Über das Thalliumheptagermanat Tl2Ge7O15

Zusammenfassung Im System Tl₂O–GeO₂ wird auf der GeO₂-reichen Seite neben den schon beschriebenen Verbindungen Tl₂Ge₄O₉, Tl₂Ge₅O₁₁ und Tl₂Ge₆O₁₃ ein weiteres Germanat, und zwar der Zusammensetzung Tl₂Ge₇O₁₅, aufgefunden. AusDK- undWeissenberg-Aufnahmen ergibt sich eine hexagonale Elementarzelle; die Gitterparameter betragen:a=12,67₃,c=7,46₀Å undc/a=0,589.     

Untersuchungen an Germanaten

Ohne Zusammenfassung     

Carbon nano-strings as reporters in lateral flow devices for DNA sensing by hybridization

Presently, there is a growing interest in the development of lateral flow devices for nucleic acid analysis that enable visual detection of the target sequence (analyte) while eliminating several steps required for pipetting, incubation, and washing out the excess of reactants. In this paper, we present, for the first time, lateral flow tests exploiting oligonucleotide-functionalized and antibody-functionalized carbon nanoparticles (carbon nano-strings, CBNS) as reporters that enable confirmation of the target DNA sequence by hybridization. The CBNS reporters were applied to (a) the detection of PCR products and (b) visual genotyping of single nucleotide polymorphisms in human genomic DNA. Biotinylated PCR product was hybridized with a dA-tailed probe. In one assay configuration, the hybrid is captured at the test zone of the strip by immobilized streptavidin and detected by (dT) ₃₀ -CBNS. In a second configuration, the hybrids are captured from immobilized (dA) strands and detected by antibiotin-CBNS. As low as 2.5 fmol of amplified DNA can be detected. For visual genotyping, allele-specific primers with a 5′ oligo(dA) segment are extended by DNA polymerase with a concomitant incorporation of biotin moieties. Extension products are detected either by (dT) ₃₀ -CBNS or by antibiotin-CBNS. Only three cycles of extension reaction are sufficient for detection. No purification of the PCR products or the extension product is required.