Chromatography of plasmid DNA

Liquid chromatography plays a central role in process-scale manufacturing of therapeutic plasmid DNA (pDNA) for gene therapy and DNA vaccination. Apart from its use as a preparative purification step, it is also very useful as an analytical tool to monitor and control pDNA quality during processing and in final formulations. This paper gives an overview of the use of pDNA chromatography. The specificity of pDNA purification and the consequent limitations to the performance of chromatography are described. Strategies currently used to overcome those limitations, as well as other possible solutions are presented. Applications of the different types of chromatography to the purification of therapeutic pDNA are reviewed, and the main advantages and disadvantages behind each technique highlighted.     

Progress on phthalocyanine-conjugated Ag and Au nanoparticles: Synthesis,characterization, and photo-physicochemical properties

Phthalocyanine (Pc) complexes are an important class of dyes with numerous (e.g., biological, photophysical, and analytical) applications. Among the methods used to improve the properties of these complexes, one should mention the introduction of different substituents, variation of the central metal ion, ligand exchange, and conjugation to nanomaterials (e.g., carbon-based nanomaterials and metal nanoparticles (NPs)). This work briefly reviews Pc complex conjugation to Ag and Au NPs, highlights the different NP shapes, and discusses the diversity of conjugation approaches. Moreover, the use of UV–Vis spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, atomic force microscopy, dynamic light scattering and Fourier transform infrared spectroscopy to characterize Pc-NP hybrids is summarized. The effect of conjugation on Pc photo-physicochemical properties (fluorescence, singlet oxygen generation, triplet state formation, and optical limiting behavior) is discussed, and future perspectives for the synthesis and applications of new hybrids are provided.     

Photodynamic therapy based on organic small molecular fluorescent dyes

This review aims to provide a summary of the progress in organic small molecular fluorescent dyes for photodynamic therapy in recent years and it is classified according to the structures of dyes including cyanines, phthalocyanine, BODIPYs and other agents.     

LyP-1 peptide-functionalized gold nanoprisms for SERRS imaging and tumor growth suppressing by PTT induced-hyperthermia

The gold nanoprisms (GNPs) have exhibited special plasmonic properties for biomedical applications because of their unique shapes and dimensions. Based on their optical performance, the NIR dye IR780 not only enabled the GNPs-based nanosystem as SERRS nanoparticles for Raman-encoded molecular imaging, but also enhanced the plasmonic photothermal property by laser irradiation. Meanwhile, the GNPs/IR780-Lyp-1 by introduction of tumor-homing peptide segment LyP-1, which presents high affinity to p32 protein, demonstrated the increased enrichment in tumor region and enhanced photothermal therapy efficacy.     

Oxidation of ascorbic acid in the presence of phthalocyanine metal complexes. Chemical aspects of catalytic anticancer therapy. 1. Catalysis of oxidation by cobalt octacarboxyphthalocyanine

The kinetics of oxidation of ascorbic acid in the presence of cobalt octa-4,5-carboxyphthalocyanine sodium salt (Teraphthal) was studied. A kinetic equation was obtained and a scheme of the process was proposed. According to the scheme, the first stage is the formation of a complex of the catalyst with dioxygen, and the limiting stage is the reaction of dioxygen with the ascorbate monoanion. The influence of the pH of the medium and the presence of a transport protein (albumin) on the state and catalytic activity of Teraphthal was studied. The involvement of hydrogen peroxide and oxygen-centered radicals in the catalytic oxidation of ascorbic acid was proved.     

Polyethylenimine （PEI）-g-comb-poly（ethylene glycol）-transferrin（Ⅰ）： Tumor-targeted Vector for Gene Delivery In.vitro

The work described the synthesis and evaluation of PEI-g-comb-PEG-transferrin as a potential system for gene therapy in vitro. The MW of PEG was 10KDa, and PEI was 2KDa. Its structure was identified by NMR, FT-IR and TGA spectroscopy. MTT assay found that at concentration up to 4000 n mol/L of the polymer, cell viability was over 85%. The bio-character of polymer/DNA complex was characterized by agarose gel electrophoresis, ethidium bromide exclusion and zeta-potential assay. The polymer could retardate DNA at N/P ratio 3.0-3.5 （mol/mol）. The particle size of the polymer/DNA complex was less than 300 nm. Transfection efficiency of the complex was studied in COS7 and NT2 cell lines.     

Synthesis of porphyrin nitrogen mustards with potential anti-tumor activities in chemotheraphy and photodynamic therapy

2,7,12,18-Tetramethyl-13,17-di[3'-N,N'-di(2"-chloroethyl)aminopropyl]porphin and it's 3,8-di(1'-alkyloxyethyl)-analogous or porphyrin-nitrogen mustards were synthesized for the first time Their structures were determined by spectroscopics and elemental analyses.Most of the compounds possess both the chemotherapeutic and photodynamic effects on tumor and deserve further investigation.     

On the Chemistry of a Dibenzohypericin Derivative

Summary.  A hypericin derivative was synthesized in which instead of the methyl groups two benzene rings were condensed to the chromophoric system in order to extend its conjugation. This derivative showed lowered fluorescence and concomitantly enhanced sensitized production of active oxygen species as compared to hypericin. However, in contrast to intuition its long wavelength band remained unshifted in comparison to its parent compound hypericin. Geometry and absorption properties were also investigated by means of semiempirical calculations. Received July 27, 2001. Accepted August 9, 2001     

Syntheses and Properties of Two Heterocyclically Substituted Hypericin Derivatives: 10,11-Dibenzothiazolyl-10,11-didemethylhypericin and 10,11-Dibenzoxazolyl-10,11-didemethylhypericin

Summary. The syntheses of the two heterocyclically substituted title hypericin derivatives were achieved starting either from 6-benzothiazolyl-tri-O-methyl-6-demethylemodin or 6-benzoxazolyl-tri-O-methyl-6-demethylemodin. The use of microwave assisted synthesis for the preparation of these anthraquinone synthons and the chemical as well as photochemical properties of the corresponding unique hypericin derivatives, which might constitute new photodynamic therapy agents, are reported. The tautomeric and stereochemical aspects of these hypericin derivatives were investigated by means of semiempirical calculations (AM1).     

Electrochemical iodination of C-methyl derivatives of dodecahydro-7,8-dicarba-nido-undecaborate anion

By electrochemical iodination of potassium 7-methyl-7,8-dicarba-nido-undecaborate and potassium 7,8-dimethyl-7,8-dicarba-nido-undecaborate, their monoiodine derivatives (extracted as tetramethylammonium salts) are synthesized. Their structure is confirmed by NMR and IR spectra and also by elemental analysis data.