Publications by authors named "Maria K Salomon-Flores"
Optical sensing of L-dihydroxy-phenylalanine in water by a high-affinity molecular receptor involving cooperative binding of a metal coordination bond and boronate-diol.
Dalton Trans
October 2024
Article Synopsis
- The text discusses a novel fluorescent synthetic receptor, CuL1, designed to selectively recognize the neurotransmitter levodopa in water, which is significant for biological and analytical chemistry.
- CuL1 is a cationic Cu(II)-terpyridine complex featuring a fluorescent quinolinium and phenylboronic acid that exhibits a high affinity for levodopa while maintaining selectivity over other neurotransmitters like dopamine and epinephrine.
- The detection of levodopa with CuL1 is demonstrated through a visual sensing method using eosin Y dye, showcasing how the receptor effectively displaces the dye and allows for its efficient monitoring.
Article Synopsis
- - The study focuses on creating and analyzing a specific salt derived from a complex porphyrin compound combined with tri-fluoro-methane-sulfonate, through a chemical reaction involving multiple reagents in a controlled environment.
- - The resulting compound, noted for its deep red-brown color, underwent crystallization, revealing its structure through advanced methods like single-crystal X-ray diffraction. This structure includes unique features like a partially coordinated calcium ion and specific arrangements of pyridinium rings.
- - Key interactions in the crystal structure include cation-π interactions between the calcium ions and the phenyl rings, as well as hydrogen bonding between the tri-fluoro-methane-sulfonate anions and water molecules
Article Synopsis
- The study focuses on creating novel receptors using arylboronic acid-based complexes that can selectively recognize fructosyl amino acids like fructosyl valine (FV) and fructosyl glycyl histidine (FGH) in water, important for understanding glycated hemoglobin in humans.
- Three different cationic Zn-terpyridine complexes were synthesized, with one complex (3Zn) showing the highest acidity and a strong affinity for FV, indicated by significant optical changes when these compounds interact.
- The mechanism of interaction involves a cooperative recognition process and fluorescence quenching due to an electron transfer, with FGH also increasing emission intensity but exhibiting a weaker affinity compared to FV.
Article Synopsis
- A new dicationic diboronic acid structure was synthesized and tested as a fluorescent receptor specifically for sorbitol in water at pH 7.4.
- When sorbitol is added, it causes a significant increase in fluorescence, while other saccharides like fructose and glucose only produce minor changes.
- The study confirms that the receptor has a high affinity for sorbitol due to a specific binding mechanism, making it effective for selective saccharide recognition in biological contexts.
Article Synopsis
- Three new diboronic acid-substituted bisquinolinium salts were created and analyzed for their ability to detect monosaccharides and polyols in water, specifically at physiological pH levels.
- The receptors were primarily effective at recognizing glucose and fructose, showing significant fluorescence changes, while the responses to other sugars like arabinose and galactose were much weaker.
- The study suggests that the binding of glucose to the receptors occurs through a cooperative mechanism, making these fluorescent systems promising for glucose detection in lower concentrations.
Efficient fluorescent recognition of ATP/GTP by a water-soluble bisquinolinium pyridine-2,6-dicarboxamide compound. Crystal structures, spectroscopic studies and interaction mode with DNA.
RSC Adv
September 2022
Article Synopsis
- - A new compound called compound 1, made from pyridine-2,6-dicarboxamide with two -alkylquinolinium units, was synthesized and studied as a fluorescent sensor for nucleotides in water.
- - When nucleotides are added to compound 1, its blue fluorescence decreases, showing a particular preference for ATP and GTP, as opposed to other nucleotides, highlighting its selective binding.
- - The receptor has a strong affinity for ATP due to its structural characteristics and bonding interactions, and it can effectively bind to DNA, indicating its potential applications in biochemical research.
Article Synopsis
- Biological catecholamines like l-DOPA and dopamine are important for brain function and can indicate certain diseases, prompting the development of new sensors to detect them effectively.
- The study introduces fluorescent Zn(ii)-terpyridine complexes that selectively bind catecholamines and nucleosides, demonstrating a strong affinity for l-DOPA and showing significant changes in fluorescence when in the presence of these compounds.
- Advanced spectroscopic methods reveal the binding mechanism involves a unique interaction between the chemosensors and l-DOPA, allowing for a rapid fluorescent response and color change that can be observed without specialized equipment.
Guanosine triphosphate (GTP) is a key biomarker of multiple cellular processes and human diseases. The new fluorescent dinuclear complex [Zn(L)(S)][OTf], (asymmetric ligand, L = 5,8-Bis{[bis(2-pyridylmethyl)amino] methyl}quinoline, S = solvent, and OTf = triflate anion) was synthesized and studied in-depth as a chemosensor for nucleoside polyphosphates and inorganic anions in pure water. Additions at neutral pH of nucleoside triphosphates, guanosine diphosphate, guanosine monophosphate, and pyrophosphate (PPi) to quench its blue emission (λ = 410 nm) with a pronounced selectivity toward GTP over other anions, including adenosine triphosphate (ATP), uridine triphosphate (UTP), and cytidine triphosphate (CTP).
View Article and Find Full Text PDFThree Ni(ii)-POCOP pincer complexes [NiCl{CH-4-OH-2,6-(OPPh)}], 1; [NiCl{CH-4-OH-2,6-(OPtBu)}], 2 and [NiCl{CH-4-OH-2,6-(OPiPr)}], 3 were studied as bifunctional molecular sensors for inorganic anions and acetate. In CHCN, fluoride generates a bathochromic shift with a colorimetric change for 1-3 with a simultaneous fluorescence turn on, this optical effect is based on deprotonation of the para-hydroxy group of the POCOP ligand. On the other hand, in a neutral aqueous solution of 80 vol% CHCN, additions of cyanide produce a distinct change of color by forming very stable complexes with the nickel-based receptors 1-3 with log K in the range of 4.
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