A new two-strip TLC method for the quality control of technetium-99m mercaptoacetyl-triglycine (Tc-MAG3).

Background: Tc-mercaptoacetyl-triglycine (Tc-MAG3) has been used for dynamic renal imaging since about 30 years. Free pertechnetate (TcO), colloidal Tc ((TcO)), Tc-tartrate (precursor), precomplexes (Tc-(MAG3)) and lipophilic Tc-MAG2 are the main radiochemical impurities that may occur in the preparation. The total amount of these impurities has to be identified before release of the product for patient administration to guarantee patient safety and good image quality.

Band offsets at semiconductor-oxide interfaces from hybrid density-functional calculations.

Band offsets at semiconductor-oxide interfaces are determined through a scheme based on hybrid density functionals, which incorporate a fraction alpha of Hartree-Fock exchange. For each bulk component, the fraction alpha is tuned to reproduce the experimental band gap, and the conduction and valence band edges are then located with respect to a reference level. The lineup of the bulk reference levels is determined through an interface calculation, and shown to be almost independent of the fraction alpha.