Supramolecular Chemistry: New chemodosimeters and hybrid materials for the chromo-fluorogenic detection of anions and neutral molecules

Tesis por compendio[EN] Abstract The present PhD thesis entitled "Supramolecular Chemistry: New chemodosimeters and hybrid materials for the chromo-fluorogenic detection of anions and neutral molecules" is based on the application of supramolecular chemistry and material science principles for the development of optical chemosensors for anions and neutral molecules detection. The second chapter of this PhD thesis is devoted to the preparation of chemodosimeters for the chromo-fluorogenic detection of fluoride, diisopropyl fluorophosphates (DFP) and hydrogen sulfide. The optical detection of fluoride anion was achieved by using a pyridine derivative containing a t-butyldimethylsilyl ether group. Aqueous solutions of the chemodosimeter were colorless but turned yellow upon addition of fluoride anion. Also a remarkable enhancement in emission was observed only upon the addition of fluoride. The optical changes were ascribed to a fluoride-induced hydrolysis of the silyl ether moiety. Also a chemodosimeter for the optical recognition of DFP, a nerve agent simulant, was prepared. In this case, the chemodosimeter was based on a stilbene pyridinium derivative functionalized with hydroxyl and silyl ether moieties. Aqueous solutions of the chemodosimeter were colorless changing to yellow upon DFP addition. The optical changes were ascribed to a hydroxyl phosphorylation followed by a fluoride-induced hydrolysis of the silyl ether group. Besides, that probe was implemented in test strips and DFP detection in gas phase was accomplished. Finally, the fluorogenic recognition of hydrogen sulfide anion was explored. For this purpose different fluorophores were selected and fucntionalized with 2,4-dinitrophenyl ether groups. The prepared probes were neraly non-emissive but remarkable emission enhancements upon addition of hydrogen sulfide were observed. The emission enhancements observed were due to a selective sulfide-induced hydrolysis of the 2,4-dinitrophenyl ether moiety that yielded the free fluorophores. Another set of chemodosimeters equipped with azide and sulfonylazide moieties were prepared. Again these probes were non-fluorescent but upon addition of hydrogen sulfide an important enhancement in emission was found. The selective response was ascribed to a reduction of the azide and sulfonylazide moieties to amine and sulfonylamide induced by hydrogen sulfide anion. Besides, the viability assays showed that these dosimeters were essentially non-toxic and real-time fluorescence imaging measurements confirmed their ability to detect intracellular hydrogen sulfide at micromolar concentrations. The third chapter of this PhD thesis was devoted to the preparation of nanoscopic gated materials and their use in sensing protocols. In a first step a gated material for the optical detection of glutathione (GSH) was prepared. For this purpose MCM-41 mesoporous silca nanoparticles were selected as inorganic scaffold. The pores were loaded with safranine O and the external surface was functionalized with disulfide-containing oligo(ethylene glycol) moieties. Dye delivery from aqueous suspensions of the sensory material was only observed in the presence of GSH. The signalling paradigm was ascribed to the selective reduction of the disulfide bond by GSH which induced pore opening and dye release. Also capped organic-inorganic hybrid materials for the selective detection of hydrogen sulfide were prepared and characterized. In this case the same MCM-41 support was used and charged with [Ru(bipy)3]2+ dye. Then, the external surface was functionalized with Cu(II)-macorcyclic complexes and finally, the pores were capped by the addition of the bulky anion hexametaphosphate. Aqueous suspensions of this material showed negligible dye release whereas in the presence of hydrogen sulfide anion a remarkable colour change was observed. This optical response was ascribed to a demetallation process of the Cu(II) complex induced by hydrogen sulfide.[ES] Resumen La presente tesis doctoral titulada "Química supramolecular: Nuevos dosímetros químicos y materiales híbridos para la detección cromo-fluorogénica de aniones y moléculas neutras." está basada en la aplicación de principios básicos de la química supramolecular y de la ciencia de materiales en el desarrollo de sensores ópticos para aniones y moléculas neutras. El segundo capítulo de esta tesis doctoral está dedicado a la preparación de dosímetros químicos para la detección cromo-fluorogénica de fluoruro, diisopropil fluorofosfato (DFP) y sulfuro de hidrógeno. Para la detección óptica del anión fluoruro se sintetizó un derivado de piridina funcionalizado con un t-butildimetilsilil éter. En este capítulo también se describe la preparación de un dosímetro químico para la detección de DFP, que es un simulante de agentes nerviosos. Este dosímetro está basado en un estilbeno funcionalizado con una sal de piridinio que contiene grupos hidroxilo y silil éter en su estructura. Finalmente se prepararon dos familias de sensores para la detección óptica de hidrógeno sulfuro. La primera familia de sensores consiste en fluoróforos comunes funcionalizados con 2,4-dinitrofenil éteres. Los sensores preparados no presentaron una emisión de fluorescencia importante mientras que, en presencia del anión hidrógeno sulfuro, se observó un aumento significativo. La segunda familia de dosímetros también estaba compuesta por ciertos fluorofóros pero, en este caso, funcionalizados con grupos azida y sulfonilazida. Los dosimétros preparados, siguiendo esta segunda aproximación, tampoco dieron una fluorescencia significativa observándose un aumento de la misma al añadir el anión hidrógeno sulfuro. El tercer capítulo de esta tesis doctoral está dedicado a la preparación de materiales híbridos nanoscópicos funcionalizados con puertas moleculares y su aplicación en protocolos de reconocimiento. En primer lugar se preparó un material para la detección óptica de glutatión (GSH). Para ello se emplearon nanopartículas de MCM-41 mesoporosas como soporte inorgánico. Los poros del soporte fueron cargados con el colorante safranina O y la superficie externa funcionalizada con oligo(etilenglicol) conteniendo enlaces disulfuro. También se prepararon y caracterizaron varios materiales híbridos para la detección selectiva del anión hidrógeno sulfuro. En este caso también se empleó, como soporte inorgánico, sílice mesoporosa MCM-41. Los poros del soporte inorgánico fueron cargados con [Ru(bipy)3]2+ y la superficie externa funcionalizada con varios complejos macrocíclicos de Cu(II). El material sensor final fue obtenido al añadir el anion hexametafosfato, que compleja con los complejos de Cu(II), produciendo un bloqueo de los poros.[CA] Resum La present tesi doctoral titulada "Química supramolecular: Nous dosímetres químics i materials híbrids per a la detecció cromo-fluorogènica d'anions i molècules neutres." està basada en l'aplicació dels principis bàsics de la química supramolecular i de la ciència dels materials en el desenvolupament de sensors òptics per a anions i molècules neutres. El segon capítol d'aquesta tesi doctoral està dedicat a la preparació de dosímetres químics per a la detecció cromo-fluorogènica de fluorur, diisopropil fluorofosfat (DFP) i sulfur d'hidrogen. Per a la detecció òptica de l'anió fluorur es va sintetitzar un derivat de piridina funcionalitzat amb un t-dibutildimetilsilil èter. En aquest capítol també es descriu la preparació d'un dosímetre químic per a la detecció de DFP, que és un simulant d'agents nerviosos. Aquest dosímetre està basat en un estilbè funcionalitzat amb una sal de piridina que conté grups hidroxil i silis èter en la seua estructura. Finalment varen ser preparades dues famílies de sensors per a la detecció òptica de sulfur d'hidrogen. La primera família consisteix en fluoròfors comuns funcionalitzats amb 2,4-dinitrofenil èters. Els sensors preparats no presentaren una emissió de fluorescència significativa mentre que, en presencia de l'anió hidrogen sulfur, es va observar un augment significatiu. La segona família de dosímetres també estava composada per certs fluròfors però, en aquest cas, funcionalitzats amb grups azida i sulfonilazida. Els dosímetres preparats, seguint aquesta segona aproximació, tampoc donaren una fluorescència significativa observant-se un augment de la mateixa al afegir l'anió hidrogen sulfur. El tercer capítol d'aquesta tesi doctoral està dedicat a la preparació de materials híbrids nanoscòpics funcionalitzats amb portes moleculars i la seua aplicació en protocols de reconeixement. En primer lloc es va preparar un material per a la detecció òptica de glutatió (GSH). Per a aquest propòsit es varen emprar nanopartícules MCM-41 mesoporoses com a suport inorgànic. Els porus del suport varen ser carregats amb el colorant safranina O i la superfície externa funcionalitzada amb oligo(etilenglicol) que contenia enllaços disulfurs. També varen ser preparats i caracteritzats diversos materials híbrids per a la detecció selectiva de l'anió hidrogen sulfur. En aquest cas també es va emprar, com a suport inorgànic, sílice mesoporosa MCM-41. Els porus del suport inorgànic varen ser carregats amb [Ru(bipy)3]2+ i la superfície externa funcionalitzada amb diversos complexos macrocíclics de Cu(II). El material sensor final es va obtindre al afegir l'anió hexametafosfat, que es complexa amb macrocicles de Cu(II), produint un bloqueig dels porus.El Sayed Shehata Nasr, S. (2015). Supramolecular Chemistry: New chemodosimeters and hybrid materials for the chromo-fluorogenic detection of anions and neutral molecules [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/52598TESISCompendi

Hydrogel gratings with patterned analyte responsive dyes for spectroscopic sensing

This is an unprecedented report of hydrogel gratings with an analyte responsive dye immobilised in alternating strips where the patterned dye is its own dispersive element to perform spectroscopy. At each wavelength, the diffraction efficiency of hydrogel gratings is a function of dye absorbance, which in turn is dependent on the concentration of analytes in samples. Thus, changes in intensity of diffracted light of hydrogel gratings were measured for sensing of analytes. Equally, the ratio of diffracted intensities at two wavelengths was used for quantification of analytes to reduce errors caused by variations in intensity of light sources and photobleaching of dyes. 15.27 μm pitch gratings were fabricated by exposing 175 μm thick films of photofunctionalisable poly(acrylamide) hydrogel in a laser interferometric lithography setup, generating an array of alternating lines with and without free functional groups. The freed functional groups were reacted with pH sensitive fluorescein isothiocyanate to create gratings for measurement of pH. The ratio of intensity of diffracted light of hydrogel gratings at 430 and 475 nm was shown to be linear over 4 pH units, which compares favourably with ∼2 pH units for conventional absorption spectroscopy. This increased dynamic range was a result of cancellation of the opposite non-linearities in the pH response of the analyte responsive dye and the diffraction efficiency as a function of dye absorbance

Regioselective Green Synthesis and Antimicrobial properties of full fused non mixed Heterocyclic Systems

One pot synthesis and reaction of triazinthione and triazinohydrazide derivatives with different electrophilic reagents in ordered to synthesis of some interesting non-mixed heterocyclic compounds. Structures of thiazolotriazine, triazolotriazine, pyrimidinyltriazine, and triazinotriazine derivatives were established via spectroscopic data and elemental analysis. The synthesized compounds were screened for their antimicrobial activity

AMELIORATIVE EFFECT OF PHOENIX DACTYLIFERA ON ADVERSE EFFECTS OF LINEZOLID IN MALE ALBINO RATS

Objective: This study aimed to investigate the adverse effects of linezolid (LZD) on biochemical and hematological parameters and some organsincluding bone marrow, brain, and kidneys and to investigate the possibility of methanolic extract of Phoenix dactylifera (MEPD) to counteract theadverse effects of LZD.Methods: Forty-eight adult male albino rats were allocated into four equal groups (each of 12 animals). The first group received Tween 80 orally. Thesecond group received was given 0.5 ml of LZD suspension 4% in Tween 80 (100 mg/kg body weight) orally. The third group received the same doseof LZD suspension followed by 1 ml of MEPD orally. The rats in the last group were given 1 ml of MEPD (1000 mg/kg body weight) orally. Rats weresacrificed and blood samples were collected for hematological and biochemical study. Femur bones, brain, and kidneys were dissected and kept in ajar containing 10% formalin to perform the histopathological investigation.Results: The dose of LZD administered for 14 successive days induced a mild-to-moderate hematological abnormalities including decrease inhemoglobin content (7.88±0.18 g/L) on day-1 post-treatment. Significant increase in serum urea (59.75±0.85) and serum creatinine was observed(1.89±0.04). On day-14 post-treatment, LZD induced mild-to-moderate cellular abnormalities in bone marrow, brain, and kidneys. The concurrentoral administration of MEPD and LZD for the same period corrected the hematological, biochemical, and histopathological alterations induced by LZD. Conclusion: It was concluded that MEPD clearly ameliorated these damaging effects induced by LZD

Ultrasonic and solvent free Synthesis of Regioselective Diastereomeric Adducts and Heterocyclic Products as antibacterial agent

Oxirane ring containing the carboxylic group in the α,β-position are useful intermediates in the synthesis of biologically active compounds. Epoxidation of 4-(4-acetylamino and/or bromophenyl)-4-oxo-but-2-enoic acids via ultrasound condition afforded α-oxirane carboxylic acid followed by regioselective diastereomeric adducts of camphor. The steric factor plays an important role in regioselectivity. Formation of oxirane and furan derivatives via ultrasonic condition was considered as key steps for synthesis of some important heterocyclic compounds. The structure of new synthesized compounds 2-9a,b were elucidated by elemental analysis and spectroscopic data. The antibacterial activity for the synthesized compounds was evaluated

Metal-organic framework (MOF) dispersion based fluids for solar-thermal energy conversion

This paper discusses the potential use of metal–organic framework (MOF) dispersion based fluids for solar-to-thermal energy conversion (STEC). For this, the optical and thermal characteristics of MOF dispersion were investigated, with MOFs dispersed in ethylene glycol (EG). This study is focused on three different MOF dispersions, namely ZIF8/EG, CuBTC/EG, and FeBTC/EG, each with varying concentrations of MOF particles. The results showed that FeBTC/EG at a concentration of 0.3 wt% is the optimal fluid for STEC, exhibiting the highest absorption and STEC efficiency compared to the other two fluids. The study also highlights the trade-off between STEC efficiency and cost, as increasing the concentration of MOF particles decreases the specific absorption rate (SAR). Additionally, the paper evaluates the dispersion stability of FeBTC/EG over time, which is critical for practical STEC applications. The novelty of the paper lies in the use of MOF dispersion based fluids for STEC application, which has not been extensively studied before. This study provides valuable insights into the potential use of MOF/EG for STEC and highlights the importance of optimizing the concentration of MOF particles for efficient and cost-effective performance. This study also introduces the novel application of MOF dispersion based fluids for enhanced STEC performance, showcasing FeBTC/EG as a standout for its high efficiency and stability. It marks a significant stride in utilizing MOF materials for sustainable energy, emphasizing practical considerations of dispersion stability and cost-effectiveness in STEC systems.</p

Trends and Decomposition Growth Analysis of the Most Important Cereal Crops in Egypt

This research aims to analyze the growth performance of the most important cereal crops of Egypt agriculture (wheat, rice, and maize) and the sources of the production growth of these crops during the period 1975-2017. This analysis is to implement appropriate policies that would enhance the production increase of these crops using component analysis. Based on the results of the Chow Breakpoint test, the study was divided into three periods: 1975-1986, 1987-2000 and 2001-2017, in addition to the full period 1975-2017.The results showed that the growth of wheat, rice and maize production during the study periods depends on changes in yield more than changes in area. So, the study emphasizes that the vertical expansion has a greater impact than the horizontal expansion. This is reflecting the effect of scientific research and development (R&D) on increasing cereal crops in Egypt

Simple Endotoxin Detection Using Polymyxin-B-Gated Nanoparticles

"This is the peer reviewed version of the following article: Otri, Ismael, Sameh El-Sayed, Serena Medaglia, Ramón Martínez-Máñez, Elena Aznar, and Félix Sancenón. 2019. Simple Endotoxin Detection Using Polymyxin-B&-Gated Nanoparticles. Chemistry A European Journal 25 (15). Wiley: 3770 74. doi:10.1002/chem.201806306, which has been published in final form at https://doi.org/10.1002/chem.201806306. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving."[EN] A nanodevice based on mesoporous silica nanoparticles with rhodamine B in the pore framework, functionalized with carboxylates on the outer surface and capped with the cationic polymyxin B peptide, was used to selectively detect endotoxin in aqueous solutions with a limit of detection in the picomolar range.The authors thank the Spanish Government (MAT2015 64139-C4-1-R) and the Generalitat Valenciana (PROMETEO2018/024) for their support. I.O. thanks to Erasmus Mundus Programme, Action 2, Lot 1, Syria, for his predoctoral fellowship. S.S. is grateful to Spanish Ministerio de Economia y Competitividad for his Juan de la Cierva contract (FJCI-2015-27201).Otri, I.; El Sayed, S.; Medaglia, S.; Martínez-Máñez, R.; Aznar, E.; Sancenón Galarza, F. (2019). Simple Endotoxin Detection Using Polymyxin-B-Gated Nanoparticles. Chemistry - A European Journal. 25(15):3770-3774. https://doi.org/10.1002/chem.201806306S377037742515Ulevitch, R. J., & Tobias, P. S. (1994). Recognition of endotoxin by cells leading to transmembrane signaling. Current Opinion in Immunology, 6(1), 125-130. doi:10.1016/0952-7915(94)90043-4YOUNG, L. S. (1977). Gram-Negative Rod Bacteremia: Microbiologic, Immunologic, and Therapeutic Considerations. Annals of Internal Medicine, 86(4), 456. doi:10.7326/0003-4819-86-4-456Mueller, M., Lindner, B., Kusumoto, S., Fukase, K., Schromm, A. B., & Seydel, U. (2004). 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F., & Martínez-Máñez, R. (2016). Molecular gated nanoporous anodic alumina for the detection of cocaine. Scientific Reports, 6(1). doi:10.1038/srep38649Mondragón, L., Mas, N., Ferragud, V., de la Torre, C., Agostini, A., Martínez-Máñez, R., … Orzáez, M. (2014). Enzyme-Responsive Intracellular-Controlled Release Using Silica Mesoporous Nanoparticles Capped with ε-Poly-L-lysine. Chemistry - A European Journal, 20(18), 5271-5281. doi:10.1002/chem.201400148Wang, Y., Zhang, D., Liu, W., Zhang, X., Yu, S., Liu, T., … Wang, J. (2014). Facile colorimetric method for simple and rapid detection of endotoxin based on counterion-mediated gold nanorods aggregation. Biosensors and Bioelectronics, 55, 242-248. doi:10.1016/j.bios.2013.12.006Su, W., Cho, M., Nam, J.-D., Choe, W.-S., & Lee, Y. (2013). Aptamer-Assisted Gold Nanoparticles/PEDOT Platform for Ultrasensitive Detection of LPS. Electroanalysis, 25(2), 380-386. doi:10.1002/elan.20120045

Validity of sphenoid ostium in relation to posterior wall of maxillary sinus by computed tomography

Background: Sphenoid sinus is the most inaccessible paranasal sinus, enclosed within the sphenoid bone and intimately related to numerous vital neural and vascular structures. Anatomic variation of the sphenoid sinus is well documented and may complicate surgery in such a place.Objective: To assess the reliability of preoperative computed tomography (CT) in determination of the distance between the posterior wall of maxillary sinus (PWMS) and the sphenoid sinus ostium (SSO) in the coronal plane.Patients and methods: This was a prospective study of the distance between the SSO and the PWMS in the coronal plane, which was measured both radiologically in preoperative CT and intraoperatively during endoscopic sinus surgery for patients in need for middle meatal antrostomy and sphenoid sinusotomy at the same side. Distances obtained by both techniques have been tested for the degree of correlation. Number of the included patients was 25.Results: Forty four nasal sides were included in the study. The mean distance between the sphenoid sinus ostium and posterior wall of maxillary sinus in the coronal plane was 6.6 ± 1.8 mm when measured by preoperative CT and 6.9 ± 1.9 mm when measured directly during surgery. No significant difference was found between the mean distances measured by both techniques (p = 0.246) with good agreement between them (r = 0.864).Conclusion: Preoperative CT may be a reliable tool to preoperatively determine the difference in depth between the PWMS and the SSO