Spatially Resolved Immobilization of Peptides by Electrochemical Polymerization after Photolytic Cleavage of a Protecting Group

Microstructuring of surfaces: Electrochemical polymerization after removal of a photolabile protecting group (nitrobenzyl group) represents a new method for spatially resolved immobilization of ligands or receptors. Thus, the electropolymerization of 3-hydroxyphenylacetyl peptides such as 1 on electrodes can be controlled by light     

FT-IR Mapping—A New Tool for Spatially Resolved Characterization of Polymer-Bound Combinatorial Compound Libraries with IR Microscopy

In the search for selective receptors , a promising approach is provided by immobilization of cyclopeptides on sensor surfaces (see picture) and subsequent detection of low molecular weight analytes with reflectometric interference spectroscopy (RIfS). Together with combinatorial chemistry, this innovative method offers a great potential for applications as sensors.     

Tl2CuAsO4 – ein Zwischenprodukt bei der Oxidation von Tl/Cu/As-Legierungen im Sauerstoffstrom

Tl₂CuAsO₄ – an Intermediate Phase in the Oxidation of Tl/Cu/As Alloys with Oxygen Waxy, honey-jellow single crystals of the new compound Tl₂CuAsO₄ (monoclinic, P2₁/c, a = 860.1(1) pm, b = 533.94(7) pm, c = 1200.1(2) pm, β = 98.10(1)°, Z = 4) were prepared as an intermediate product of the oxidation process in the reaction of Tl/Cu/As-alloys with oxygen. Their structure was determined from IPDS data (w2R = 0.071 for 1271 F² values and 74 parameters). The structure contains an isolated [Cu₂As₂O₈]^4– group consisting of two AsO₄-tetrahedra connected by two Cu⁺ ions with an approximately linear O–Cu–O coordination. The [Cu₂As₂O₈]^4– groups are linked to a threedimensional framework by thallium(I) ions which show an hemispheric coordination sphere of oxygen ions indicating the stereochemical activity of the Tl⁺ lone pair.     

Zn11Rh18B8 and Zn10MRh18B8 with M = Sc,Ti, V,Cr, Mn,Fe, Co,Ni, Cu,Al, Si,Ge, Sn – New Ternary and Quaternary Zinc Rhodium Borides

Zn₁₁Rh₁₈B₈ and Zn₁₀MRh₁₈B₈ with M = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Al, Si, Ge and Sn are obtained by reaction of the elemental components in sealed tantalum tubes at 1500 K. They crystallize tetragonally with Z = 2 in the spacegroup P4/mbm with lattice constants a = 1771.2(2) pm, c = 286.40(4) pm for Zn₁₁Rh₁₈B₈ and in the range a = 1767.65(9) pm, c = 285.96(3) pm (Zn₁₀NiRh₁₈B₈) to a = 1774.04(9) pm, c = 286.79(2) pm (Zn₁₀SnRh₁₈B₈) for the quaternary compounds. According to powder photographs all compounds are isotypic. Struture determinations based on single crystal X-ray data were performed with Zn₁₁Rh₁₈B₈, Zn₁₀FeRh₁₈B₈ and Zn₁₀NiRh₁₈B₈. The structure of Zn₁₁Rh₁₈B₈ is related to the Ti₃Co₅B₂ type. Along the short axis planar nets of rhodium atoms composed of triangles, squares, pentagons and elongated hexagons alternate with layers containing the boron and zinc atoms. The rhodium atoms form trigonal prisms centered by boron atoms, two kinds of tetragonal and pentagonal prisms centered by zinc atoms and elongated hexagonal prisms containing pairs of zinc atoms. In the quaternary compounds Zn₁₀MRh₁₈B₈ the zinc atoms in one sort of tetragonal prisms are replaced by M atoms.