Synthesis of amphiphilic sulfonamide halogenated porphyrins: MALDI-TOFMS characterization and evaluation of 1-octanol/water partition coefficients

Porphyrins are key precursors for development of photosensitizers for photodynamic therapy. A new series of ortho-halogenated tetraarylporphyrins with sulfonamide substituents have been synthesized via chlorosulfonation reaction and characterized by MALDI-TOFMS. To predict their partition properties, log K_OW of a selected range of the synthesized halogenated amphiphilic porphyrins is described. A significant effect of the number and type of halogen group as well as on the number of sulfonamide side chain was observed. The determined 1-octanol/water partition coefficients showed that it is possible to obtain compounds with a wide range of lipophilicities, from log K_OW=−2.71 till log K_OW>4, which are suitable to optimize the biological efficacy of this class of sensitizers.     

The influence of aliphatic diols on the temperature of maximum density of water

The influence of various aliphatic diols on the temperature of maximum density (TMD) of water has been investigated. 1,2-Propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and 2,5-hexanediol were found to yield positive structural contributions to the solute-induced shift in the TMD, i.e., they are structure makers. Contrariwise, data from the literature indicate that 1,2-ethanediol is a structure breaker. Relationships between the structure making/breaking tendencies of the solutes and the relative positions of the two hydroxyl groups are discussed.     

Effect of nucleic acid contamination on partitioning of proteins in two-phase PEG-Dextran system

Downstream processing of bioproducts results in considerable losses of compounds of interest in a large number of cases. For the intracellular enzyme tartrate dehydrogenase, an analysis of the laboratory process for enzyme recovery revealed that maximum losses occur in the initial stages of purification when the enzyme is separated from nucleic acids and other undesirable enzymes. Hence, aqueous twophase extraction was studied to investigate the separation of several enzymes from nucleic acids. Single-component and binary equilibria for three commercially available enzymes (bovine serum albumin, trypsin, chymotrypsin) and yeast RNA were studied in a two-phase system consisting of dextran and polyethylene glycol (PEG). The effects of pH and concentrations of the components and salts (NaC1) were investigated.     

Factors affecting adsorption of organic solutes on cellulose acetate in an aqueous solution system

Summary The adsorption properties of esters, aldehydes, ethers and amides on cellulose acetate, which is commonly used as a reverse osmosis membrane material, in an aqueous solution system were measured by high-performance liquid chromatography. The adsorption property was characterized with the specific retention volume. For a noncyclic homologous series the logarithm of the specific retention volume was linearly correlated with the logarithm of the partition coefficient between 1-octanol and water. The fact that the slopes of these regression lines are almost identical confirms that the dominant effect on adsorption is the hydrophobic interaction between cellulose acetate and the solute molecule. The intercept represents the effect of the polar groups on adsorption. The effect of the polar group decreases as follows: C(O)O, CO, HCON > CH₃CON > OH, O.     

Activity coefficients and pitzer parameters in the systems Na+/Cs+/Cl-/TcO 4 - or ClO 4 - /H2O at 25°C

Isopiestic vapor pressure experiments are performed at 25°C with aqueous NaTcO₄, mixed NaTcO₄-NaCl, and NaCl reference solutions. The solubility of CsTcO₄ is determined in 0–7.4m CsCl and in 0–5.6m NaCl solutions. The osmotic coefficients of the binary and ternary solutions are used to evaluate the binary Pitzer parameters Β⁰, Β^l, and C^Φ for NaTcO₄ and the mixing parameters θ_{TcO 4} ^- /cl^- and ψ_Na ⁺/TcO ₄ ^- /cl^-. The binary Pitzer parameters for the sparingly soluble CsTcO₄ and CsC1O₄ are calculated together with ψ_Cs ⁺/mo ₄ ^- /cl^- from their solubilities in CsCl solution. The solubilities of CsTcO₄ in NaCl and CsClO₄ in NaClO₄ solution are also included in the parametrization of the reciprocal salt systems Na⁺/Cs⁺/Cl^-/MO ₄ ^- . The parameters Β⁰ and Β^l of pertechnetate and perchlorate salts correlate well with the ionic radii.     

Interfacial stability of compatibilizers dictated by the thermodynamic interactions in an immiscible system and the effects of micelles on the crystallization of PLLA

Poly(L-lactic acid) (PLLA) is blended with three acrylonitrile-butadiene-styrene (ABS) materials and compatibilized by a kind of poly(methyl methacrylate) (PMMA)-type reactive comb (RC) polymer (RC). The compatibilization efficiency is found to be dictated by the thermodynamic interactions between PMMA-type compatibilizers and ABS materials. For one type of ABS, which is composed of methyl methacrylate (MMA), styrene (St), acrylonitrile (AN), and butadiene (BD), the MMA component of ABS is able to strengthen the interaction between the PMMA-type compatibilizers and the ABS phase and thus the obtained compatibilized PLLA/ABS blends display a fine cocontinuous morphology and excellent mechanical properties. For the other two ABS materials, which are constituted by St, AN, and BD, it has been found that the PMMA-type compatibilizers are pulled out from the interface to form micelles in the PLLA phase, on account of the weakening interactions between ABS and PMMA-type compatibilizers. The thus formed micelles can interact with the crystallization of PLLA and the melting temperature (T_m) of PLLA is split into a lower and a higher peak firstly, compared to the T_m of neat PLLA, then significantly decrease to lower temperature, with increasing the amount of micelles in the PLLA phase. © 2020 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 372–382     

1,3-丙二醇制备研究进展

1,3丙二醇（1,3-PDO）是一种重要的化工原料,可以作为溶剂、抗冻剂、增塑剂、乳化剂、防腐剂、洗涤剂和润滑剂等[1],在食品、医药、化妆品和有机合成中有着重要应用.此外,1,3-PDO还可以作为聚酯、聚醚和聚氨酯的单体．     

Application of affinity partitioning in an aqueous two-phase system to the investigation of triazine dye enzyme interactions

Affinity partitioning in an aqueous two-phase system by using triazine dye-substituted polyethylene glycol and dextran was applied in the investigation of the affinity of kinases, dehydrogenases and aminotransferases to twelve triazine dyes. From the alteration of the partition coefficient (K) of the enzymes in the two-phase system in the presence or absence of dye-liganded polyethylene glycol, expressed as delta log K, quantitative data for the affinity of the enzymes to various triazine dyes were obtained. Optimal conditions for the purification of enzymes by applying dye-protein interaction were derived.     

Diffusion and partition coefficients of small organic solvents in molten miscible polymer blends: Correlations with thermodynamic interactions

The transport properties of small organic molecules in molten poly(vinyl chloride) (PVC)/atactic poly(methyl methacrylate) (PMMA) blends and their homopolymers were studied with inverse gas chromatography. The elution profiles resulting from various organic solvents and different experimental conditions were used for measuring diffusion and partition coefficients. With the van Deemter equation and retention volumes at infinite dilution, diffusion coefficients of 10^?7 to 10^?8 cm²/s and partition coefficients of 10–50 were calculated. The dependence of the diffusion and partition coefficients on experimental variables such as the blend concentration, temperature, and solute nature was examined. The presence of PMMA in PVC blends affected the sorption behavior of the PVC matrix up to a certain concentration. Beyond that, it was hard to derive any composition–diffusivity dependence. On the contrary, the diffusion and partition coefficients were greatly influenced by changes in the temperature and by the nature of the solute. For those solutes (e.g., chlorinated hydrocarbons) showing stronger interactions with polymer blends (higher negative values for the Flory–Huggins interaction parameter χ₁₍₂₃₎), higher diffusion and partition coefficients were obtained. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 267–279, 2004     

Solvent isotope effects on the solubility of argon and pair interactions in aqueous solution of hexamethylenetetramine

The solubilities of gaseous argon in solutions of hexamethylenetetramine (hmta) in H₂O and D₂O were measured at different concentrations, at five temperatures in the range of 283–318 K, and at a partial gas pressure of 101325 Pa by microvolumetry with an accuracy of ≤0.3%. The standard Setchenov coefficients for argon solutions and the thermodynamic parameters of Ar-hmta pairwise interactions were calculated from the data on the solubility. Interactions between hydrated Ar and hmta molecules are characterized by mutual repulsions. The structural states of water in the hydration sphere of hmta and in the bulk of solution are substantially different. Due to the difference in the mechanisms of hydration of hmta and Ar, the addition of the first component leads to a decrease in the solubility of the second component. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No 8, pp. 1389–1394, August, 2000.