George R. Negrete

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Liposomes are important carriers for controlled drug release, for gene or antisense therapy, and for immunization. Radiolabeled liposomes can be used to evaluate the in vivo behavior of different liposome formulations, as well as for diagnostic imaging and radionuclide therapy. A novel method for radiolabeling liposomes with (99m)Tc-"SNS/S" complexes is(More)
Pharmacokinetic and organ distribution studies of liposomal drugs in humans are a challenge. A direct labeling method using (99m)Tc-N,N-bis(2-mercaptoethyl)-N',N'-diethyl-ethylenediamine (BMEDA) complex to label the commercially available pegylated liposomal doxorubicin, Doxil, has been introduced. Biodistributions of (99m)Tc-Doxil in normal rats were(More)
UNLABELLED Liposomes are important carriers for controlling the spatial and temporal distribution of drug molecules or other bioactive molecules. Radiolabeled liposomes have potential applications in diagnostic imaging and radionuclide therapy. The purpose of this study was to develop a practical method for labeling liposomes with therapeutic rhenium(More)
This paper describes a simple and inexpensive procedure to produce thin-films of poly(dimethylsiloxane). Such films were characterized by a variety of techniques (ellipsometry, nuclear magnetic resonance, atomic force microscopy, and goniometry) and used to investigate the adsorption kinetics of three model proteins (fibrinogen, collagen type-I, and bovine(More)
Pharmacokinetic and organ distribution studies of liposomal drugs in humans are a challenge. A direct labeling method using Tc-N,N-bis(2-mercaptoethyl)-N ,N -diethyl-ethylenediamine (BMEDA) complex to label the commercially available pegylated liposomal doxorubicin, Doxil, has been introduced. Biodistributions of Tc-Doxil in normal rats were performed to(More)
The fundamental photophysical properties of three symmetrically substituted 3,9-perylene analogues were examined in a diverse range of solvents. All three compounds exhibited solvent-dependent fluorescence quantum yield, which was lower than that of perylene or its diimides. Whilst the absence of a large excited state dipole moment suggests that there is no(More)
Alkylation of DNA by 7r,8t-dihydroxy,9t,10t-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (anti-BPDE) forms mainly trans adducts (with respect to the C-9/10 positions). We recently described a halide-catalyzed pathway that preferentially generates cis adducts and now report that the trans chlorohydrin of anti-BPDE (trans-BPDCH) is an intermediate in the(More)
A novel asparagine-derived lipid analogue (ALA(11,17)) bearing a tetrahydropyrimidinone headgroup and two fatty chains (11 and 17 indicate the lengths of linear alkyl groups) was synthesized in high yield and purity. The thin film hydration of formulations containing 5 mol % or greater ALA(11,17) in distearoylphosphatidylcholine (DSPC) generated(More)
A technique for carbohydrate analysis that is both inexpensive and easily performed is currently unavailable. In this communication we address the problem and have outlined a method for labeling saccharides with a visible dye, 4-amino-1,1'-azobenzene-3, 4'-disulfonic acid, which has an absorption maximum of 489 nm and an extinction coefficient of 37,615, to(More)
Perylene diimide derivatives have attracted initial interest as industrial dyes. Recently, much attention has been focused on their strong π-π stacks resulting from the large PDI aromatic core. These PDI stacks have distinct optical properties, and provide informative models that could mimic light-harvesting systems and initial charge transfer typical of(More)