Filtern
Dokumenttyp
- Zeitschriftenartikel (5) (entfernen)
Schlagworte
- Fluoreszenz (3)
- Farbstoffe (2)
- Amidothioharnstoff (1)
- Amidothiourea (1)
- Amino groups (1)
- Amino-Gruppen (1)
- BODIPY-Farbstoffe (1)
- Dyes (1)
- Fluor-Substitution (1)
- Fluorescence (1)
A highly fluorescent pH sensing membrane for the alkaline pH range incorporating a BODIPY dye
(2013)
A robust and re-usable dipstick-type fluorescent pH sensor for the alkaline pH range was developed by embedding a brightly fluorescent borondipyrromethene (BODIPY) dye bearing an acidic phenol moiety into a polyurethane matrix immobilized on a 3D epoxy-functionalized polymer support. The sensor strip has a dynamic working range of pH 10.0–13.1, i.e., operates in strongly basic media where pH glass electrodes can suffer from alkaline errors, and tolerates a high electrolyte background such as simulated seawater and sewage. This work describes the preparation of the sensing material and provides insight into the features that a hydrogel sensing membrane can bestow on an embedded pH-responsive dye by means of optical spectroscopic investigations.
Fluorinated Boron-Dipyrromethene (BODIPY) dyes: bright and versatile probes for surface analysis
(2013)
A family of bright boron-dipyrromethene-type fluorophores with a high number of fluorine atoms (F-BODIPYs) has been developed and characterized by X-ray crystallography and optical spectroscopy. The introduction of 3,5-bis(trifluoromethyl)phenyl and pentafluorophenyl moieties significantly enhances the photostability of such dyes, yielding for instance photostable near-infrared (NIR) fluorophores that show emission maxima>750 nm, when the BODIPY's π system is extended with two (dimethylamino)styryl and (dimethylamino)naphthastyryl moieties, or green-emitting BODIPYs with fluorescence quantum yields of unity. When equipped with a suitable group that selectively reacts for instance with amines, F-BODIPYs can be used as potent dual labels for the quantification of primary amino groups on surfaces by X-ray photoelectron spectroscopy (XPS) and fluorescence, two powerful yet complementary tools for the analysis of organic surface functional groups. The advantage of reactive F-BODIPYs is that they allow a fast and non-destructive mapping of the labelled supports with conventional fluorescence scanners and a subsequent quantification of selected areas of the same sample by the potentially traceable XPS technique. The performance is exemplarily shown here for the assessment of the amino group density on SiO2 supports, one of the most common reactive silica supports, in particular, for standard microarray applications.
The measurement of biologically relevant anions, such as fluoride, is an important task in analytical chemistry, in particular, for dental health and osteoporosis. Although a large number of fluoride probes are known, the applicability under relevant conditions is limited to a few examples. To improve this situation, BODIPY-amidothiourea dyes with varying hydrogen-bond donating strengths were developed, the most H-acidic of which (1 c) could detect F- from an inorganic source (NaF) in 50?% aqueous solution (DMSO/water 1:1, v/v) with 0.01 ppm sensitivity through selective fluorescence quenching by a photoinduced electron-transfer (PET) process. Use of the probe and a reference dye with a test-strip assay and a portable and rapidly recording lateral-flow fluorescence reader made determination of F- in neat aqueous solutions, such as spiked water samples and toothpaste extracts, possible in a self-referenced manner, achieving a detection limit of 0.2 ppm.
Die Bestimmung von biologisch relevanten Anionen wie Fluorid ist eine wichtige Aufgabe in der analytischen Chemie, insbesondere im Hinblick auf Zahnpflege und Osteoporose. Es gibt zwar eine große Zahl an Fluoridsonden, ihre Anwendbarkeit unter umweltrelevanten Bedingungen ist aber auf wenige Beispiele beschränkt. Um dieses Ziel zu erreichen, wurden BODIPY-Amidothioharnstoff-Farbstoffe mit unterschiedlicher Wasserstoffbrückendonorstärke entwickelt, wovon die H-azideste Verbindung (1 c) anorganisches F- (aus NaF) in DMSO/H2O (1:1, v/v) mit 0.01 ppm Empfindlichkeit durch Fluoreszenzlöschung über einen photoinduzierten Elektronentransfer nachweisen kann. Einbettung der Sonde und eines Referenzfarbstoffs in einen Teststreifen-Assay mit einem tragbaren 'Lateral-Flow'-Fluoreszenzlesegerät ermöglichte die Bestimmung von F- in wässrigen Lösungen wie versetzten Wasserproben und Zahncremeextrakten mit interner Referenzierung bis zu einer Nachweisgrenze von 0.2 ppm.
A novel synthetic strategy toward highly fluorinated BODIPY dyes with exceptional photostabilities relying on sustainable gold catalysis has been developed. A key to the tailored pyrrole precursors is the gold catalysis performed in ionic liquids as the reaction medium, allowing a facile recycling of the catalysts. The dyes prepared are well-matching with the spectral windows of popular rhodamine dyes and possess high brightness while showing a distinctly higher photostability than the rhodamines especially in aprotic solvents.