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This paper describes a method for the selective removal of DNA from various cellular products using columns packed with polycation-immobilized cellulose beads. Polyethyleneimine (PEI), poly-N,N-dimethylaminopropylacrylamide (poly(DAPA)) and poly(1-lysine) (P1L), all of which have cationic properties, were used as the ligands on the beads. Cellufine-GC15 w and -CPC w were used as cellulose matrices. Adsorption of DNA by the beads was determined using a batchwise method or a column method. Each bead type showed high DNA adsorbing activity at pH 7.0 and ionic strengths of m ¼ 0.05 -0.8. The larger the pore size of the beads, the larger the DNA-adsorbing activity. The DNA adsorbing capacities per wet mL of PEI-, poly(DAPA)-and P1L immobilized Cellufine-CPC with large pore sizes, were 3.7, 3.2, and 1.8 mg, respectively. When a protein, such as bovine serum albumin (BSA) or g-globulin, was present in solution with the DNA under physiological conditions (pH 7.0, m ¼ 0.2), the DNA selectivity of the PEI immobilized Cellufine-CPC columns was unsatisfactory, because both the DNA and the protein were adsorbed into the column. In contrast, the poly(DAPA) immobilized Cellufine-CPC column selectively removed DNA from each protein solution contaminated with DNA under similar conditions: the DNA concentration in each treated protein solution was below 10 ng mL 21 , and high recovery of each protein (.92%) was obtained.

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In this work we have measured the dependence of terahertz emission via optical rectification from the 4-N,N-dimethylamino-4′-N′-methyl-stilbazolium tosylate crystal as a function of incident light polarization. Many structures, which varied depending on the polarization of the incident pulse, were observed in the frequency spectra. The observed structures can be explained by incorporating the refractive index dispersion, the response function, and the birefringence properties of the crystal into the mathematical model used to reconstruct the experimental data. Our results show that careful attention must be paid to these three properties when enhancing nonlinear susceptibility during the fabrication of efficient terahertz emitters.

ChemInform Abstract Irradiation of 1,2-diphenylcyclobutene (II), obtained by treatment of 1,2-dibenzoylethane (I) with titanium tetrachloride and zinc powder, leads to the formation of the tetraphenyltricyclo(4.2.0.0)octane (III). This is isomerized to form the tetraphenyl-1,5-cyclooctadiene (IV) and the tetraphenyltricyclo(3.3.0.0)octane (V) via a cation radical reaction upon photolysis in the presence of 9,10-dicyanoanthracene (DCA) as the photosensitizer. The compound (V) is also obtained by irradiation of (IV) in the presence of DCA. (Mechanism).