Search results for "Fluorophores"
showing 7 items of 7 documents
Electronic and Functional Scope of Boronic Acid Derived Salicylidenehydrazone (BASHY) Complexes as Fluorescent Dyes
2017
[EN] A series of boronic acid derived salicylidenehydrazone (BASHY) complexes was prepared and photophysically characterized. The dye platform can be modified by (a) electronic tuning along the cyanine-type axis via modification of the donor-acceptor pair and (b) functional tuning via the boronic acid residue. On the one hand, approach (a) allows the control of photophysical parameters such as Stokes shift, emission color, and two-photon absorption (2PA) cross section. The resulting dyes show emission light-up behavior in nonpolar media and are characterized by high fluorescence quantum yields (ca. 0.5-0.7) and brightness (ca. 35000-40000 M-1 cm(-1)). Moreover, the 2PA cross sections reach …
Strong Emission Enhancement in pH-Responsive 2:2 Cucurbit[8]uril Complexes
2019
Organic fluorophores, particularly stimuli-responsive molecules, are very interesting for biological and material sciences applications, but frequently limited by aggregation- and rotation-caused photoluminescence quenching. A series of easily accessible bipyridinium fluorophores, whose emission is quenched by a twisted intramolecular charge-transfer (TICT) mechanism, is reported. Encapsulation in a cucurbit[7]uril host gave a 1:1 complex exhibiting a moderate emission increase due to destabilization of the TICT state inside the apolar cucurbituril cavity. A much stronger fluorescence enhancement is observed in 2:2 complexes with the larger cucurbit[8]uril, which is caused by additional con…
Organic-Inorganic Hybrid Mesoporous Materials as Regenerable Sensing Systems for the Recognition of Nitroaromatic Explosives
2013
[EN] Fluorescent organic-inorganic mesoporous hybrid materials have been prepared and characterised, and their behaviour against nitroaromatic explosives have been tested. MCM-41 silica was used as an inorganic scaffold and pyrene (P derivative containing trialkoxysilane moieties), dansyl and fluorescein (D and F derivatives also containing trialkoxysilane groups, respectively) fluorophores have been anchored on hybrid materials by a co-condensation method to obtain a homogenous distribution of dyes into the pores of the support. Six sensing materials have been prepared, of which SP, SD, SF were hydrophilic and SPh, SDh, SFh were hydrophobic. Template-free hydrophilic materials (SP, SD, SF)…
Préparation de liposomes fonctionnels pour l’encapsulation de composés bioactifs ou de sondes moléculaires fluorescentes pour l’imagerie cellulaire
2016
At ICMUB Institute, SUV liposomes have been used to achieve fluorophore encapsulation (subphtalocyanine) for cellular imaging [1] and have been bioconjugated to a peptide (bombesin) to achieve site-specificity, thanks to the structural modification of cholesterol, a component of the liposome, upon introduction of a reactive function. Hence, such liposomes fonctionnalised on the outer face may react with the terminal function of the peptide. Upon purification of the liposome by FPLC a 15 % encapsulation rate was measured by UV/Vis and attempted by ICP. The (outer) diameter of the liposomes (dDLS and dMET) ranged between 20 and 60 nm depending on the type of function or substituents on the ou…
A new method for fluoride determination by using fluorophores and dyes anchored onto MCM-41
2002
A new colourimetric and fluorimetric method for fluoride determination in aqueous samples based on the specific reaction between fluoride and silica has been developed and applied on real samples. Descalzo Lopez, Ana Belen, adeslo@alumni.uv.es ; El Haskouri, Jamal, Jamal.Haskouri@uv.es ; Beltran Porter, Daniel, Daniel.Beltran@uv.es ; Amoros del Toro, Pedro Jose, Pedro.Amoros@uv.es
Multispectral autoflourescence detection of skin neoplasia using steady-state techniques
2019
In the current study were used excitation-emission matrices (EEMs) and synchronous fluorescence spectroscopy (SFS) steady-state techniques in a broad spectral regions (excitation at 220-500 nm and emission at 280-850 nm) to achieve the whole set of endogenous fluorophores, existed in normal and neoplastic cutaneous tissues. Several types of benign, dysplastic and malignant types of skin lesions were investigated ex vivo using both EEM and SFS modalities, namely the basal cell papilloma and carcinoma, pigmented nevi, dysplastic nevi, squamous cell carcinoma and malignant melanoma. Histological analysis was used as a “gold standard” for evaluation of clinical diagnosis of the lesions investig…
BODIPY atropisomer interconversion, face discrimination, and superstructure appending
2016
International audience; A strategy was developed to append sterically hindered apical pickets on both faces of the BODIPY platform to prevent stacking and aggregation. Ortho-substitution of both the meso-phenyl ring and the boron-bound catechol affords the right directionality to append pickets, achieve face discrimination, featuring two inter-convertible atropisomers, and is reminiscent of the picket-fence strategy in porphyrins.