OBJECTIVE This in vitro study was undertaken to evaluate the physical, chemical, and biological properties of commercially available metal orthodontic brackets in South Korea, because national standards for these products are lacking. METHODS FOUR BRACKET BRANDS WERE TESTED FOR DIMENSIONAL ACCURACY, (MANUFACTURING ERRORS IN ANGULATION AND TORQUE), CYTOTOXICITY, COMPOSITION, ELUTION, AND CORRO...

a mathematical model of sorption of zirconium and hafnium cations mixture and elution of these ions from a cation exchange resin bed is developed. sulfuric acid is selected as the eluent for selective separation of zr and hf in a packed bed of dowex cation exchange resin. the column model is a dispersed plug flow model,and assumed to consist of randomly packed synthetic and spherical resin bead...

A solid-phase extraction (SPE) method for sample clean-up and preconcentration followed by reversed-phase high-performance liquid chromatography (RP-HPLC) with uv detection is reported for determination of polycyclic aromatic hydrocarbons (PAHs) in the caspian seawater. A good resolution was obtained using acetonitrile:water (40:60) as mobile-phase for separation of these compounds. The eff...

Objective. This study aimed to evaluate triethylene glycol dimethacrylate (TEGDMA) elution from SDR bulk-fill composite. Methods. Three groups of samples were prepared, including samples polymerized in a 4 mm layer for 20 s, in a 4 mm layer for 40 s, and in a 2 mm layer for 20 s. Elution of TEGDMA into 100% ethanol, a 75% ethanol/water solution, and distilled water was studied. The TEGDMA conce...

Periprosthetic Joint Infection (PJI) is a challenging complication after joint replacements, and cement spacers are standard treatment in two-stage revision surgery. This experimental vitro study aimed to evaluate the elution properties of different gentamicin formulations from commercially available intraoperative molded hip spacers. The compared prepared with premixed antibiotic bone cement, ...

1. A systematic procedure for the purification of enzymes by affinity-elution chromatography is described. Enzymes are adsorbed on a cation-exchanger, and eluted with ligands specific for the enzyme concerned. 2. All of the glycolytic and some related enzymes present in rabbit muscle can be purified by the affinity-elution technique. The pH range for adsorption and elution of each enzyme was fo...

Neutral salts exhibit very marked differences as eluants of proteins from affinity columns. We observe: (i) that the relative potencies of neutral salts as eluants are independent of the protein or the affinity ligand in the systems studied, (ii) that the absolute salt concentration necessary to elute any given protein bound to the affinity matrix is proportional to the algebraic sum of a set o...

The rates of elution from RBC of the Lee and PR8 strains of influenza virus were studied by means of a step-wise elution technique. By means of a single treatment with lanthanum acetate or irradiation with ultraviolet and subsequent passage in chick embryos, it was possible to alter the elution rate of the Lee strain so that it was similar to that of the PR8 strain. This alteration proved to be...