Learn More
This study is focused on the synthesis and characterization of hydroxy-apo-10'-carotenal/quantum dot (QD) conjugates aiming at the in vivo visualization of β-ionone, a carotenoid-derived volatile compound known for its important contribution to the flavor and aroma of many fruits, vegetables, and plants. The synthesis of nanoparticles bound to plant(More)
The development of substitutes for the human skin, e.g., artificial skin constructs (ASCs), is of particular importance for pharmaceutical and dermatologic research because they represent economical test samples for the validation of new drugs. In this regard, it is essential for the skin substitutes to be reliable models of the genuine skin, i.e., to have(More)
The use of two-color two-photon (2c2p) excitation easily extends the wavelength range of Ti:sapphire lasers to the UV, widening the scope of its applications especially in biological sciences. We report observation of 2c2p excitation fluorescence of p-terphenyl (PTP), 2-methyl-5-t-butyl-p-quaterphenyl (DMQ) and tryptophan upon excitation with 400 and 800 nm(More)
The cofactors NADH and NADPH, hereafter NAD(P)H [NAD(P)= nicotinamide adenine dinucleotide (phosphate)], belong to the principal endogenous indicators of energetic cellular metabolism. Since the metabolic activity of cells is given by the ratio between the concentrations of free and protein-bound NAD(P)H, the development of autofluorescence techniques which(More)
Fluorescence fluctuation experiments are performed in single-molecule detection regime if the fluorescence of at most one molecule is registered at a time. Although the significance of such experiments for investigations of complex nonergodic systems like those met in the biosciences has been stressed out by many scientists, the quantitative and accurate(More)
In this assay we used polystyrene-tube-attached rabbit antibodies against prostatic acid phosphatase (PAP) that had been purified to homogeneity from human prostate. The amount of immunoreactive acid phosphatase was determined directly by its enzymic activity in the solid-phase-bound immune complex. The detection limit was 0.05 U/L (0.13 microgram/L), the(More)
The detection of nitric oxide (NO) is of considerable medical interest. NO is involved in a multitude of mammal physiological processes, and various non-invasive concentration determination methods for NO have been developed during the last few years. Regarding time resolved metabolism behavior the quantitative determination of the (15)N(16)O-isotopologue(More)
Modified hydroxyethyl starch is photo-crosslinked in the presence of a green fluorescent protein (GFP) (mTagGFP) to obtain loaded hydrogels as model for a drug-delivery system. An important factor for the protein release is the crosslinking density since a dense network should lead to hindered diffusion. To obtain information on the rotational and(More)
The analysis of autofluorescence, often regarded as undesired noise during the imaging of biological samples, allows label free, unbiased detection of NAD(P)H and melanin in native samples. Because both the emission and absorption spectra of these fluorophores overlap and they can hence not be differentiated using emission filters or with different(More)
Two-color two-photon (2c2p) excitation fluorescence is used to monitor the enzymatic cleavage of bovine serum albumin (BSA) by subtilisin. Fluorescence is generated by irradiation with spatially and temporally overlapping femtosecond laser beams resulting in simultaneous absorption of an 800 and a 400 nm photon. Thereby, excitation of the fluorescent amino(More)