Determination of ibuprofen enantiomers in breast milk using vortex-assisted matrix solid-phase dispersion and direct chiral liquid chromatography(Journaol of Chromatography A, 2017) León González, María Eugenia; Rosales Conrado, NoeliaA mixture of B-cyclodextrin (B-CD) and primary and secondary amine (PSA) sorbents was employed for the extraction and quantification of ibuprofen enantiomers from human breast milk, combining a vortex-assisted matrix solid-phase dispersion method (MSPD) and direct chiral liquid chromatography (CLC) with ultraviolet detection (UV). The MSPD sample preparation procedure was optimized focusing on both the type and amount of dispersion/sorption sorbents and the nature of the elution solvent, in order to obtain acceptable recoveries and avoiding enantiomer conversion. These MSPD parameters were optimized with the aid of an experimental design approach. Hence, a factorial design was used for identification of the main variables affecting the extraction process of ibuprofen enantiomers. Under optimum selected conditions, MSPD combined with direct CLC-UV was successfully applied for ibuprofen enantiomeric determination in breast milk at enantiomer levels between 0.15 and 6.0 µg∙g-1. The proposed analytical method also provided good repeatability, with relative standard deviations of 6.4 % and 8.3 % for the intra-day and inter-day precision, respectively.Item Enantioselective determination of ibuprofen residues by chiral liquid chromatography: a systematic study of enantiomeric transformation in surface water and sediments(Environ. Chem, 2016) León González, María Eugenia; Rosales Conrado, NoeliaThe enantioselective composition of ibuprofen in sediments in contact with surface water was evaluated over 168 h in the presence and absence of light. Multivariate techniques applied for the evaluation of enantiomeric fraction (EF) and recoveries of enantiomers in water and sediments show differences in the EF and composition of each enantiomer. In sediments, differences in the EF are a result of the presence or absence of light, whereas in water it is attributable to degradation of the two enantiomers with time. To achieve enantioselective separation of ibuprofen in surface water and sediments, a clean-up and preconcentration procedure using solid phase extraction combined with a direct chiral liquid chromatography–ultraviolet method was developed. Quantitation limits of the proposed method were between 0.12 and 0.15 mg g �1 for each enantiomer in sediments, and between 2.4 and 3.0 mg L �1 in surface water. Intra- and inter-day precisions were between 5.1 and 8.9 %. Multivariate techniques can be useful to identify enantiomeric modifications and to select the variables that should be used for modelling such transformations.