Hydrophilic fluorescent dyes

In 2000, the first example of ELP diblock copolymers for reversible stimulus-responsive self-assembly of nanoparticles was reported and their potential use in controlled delivery and release was suggested [87]. Later, these type of diblock copolypeptides were also covalently crossUnked through disulfide bond formation after self-assembly into micellar nanoparticles. In addition, the encapsulation of l-anilinonaphthalene-8-sulfonic acid, a hydrophobic fluorescent dye that fluoresces in hydrophobic enviromnent, was used to investigate the capacity of the micelle for hydrophobic drugs [88]. Fujita et al. replaced the hydrophilic ELP block by a polyaspartic acid chain (D ). They created a set of block copolymers with varying... 

Hydrophobic (10a) and hydrophilic (10b) squaraines show a noticeable increase in fluorescence intensity in presence of HSA and importantly dye 10b, containing a sulfo group, exhibits a large intensity increase when bound to avidin, a protein well-known to quench many fluorescent dyes [58]. 

Fluorescent silica nanoparticles, called FloDots, were created by Yao et al. (2006) by two synthetic routes. Hydrophilic particles were produced using a reverse micro-emulsion process, wherein detergent micelles formed in a water-in-oil system form discrete nanodroplets in which the silica particles are formed. The addition of water-soluble fluorescent dyes resulted in the entrapment of dye molecules in the silica nanoparticle. In an alternative method, dye molecules were entrapped in silica using the Stober process, which typically results in hydrophobic particles. Either process resulted in luminescent particles that then can be surface modified with... 

Although FITC and other reactive fluorescein derivatives still are widely used to label (strept)avidin and other proteins, better fluorescence yield and stability will be obtained if one of the newer hydrophilic fluorescein dyes is used. See Chapter 9, Section 1, for additional details on labeling proteins with fluorescein. 

Encapsulation efficiency is commonly measured by encapsulating a hydrophilic marker (i.e. radioactive sugar, ion, fluorescent dye), sometimes using single-molecule detection. The techniques used for... 

Calcein is a stable, hydrophilic, highly fluorescent dye to which lipid membranes are essentially impermeable. It has been used as traceable stand-in for hydrophilic drugs in a variety liposomal drug delivery experiments. 

The fluorescence properties of Peptide 1 and Ip was investigated. Energy transfer from EDANS to dabcyl, quenching by dabcyl, was reduced by phosphorylation of Ser (Fig. 2). Peptide main chain was stretched by increase in hydrophilicity, and the distance between the fluorescence dye and quencher increased. 

Recent advances in detecting renal function include the development of fluorescently labeled novel compounds (hydrophilic pyrazine dyes, carbostyril 124-DTPA-Eu, fluorescein-labeled poly-D-lysine) and their detection via in vivo fluorescence imaging or through transcutaneous detection (Dorshow et al., 1998 Rabito et al., 2005 Rajagopalan et al, 2011 Poreddy et al, 2012). Both the hydrophilic pyrazine dyes (see Fig. 34.1) and the modified DTPA are cleared exclusively by glomerular filiation, and... 

Hydrophilic pyrazine dyes as exogenous fluorescent tracer agents for real-time point-of-care measurement of glo-memlar filtration rate. Journal of Medicinal Chemistry 54 5048-5058. 

Trypan blue solution 93595 Fluka Xex 488 nm kern 675 nm Trypan blue is a blue acid dye that contains two azo chromophores. It is a large, hydrophilic, tetrasulfonated dye. Trypan blue solution may be used in trypan blue-based cytotoxitiy and prohferation assays. It is a vital stain that is not absorbed by healthy viable cells. When cells are damaged or dead, trypan blue can enter the cell, allowing dead cells to be counted. When trypan blue binds to proteins the resulting complex emits red fluorescence. The method is sometimes referred to as the dye exclusion method. 

Cutinase Fusarium solani Fabric UV and fluorescence spectroscopy, dye assay, water absorption tests Hydrolysis, increased hydrophilicity, improved dye uptake [3, 6, 38, 82, 84, 85, 98]... 

Fig. 4 F88 micelles in the absence (left) and presence (right) of the surfactant CTAC (filled circles). The green symbols represent the fluorescence dye. In pure F88 micelles the dye is located in the outer hydrophilic and water-swoUen corona. When the surfactant is added, the electrostatic attraction between the dye C343 and the positively charged CTAC headgroups drags the dye inside the mixed micelles...

A further problem is that most of the best candidates are, as one may expect, strongly hydrophilic. As usual in biochemistiy, the addition of some dimethyl sulfoxide overcomes this limitation, but specific media have also been developed. Good results have been obtained with block polyesters polyamides that form micelles shown to be efficient nanocarriers for typical two-photon absorbing fluorescent dyes (see compounds 19-21 in Scheme 9.9) [30-32]. 

A novel approach for ion sensing is based on the use of potential-sensitive or polarity-sensitive dyes (PSDs) and was presented first106 in 1987. PSDs are charge dyes and typically located at the interface between a lipophilic sensor phase and a hydrophilic sample phase. The transport of an ion into the lipophilic sensor layer causes the PSD to be displaced from the hydrophilic/hydrophobic interface into the interior of the respective phase (or vice versa), thereby undergoing a significant change in its fluorescence properties107 110. 

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