Determination of organothiophosphorus pesticides in water by liquid chromatography and post-column chemiluminescence with cerium(IV)

A new, fast, selective and sensitive method has been developed for the simultaneous determination of nine organothiophosphorus (OTP) pesticides, namely omethoate, dimethoate, disulfoton-sulfoxide, methidathion, phosmet, malathion, diazinon, pirimiphos-methyl and chlorpyrifos. The pesticides were separated on a Kinetex C18 column by gradient elution with acetonitrile:water. A post-column basic hydrolysis of the pesticides and later a chemiluminescence (CL) reaction with cerium (IV) in acid medium was carried out. Hexadecylpyridinium chloride highly enhanced the CL emission. Under optimized conditions, linearity, precision, limits of detection and quantification, and accuracy were determined. Both selectivity and sensitivity were compared with those obtained with UV detection. In combination with SPE, limits of detection in the range 15-80 ng/L and 5-30 ng/L were obtained when 250 mL and 1000 mL of solution were treated, respectively. When applied to 250 mL of sample the inter-day precision of the method was between 3.5% and 7.3% and the intra-day precision between 2.9% and 6.0%. The method was applied to determine OTP pesticides in spiked water samples from different origins: irrigation, river, sea, ground, spring, mineral and tap waters, being the percentage of recovery of added amounts near 100% form most of the pesticides.Catalá Icardo, M.; Lahuerta Zamora, L.; Torres-Cartas, S.; Meseguer-Lloret, S. (2014). Determination of organothiophosphorus pesticides in water by liquid chromatography and post-column chemiluminescence with cerium(IV). Journal of Chromatography A. 1341:31-40. doi:10.1016/j.chroma.2014.03.0243140134

Selective and sensitive chemiluminescence determination of MCPB: flow injection and liquid chromatography

This paper was published in Applied Spectroscopy and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1177/0003702815620133 . Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.Two new chemiluminescence (CL) methods are described for the determination of the herbicide 4-(4-chloro-o-tolyloxy) butyric acid (MCPB). First, a flow injection chemiluminescence (FI-CL) method is proposed. In this method, MCPB is photodegraded with an ultraviolet (UV) lamp and the photoproducts formed provide a great CL signal when they react with ferricyanide in basic medium. Second, a high-performance liquid chromatography chemiluminescence (HPLC-CL) method is proposed. In this method, before the photodegradation and CL reaction, the MCPB and other phenoxyacid herbicides are separated in a C18 column. The experimental conditions for the FI-CL and HPLC-CL methods are optimized. Both methods present good sensitivity, the detection limits being 0.12 mg L 1 and 0.1 mg L 1 (for FI-CL and HPLC-CL, respectively) when solid phase extraction (SPE) is applied. Intra- and interday relative standard deviations are below 9.9%. The methods have been satisfactorily applied to the analysis of natural water samples. FI-CL method can be employed for the determination of MCPB in simple water samples and for the screening of complex water samples in a fast, economic, and simple way. The HPLC-CL method is more selective, and allows samples that have not been resolved with the FI-CL method to be solved.Meseguer-Lloret, S.; Torres-Cartas, S.; Catalá-Icardo, M.; Gómez Benito, C. (2016). Selective and sensitive chemiluminescence determination of MCPB: flow injection and liquid chromatography. Applied Spectroscopy. 70(2):312-321. doi:10.1177/0003702815620133S312321702Moral, A., Caballo, C., Sicilia, M. D., & Rubio, S. (2012). Highly efficient microextraction of chlorophenoxy acid herbicides in natural waters using a decanoic acid-based nanostructured solvent prior to their quantitation by liquid chromatography–mass spectrometry. Analytica Chimica Acta, 709, 59-65. doi:10.1016/j.aca.2011.10.016Herrero-Hernández, E., Rodríguez-Gonzalo, E., Andrades, M. S., Sánchez-González, S., & Carabias-Martínez, R. (2013). Occurrence of phenols and phenoxyacid herbicides in environmental waters using an imprinted polymer as a selective sorbent. Science of The Total Environment, 454-455, 299-306. doi:10.1016/j.scitotenv.2013.03.029Baggiani, C., Giovannoli, C., Anfossi, L., & Tozzi, C. (2001). Molecularly imprinted solid-phase extraction sorbent for the clean-up of chlorinated phenoxyacids from aqueous samples. Journal of Chromatography A, 938(1-2), 35-44. doi:10.1016/s0021-9673(01)01126-8Wintersteiger, R., Goger, B., & Krautgartner, H. (1999). Quantitation of chlorophenoxy acid herbicides by high-performance liquid chromatography with coulometric detection. Journal of Chromatography A, 846(1-2), 349-357. doi:10.1016/s0021-9673(99)00429-xPeruzzi, M., Bartolucci, G., & Cioni, F. (2000). Determination of phenoxyalkanoic acids and other herbicides at the ng/ml level in water by solid-phase extraction with poly(divinylbenzene-co-N-vinylpyrrolidone) sorbent and high-performance liquid chromatography–diode-array detection. Journal of Chromatography A, 867(1-2), 169-175. doi:10.1016/s0021-9673(99)01141-3Ranz, A., & Lankmayr, E. (2006). Screening and optimization of the derivatization of polar herbicides with trimethylanilinium hydroxide for GC-MS analysis. Journal of Biochemical and Biophysical Methods, 69(1-2), 3-14. doi:10.1016/j.jbbm.2006.02.007Nuhu, A. A., Basheer, C., Alhooshani, K., & Al-Arfaj, A. R. (2012). Determination of phenoxy herbicides in water samples using phase transfer microextraction with simultaneous derivatization followed by GC-MS analysis. Journal of Separation Science, 35(23), 3381-3388. doi:10.1002/jssc.201200218Jiménez, J. J. (2013). Simultaneous liquid–liquid extraction and dispersive solid-phase extraction as a sample preparation method to determine acidic contaminants in river water by gas chromatography/mass spectrometry. Talanta, 116, 678-687. doi:10.1016/j.talanta.2013.07.052EREMIN, S., LAASSIS, B., & AARON, J. (1996). Photochemical-fluorimetric method for the determination of total chlorophenoxyacid herbicides. Talanta, 43(3), 295-301. doi:10.1016/0039-9140(95)01751-8Jafari, M. T., Saraji, M., & Yousefi, S. (2012). Negative electrospray ionization ion mobility spectrometry combined with microextraction in packed syringe for direct analysis of phenoxyacid herbicides in environmental waters. Journal of Chromatography A, 1249, 41-47. doi:10.1016/j.chroma.2012.06.024Tsogas, G. Z., Giokas, D. L., Nikolakopoulos, P. G., Vlessidis, A. G., & Evmiridis, N. P. (2006). Determination of the pesticide carbaryl and its photodegradation kinetics in natural waters by flow injection–direct chemiluminescence detection. Analytica Chimica Acta, 573-574, 354-359. doi:10.1016/j.aca.2005.11.058Albert-García, J. R., & Calatayud, J. M. (2008). Determination of the herbicide benfuresate by its photo-induced chemiluminescence using flow multicommutation methodology. Talanta, 75(3), 717-724. doi:10.1016/j.talanta.2007.12.003Catalá-Icardo, M., López-Paz, J. L., Choves-Barón, C., & Peña-Bádena, A. (2012). Native vs photoinduced chemiluminescence in dimethoate determination. Analytica Chimica Acta, 710, 81-87. doi:10.1016/j.aca.2011.10.043Gómez-Benito, C., Meseguer-Lloret, S., & Torres-Cartas, S. (2013). Sensitive determination of Fenamiphos in water samples by flow injection photoinduced chemiluminescence. International Journal of Environmental Analytical Chemistry, 93(2), 152-165. doi:10.1080/03067319.2012.663755Beale, D. J., Porter, N. A., & Roddick, F. A. (2009). A fast screening method for the presence of atrazine and other triazines in water using flow injection with chemiluminescent detection. Talanta, 78(2), 342-347. doi:10.1016/j.talanta.2008.11.033Catalá-Icardo, M., López-Paz, J. L., & Pérez-Plancha, L. M. (2014). Fast Determination of Thiacloprid by Photoinduced Chemiluminescence. Applied Spectroscopy, 68(6), 642-648. doi:10.1366/13-07330Torres-Cartas, S., Gómez-Benito, C., & Meseguer-Lloret, S. (2011). FI on-line chemiluminescence reaction for determination of MCPA in water samples. Analytical and Bioanalytical Chemistry, 402(3), 1289-1296. doi:10.1007/s00216-011-5567-1Catalá-Icardo, M., Lahuerta-Zamora, L., Torres-Cartas, S., & Meseguer-Lloret, S. (2014). Determination of organothiophosphorus pesticides in water by liquid chromatography and post-column chemiluminescence with cerium(IV). Journal of Chromatography A, 1341, 31-40. doi:10.1016/j.chroma.2014.03.024Huertas-Pérez, J. F., & García-Campaña, A. M. (2008). Determination of N-methylcarbamate pesticides in water and vegetable samples by HPLC with post-column chemiluminescence detection using the luminol reaction. Analytica Chimica Acta, 630(2), 194-204. doi:10.1016/j.aca.2008.09.047Orejuela, E., & Silva, M. (2003). Monitoring some phenoxyl-type N-methylcarbamate pesticide residues in fruit juices using high-performance liquid chromatography with peroxyoxalate-chemiluminescence detection. Journal of Chromatography A, 1007(1-2), 197-201. doi:10.1016/s0021-9673(03)00934-8GALERA, M., GARCIA, M., & VALVERDE, R. (2008). Determination of photoirradiated high polar benzoylureas in tomato by HPLC with luminol chemiluminescence detection. Talanta, 76(4), 815-823. doi:10.1016/j.talanta.2008.04.052Rosales-Conrado, N., León-González, M. E., Pérez-Arribas, L. V., & Polo-Díez, L. M. (2005). Effect of temperature on the separation of chlorophenoxy acids and carbamates by capillary high-performance liquid chromatography and UV (or diode array) detection. Journal of Chromatography A, 1081(1), 114-121. doi:10.1016/j.chroma.2004.12.083Geerdink, R. B., van Tol-Wildenburg, S., Niessen, W. M. A., & Brinkman, U. A. T. (1997). Determination of Phenoxy Acid Herbicides From Aqueous Samples by Improved Clean-up on Polymeric Pre-columns at High pH. The Analyst, 122(9), 889-894. doi:10.1039/a702338

Influence of photo-initiators in the preparation of methacrylate monoliths into poly(ethylene-co-tetrafluoroethylene) tubing for microbore HPLC

[EN] In this study, poly(butyl methacrylate-co-ethyleneglycol dimethacrylate) polymeric monoliths were in situ developed within 0.75 mm i.d. poly(ethylene-co-tetrafluoroethylene) (ETFE) tubing by UV polymerization via three different free-radical initiators fscce-azobisisobutyronitrile (AIBN), 2,2-dimethoxy-2-phenylacetophenone (DMPA) and 2-methyl-4'-(methylthio)-2-morpholinopropiophenone (MTMPP). The influence of the nature of each photo-initiator and irradiation time on the morphological features of the polymer was investigated by scanning electron microscopy, and the chromatographic properties of the resulting microbore columns were evaluated using alkyl benzenes as test substances. The beds photo-initiated with MTMPP gave the best performance (minimum plate heights of 38 mu m for alkyl benzenes) and exhibited a satisfactory reproducibility in the chromatographic parameters (RSD < 11%). These monolithic columns were also successfully applied to the separation of phenylurea herbicides, proteins and a tryptic digest of beta-casein. (C) 2019 Elsevier B.V. All rights reserved.This research study has been sponsored by projects PROMETEO/2016/145 (Conselleria d'Educacio, Investigacio, Cultura i Esport, Generalitat Valenciana, Spain) and RTI2018-095536-B-I00 (Ministry of Science, Innovation and Universities, Spain).Catalá-Icardo, M.; Torres-Cartas, S.; Simó-Alfonso, EF.; Herrero-Martínez, JM. (2020). Influence of photo-initiators in the preparation of methacrylate monoliths into poly(ethylene-co-tetrafluoroethylene) tubing for microbore HPLC. Analytica Chimica Acta. 1093:160-167. https://doi.org/10.1016/j.aca.2019.09.055S160167109

Photografted fluoropolymers as novel chromatographic supports for polymeric monolithic stationary phases

[EN] In this study, porous polymer monoliths were in situ synthesized in fluoropolymers tubing to prepare microbore HPLC columns. To ensure the formation of robust homogeneous polymer monoliths in these housing supports, the inner surface of fluoropolymer tubing was modified in a two-step photografting process. Raman spectroscopy and scanning electron microscopy (SEM) confirmed the successful modification of the inner poly(ethylene-co-tetrafluoroethylene) (ETFE) wall and the subsequent attachment of a monolith onto the wall. Poly(glycidyl methacrylate-co-divinylbenzene), poly(butyl methacrylate-co-ethyleneglycol dimethacrylate) and poly(styrene-co-divinylbenzene) monoliths were in situ synthesized by thermal polymerization within the confines of surface vinylized ETFE tubes. The resulting monoliths exhibited good permeability and mechanical stability (pressure resistance up to 9¿MPa). The chromatographic performance of these different monolithic columns was evaluated via the separation of alkyl benzenes and proteins in a conventional HPLC system.This work was supported by project PROMETEO/2016/145 (Conselleria d'Educacio, Investigacio, Cultura i Esport,Esport, Generalitat Valenciana, Spain). The authors also thank Dr. S. Laredo-Ortiz from the Atomic Spectroscopy section of the SCSIE (University of Valencia), for her help in Raman measurements.Catalá-Icardo, M.; Torres-Cartas, S.; Meseguer-Lloret, S.; Simó-Alfonso, E.; Herrero Martínez, J. (2018). Photografted fluoropolymers as novel chromatographic supports for polymeric monolithic stationary phases. Talanta. 187:216-222. doi:10.1016/j.talanta.2018.05.026S21622218

Recent Advances in Molecularly Imprinted Membranes for Sample Treatment and Separation

[EN] This review describes the recent advances from the past five years concerning the development and applications of molecularly imprinted membranes (MIMs) in the field of sample treatment and separation processes. After a short introduction, where the importance of these materials is highlighted, a description of key aspects of membrane separation followed by the strategies of preparation of these materials is described. The review continues with several analytical applications of these MIMs for sample preparation as well as for separation purposes covering pharmaceutical, food, and environmental areas. Finally, a discussion focused on possible future directions of these materials in extraction and separation field is also given.This work was supported by project RTI2018-095536-B-I00 (Ministry of Science, Innovation and Universities, Spain).Torres-Cartas, S.; Catalá-Icardo, M.; Meseguer-Lloret, S.; Simó-Alfonso, EF.; Herrero-Martínez, JM. (2020). Recent Advances in Molecularly Imprinted Membranes for Sample Treatment and Separation. Separations. 7(4):1-28. https://doi.org/10.3390/separations7040069S1287

Extraction and preconcentration of organophosphorus pesticides in water by using a polymethacrylate-based sorbent modified with magnetic nanoparticles

[EN] A polymethacrylate-based sorbent modified with magnetic nanoparticles (MNPs) has been synthesized and used as sorbent for solid-phase extraction (SPE) and magnetic solid-phase extraction (MSPE) of three organophosphorus pesticides (phosmet, pirimiphos-methyl, and chlorpyrifos) in water samples followed by high-performance liquid chromatography diode array detection. The sorbent was prepared from a glycidyl methacrylate-based polymer, modified with a silanizing agent, followed by immobilization of MNPs on the surface of the material. The sorbent was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. Comparative studies of this support were done both in conventional SPE cartridge and MSPE approach. Several extraction parameters (loading pH, elution solvent, eluting volume, and loading flow rate) were investigated in detail. Under optimal conditions, the proposed sorbent gave an excellent enrichment efficiency of analytes and detection limits between 0.01 and 0.25 &#956;g L&#8722;1. The recoveries of organophosphorus pesticides in spiked water samples were in the range of 71 98%, and the developed sorbent showed a high reusability (up to 50 uses without losses in recovery). The proposed method was satisfactorily applied to the analysis of these pesticides in water samples from different sources.This work was supported by projects CTQ2014-52765-R (MINECO of Spain and FEDER) and PROMETEO/2016/145 (Conselleria de Educacion, Investigacion, Cultura y Deporte of Generalitat Valenciana, Spain).Meseguer-Lloret, S.; Torres-Cartas, S.; Catalá-Icardo, M.; Simó-Alfonso, EF.; Herrero-Martínez, JM. (2017). Extraction and preconcentration of organophosphorus pesticides in water by using a polymethacrylate-based sorbent modified with magnetic nanoparticles. 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Anal Chim Acta. 2008;630(2):194–204.Samadi S, Sereshti H, Assadi Y. Ultra-preconcentration and determination of thirteen organophosphorus pesticides in water sample using solid-phase extraction followed by dispersive liquid-liquid microextraction and gas chromatography with flame photometric detection. J Chromatogr A. 2012;1219:61–5.He L, Luo X, Xie H, Wang C, Jiang X, Lu K. Ionic liquid-based dispersive liquid–liquid microextraction followed high-performance liquid chromatography for the determination of organophosphorus pesticides in water sample. Anal Chim Acta. 2009;655:52–9.Wu C, Liu N, Wu Q, Wang C, Wang Z. Application of ultrasound-assisted surfactant-enhanced emulsification microextraction for the determination of some organophosphorus pesticides in water samples. Anal Chim Acta. 2010;679:56–62.Peng G, Lu Y, He Q, Mmereki D, Zhou G, Chen J, et al. Determination of 3,5,6-trichloro-2-pyridinol, phoxim and chlorpyrifos-methyl in water samples using a new pretreatment method coupled with high-performance liquid chromatography. J Sep Sci. 2016;38:4204–10.Báez ME, Rodríguez M, Lastra O, Contreras P. Solid phase extraction of organophosphorus, triazine, and triazole-derived pesticides from water samples. A critical study. J High Resolut Chrom. 1997;20:591–6.Rocha AA, Monteiro SH, Andrade GCRM, Vilca FZ, Tornisielo CL. Monitoring of pesticides residues in surface and subsurface waters, sediments and fish in center-pivot irrigation areas. J Braz Chem Soc. 2015;25(11):2269–78.Hadjmohammadi MR, Peyrovi M, Biparva P. Comparison of C18 silica and multi-walled carbon nanotubes as the adsorbents for the solid-phase extraction of Chlorpyrifos and Phosalone in water samples using HPLC. J Sep Sci. 2010;33:1044–51.Pelit L, Dizdas TN. Preparation and application of a polythiophene solid-phase microextraction fiber for the determination of endocrine-disruptor pesticides in well waters. J Sep Sci. 2013;36:3234–41.Ibrahim WAW, Nodeh HR, Aboul-Enein HY, Sanagi MM. Magnetic solid phase extraction based on modified ferum oxides for enrichment, preconcentration and isolation of pesticides and selected pollutants. Crit Rev Anal Chem. 2015;45:270–87.Li XS, Zhu GT, Luo YB, Yuan BF, Feng YQ. Synthesis and applications of functionalized magnetic materials in sample preparation. Trends Anal Chem. 2013;45:233–47.Maddah B, Shamsi J. Extraction and preconcentration of trace amounts of diazinon and fenitrothion from environmental water by magnetite octadecylsilane nanoparticles. J Chromatogr A. 2012;1256:40–5.Xie J, Liu T, Song G, Hu Y, Deng C. Simultaneous analysis of organophosphorus pesticides in water by magnetic solid phase extraction coupled with GC-MS. Chromatographia. 2013;76:535–40.Heidari H, Razmi H. Multiresponse optimization of magnetic solid phase extraction based on carbon coated Fe3O4 nanoparticles using desirability function approach for the determination of the organophosphorus pesticides in aquatic samples by HPLC-UV. Talanta. 2012;99:13–21.Yan S, Qi TT, Chen DW, Li Z, Li XJ, Pan SY. Magnetic solid-phase extraction based on magnetite/reduced graphene oxide nanoparticles for determination of trace isocarbophos residues in different matrices. J Chromatogr A. 2014;1347:30–8.Tavakoli M, Hajimahmoodi M, Shemirani F. Trace level monitoring of pesticides in water samples using fatty acid coated magnetic nanoparticles prior to GC-MS. Anal Methods. 2014;6:2988–97.Tang Q, Wang X, Yu F, Qiao X, Xu Z. Simultaneous determination of ten organophosphorus pesticide residues in fruits by gas chromatography coupled with magnetic separation. J Sep Sci. 2014;27:820–7.Shen H, Zhu Y, Wen X, Zhuang Y. Preparation of Fe3O4-C18 nano-magnetic composite materials and their cleanup properties for organophosphorous pesticides. Anal Bioanal Chem. 2007;387:2227–37.Bagheri H, Zandi O, Aghakhani A. Magnetic nanoparticle-based micro-solid phase extraction and GC–MS determination of oxadiargyl in aqueous samples. Chromatographia. 2011;74:483–8.Moravcova D, Rantamaki AH, Dusa F, Wiedmer SK. Monoliths in capillary electrochromatography and capillary liquid chromatography in conjunction with mass spectrometry. Electrophoresis. 2016;37(7–8):880–912.Nema T, Chan ECY, Ho PC. Applications of monolithic materials for sample preparation. J Pharm Biomed Anal. 2014;87:130–41.Vergara-Barberán M, Lerma-García MJ, Simó-Alfonso EF, Herrero-Martínez JM. Solid-phase extraction based on ground methacrylate monolith modified with gold nanoparticles for isolation of proteins. Anal Chim Acta. 2016;917:37–43.Vukoje ID, Dzunuzovic ES, Vodnik VV, Dimitrijevic S, Ahrenkiel SP, Nedeljkovic JM. Synthesis, characterization, and antimicrobial activity of poly(GMA-co-EGDMA) polymer decorated with silver nanoparticles. J Mater Sci. 2014;49:6838–44.Krenkova J, Foret F. Iron oxide nanoparticle coating of organic polymer-based monolithic columns for phosphopeptide enrichment. J Sep Sci. 2011;34(16–17):2106–12.Daou TJ, Begin-Colin S, Grenèche JM, Thomas F, Derory A, Bernhardt P, et al. Phosphate adsorption properties of magnetite-based nanoparticles. Chem Mater. 2007;19:4494–505.Mezenner NY, Bensmaili A. Kinetics and thermodynamic study of phosphate adsorption on iron hydroxide-eggshell waste. Chem Eng J. 2009;147:87–96.Yang C, Wang G, Lu Z, Sun J, Zhuang J, Yang W. Effect of ultrasonic treatment on dispersibility of Fe3O4 nanoparticles and synthesis of multi-core Fe3O4/SiO2 core/shell nanoparticles. J Mater Chem. 2005;15:4252–7.Carrasco-Correa EJ, Ramis-Ramos G, Herrero-Martínez JM. Methacrylate monolithic columns functionalized with epinephrine for capillary electrochromatography applications. J Chromatogr A. 2013;1298:61–7.Waldron RD. Infrared spectra of ferrites. Phys Rev. 1955;99:1727–35.Yamaura M, Camilo RL, Sampaio LC, Macedo MA, Nakamura M, Toma HE. Preparation and characterization of (3-aminopropyl)triethoxysilane-coated magnetite nanoparticles. J Magn Magn Mat. 2004;279:210–7.Jiang L, Sun W, Kim J. Preparation and characterization of ω-functionalized polystyrene–magnetite nanocomposites. Mater Chem Phys. 2007;101:291–6.Dallas P, Georgakilas V, Niarchos D, Komninou P, Kehagias T, Petridis D. Synthesis, characterization and thermal properties of polymer/magnetite nanocomposites. Nanotechnology. 2006;17:2046–53.Zhao XL, Shi YL, Wang T, Cai YQ, Jiang GB. Preparation of silica-magnetite nanoparticle mixed hemimicelle sorbents for extraction of several typical phenolic compounds from environmental water samples. 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Química: prácticas de laboratorio

El objetivo de este texto es ofrecer un material completo que permita al lector comprender y desarrollar las técnicas más usuales en el laboratorio de Química. De esta manera, está especialmente indicado para el estudiante universitario de los primeros cursos de estudios científicos. Cada capítulo comienza con una introducción al marco teórico que se va a tratar, que desemboca en la resolución de un caso práctico en el laboratorio. Junto con ésto, al finalizar cada capítulo se plantea al lector una serie de cuestiones que le permiten constatar tanto si es capaz de extraer conclusiones a partir de los experimentos desarrollados, como si ha comprendido el porqué de los pasos seguidos.Torres Cartas, S.; Meseguer Lloret, S.; Catalá Icardo, M.; Gómez Benito, C. (2022). Química: prácticas de laboratorio. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/185922EDITORIA

Terminology and classification of miracle slimming diets: A narrative review and new proposals

Introduction: In the last years, confusing or misleading use of the term called miracle or magic diets, using to weight loss treatment, has increased, along with several classification of them. Objectives: The purpose of this narrative review is to discuss miracle slimming diets and proposal new term and new classification for these diets. Methods: A narrative review up to September 2021 was carried out in the PubMed, Google Scholar, and Web of Knowledge. Furthermore, this strategy was complemented with a comprehensive search of the 'grey' literature [7] based in four different searching strategies: i) grey literature databases, ii) customized Google search engines, iii) targeted websites, and iv) consultation with contact experts. Results: Our proposal is to use the new concept called hazardous slimming diets defined as diets that propose rapid weight loss (> 1 kg/week), to be performed effortlessly, without the super-vision of a medical/nutritional professional, excessive energy restrictions and/or exclusion from the di-et of food or nutrients for the body. Furthermore, the development of a new algorithm reflected as is possible to classify the diet as non-effective, hazardous and effective diet. Conclusions: Our review could help to classify and develop a new terminology about the miracle slimming diets focusing in the knowledge to guarantee the quality in the treatments for weight loss

El cuy: una curiosidad de la medicina tradicional andina

Se realizó una revisión bibliográfica sobre la soba y radiografía del cuy durante los meses de septiembre de 2017 hasta febrero de 2018 en el Policlínico Docente Reina del municipio Centro Habana, con el objetivo de describir una breve panorámica de esta curiosa particularidad de la medicina tradicional andina. Se consultaron bases de datos de sistemas como MEDLINE, IBEC, Scielo, Who, con la utilización de descriptores como cuy, medicina tradicional andina y saber ancestral. Los sistemas de salud y la medicina ancestral consideran en sus análisis aspectos históricos, científicos-tecnológicos, jurídicos y políticos en la convivencia milenaria de los pueblos andinos

COVID Obesity: A One-Year Narrative Review

On 11 March 2020, coronavirus disease 2019 (COVID-19) was declared a pandemic by the World Health Organization (WHO). This study focuses on a narrative review about the illness during the first year of the pandemic in relation to obesity. Databases were used to search studies published up to 8 December 2020. In total, 4430 articles and other scientific literature were found, and 24 articles were included in this one-year narrative review. The mean BMI value of severe COVID-19 patients ranged from 24.5 to 33.4 kg/m2, versus <18.5 to 24.3 kg/m2 for non-severe patients. Articles using the terms obesity or overweight without indicating the BMI value in these patients were common, but this is not useful, as the anthropometric parameters, when not defined by this index, are confusing due to the classification being different in the West compared to among Asian and Korean criteria-based adults. We proposed a new term, called COVID obesity, to define the importance of this anthropometric parameter, among others, in relation with this pandemic