Strategies for antidepressants extraction from biological specimens using nanomaterials for analytical purposes: A review

Accurate and precise monitoring of antidepressant drugs represents a crucial step for the adequate and personalized treatment of several psychological disorders such as depression, which nowadays represent a social, economic and health major concern. Several chemical, electrochemical, and biological methods have been traditionally developed for the extraction and detection of antidepressants, even though several restrictions such as post-treatment required, elevate costs and limited efficiency. Nanotechnology is a field with a tremendous growth observed in the last two decades, especially regarding their many biological applications, such as antibacterial or as biosensors, as well as in many different applications related to medicine. Lately, nanotechnology has emerged as a promising substitute for the extraction of antidepressants instead of traditional techniques, as nanomaterials can be efficiently used as sorbents due to their small size and their high specific surface area which enhance their high reactivity. In this review article, we provide a general overview on the use of different nanomaterials for the extraction of antidepressants from biological specimens and discuss not only the advantages but also the major limitations of using such nanomaterials. Potential alternatives to overcome these drawbacks are discussed as well

Copper selenide film electrodes prepared by combined electrochemical/chemical bath depositions with high photo-electrochemical conversion efficiency and stability

Copper selenide (of the type Cu2-xSe) film electrodes, prepared by combined electrochemical (ECD) followed by chemical bath deposition (CBD), may yield high photo-electrochemical (PEC) conversion efficiency (~14.6%) with no further treatment. The new ECD/CBD-copper selenide film electrodes show enhanced PEC characteristics and exhibit high stability under PEC conditions, compared to the ECD or the CBD films deposited separately. The electrodes combine the advantages of both ECD-copper selenide electrodes (in terms of good adherence to FTO surface and high surface uniformity) and CBD-copper selenide electrodes (suitable film thickness). Effect of annealing temperature, on the ECD/CBD film electrode composition and efficiency, is discussed.The results of this work are partly based on K. Murtada M.Sc. Thesis, under direct supervision of H.S. Hilal. Other experimental measurements and calculations, including dark current experiments, film thickness measurement, electrical conductivity, SEM analysis, XRD &AFM analysis revisions were performed by A. Zyoud after the thesis completion. Additional film electrode stability experiments under PEC conditions, were also performed by A. Zyoud after the Thesis completion. SEM micrographs and EDX spectra were measured by T.W. Kim and H-J.C. at the KIER, Korea. The XRD patterns were measured by D-H. Park and H. Kwon at PUK. M.H.S. Helal and H. Bsharat contributed with literature search, discussions and modeling. M. Faroun measured AFM micrographs at Al-Quds University. H.S. Hilal acknowledges financial support from ANU, Islamic Development Bank, Al-Maqdisi Project and Union of Arab Universities. T.W. Kim and H-J. Choi acknowledge financial support from the framework of the Research and Development Program of the Korea Institute of Energy Research (B6-2523)

Empleo de nuevos (NANO) materiales para el desarrollo de metodologías analíticas en los campos alimentarios, farmacéuticos y bioanalíticos

En esta tesis doctoral, se presentan nuevas metodologías analíticas basadas en materiales nanométricos y no nanométricos. Uno de los objetivos principales es la potencial ganancia en sensibilidad y selectividad que se puede obtener al emplear las técnicas propuestas. En la primera parte de esta tesis, se presenta una nueva metodología basada en un compuesto de poli(estireno-co-divinilbenceno) de nanotubos de carbono magnéticos de pared múltiple. Este compuesto se usó como un material sorbente para extraer varios tipos de antidepresivos en orina humana y su separación mediante electroforesis capilar. El mismo sorbente magnético se usó para la extracción de cinco tipos de catecolaminas en la orina y el parche ventral oscuro del venado rojo macho Ibérico y la separación mediante cromatografía líquida-espectrometría de masas. Por otro lado, se presenta un método simple basado en la mancha de vidrio recubierta con poli(estireno-co-divinilbenceno). Esta metodología se basa en el uso de manchas de sangre de vidrio recubierto de poli(estireno-co-divinilbenceno) fabricadas en el laboratorio para la extracción de siete tipos de antidepresivos y su posterior separación/detección mediante cromatografía líquida capilar-espectrometría de masas. En la segunda parte de esta Tesis, se han desarrollado diferentes métodos para mejorar la sensibilidad del análisis electroquímico. Se presenta un método para el análisis de vainillina a partir de muestras de alimentos, utilizando nanopartículas de óxido de titanio dopadas con aluminio. Los nanomateriales preparados se utilizaron para modificar electrodos de carbono serigrafiados. Otro modelo se basa en la modificación electrodos de carbono serigrafiado con nanopartículas de seleniuro de cobre dopados con aluminio para la detección electroquímica de tirosina en muestras farmacéuticas. Finalmente, se presenta un nuevo enfoque para la síntesis de seleniuro de cobre-óxido de grafeno y su reducción mediante el empleo de dióxido de carbono supercrítico. El material decorado se usó para modificar el electrodo de carbono vítreo y la detección electroquímica de eugenol en varias muestras (clavo, canela y pasta dental)

LC-MS determination of catecholamines and related metabolites in red deer urine and hair extracted using magnetic multi-walled carbon nanotube poly(styrene-co-divinylbenzene) composite

A novel analytical methodology for the extraction and determination of catecholamines (dopamine, epinephrine and norepinephrine) and their metabolites DL-3,4-dihydroxyphenyl glycol and DL-3,4-dihydroxymandelic acid by LC-MS is developed and validated for its application to human and animal urine and hair samples. The method is based on the preliminary extraction of the analytes by a magnetic multi-walled carbon nanotube poly(styrene-co-divinylbenzene) composite. This is followed by a 90%. Accuracy values comprised the range 79.5–109.5% when the analytes were extracted from deer urine samples using the selected MMWCNT-poly(STY-DVB) sorbent. This methodology was applied to real red deer urine and hair samples, and concentrations within range from 0.05 to 0.5 µg mL−1 for norepinephrine and from 1.0to 44.5 µg mL−1 for its metabolite 3,4-dihydroxyphenyl glycol were calculated. Analyses of red deer hair resulted in high amounts of 3,4-dihydroxyphenyl glycol (0.9–266.9 µg mL−1