DNA analyzer

The ability to detect small genetic changes becomes more difficult as mass increases. There is further an upper mass range where analysis is impractical. For low-resolution instruments this limit is around a 100 mer. Thus the mass has to be minimized or a high-resolution instrument employed. Alternatively, the smaller the piece of DNA analyzed, the more it chemically resembles a primer or nucleotide monomer thus separation of the two during cleanup is difficult to do. If the primers and nucleotides are not removed, they can provide a massive background on MS analysis or inhibit ionization of the PCR product by preferential ionization. Thus for practical reasons it is extremely difficult to employ a PCR product below a 40 to 50mer for direct ESI MS or ESI MS-MS analysis. 

The main conclusions of Thiery et al. (1976) were the following (i) all eleven mammalian DNAs analyzed exhibited the three major components 1.697, 1.704 and 1.709 g/cm, first observed in the bovine genome similar components appeared in avian genomes and were, likewise, responsible for the trailing of the CsCl bands on the heavy, GC-rich, side (ii) the DNAs of reptiles, amphibians and fishes showed a much lower skewness to the heavy side of their CsCl bands (iii) essentially symmetrical bands in CsCl, neglecting satellite bands, were displayed by DNAs from three invertebrates (two echinoderms and Dro.sophila) and from three unicellular eukaryotes, S. cerevisiae, E. gracilis, T. pyriformis (see Table 3.2). 

The technique has revolutionized forensic science, as DNA can be amplified from just a few cells and then the DNA analyzed and identified. 

Kambara, H. and Takahashi, S., Multiple-sheathflow capillary array DNA analyzer. Nature, 361, 565, 1993. 

Figure 5.4 IR-MALDI mass spectrum of large DNA analyzed from glycerol as a matrix. The spectrum depicts single-stranded DNA molecules of length up to 1.4 kb generated from restriction-digested plasmid DNA purified by ethanol precipitation. The...

Figure 4. The emission spectra of four commonly used fluorescent dyes in automated DNA analyzers. Image courtesy of PE Applied Biosystems...

Birnstiel, Genes and spacers of cloned sea urchin histone DNA analyzed by sequencing. Cell, 14 655 (1978). 

Impedance Spectroscopy DNA Analyzer With Dual-Slope Multiplying ADCs, IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS, 6 (5) 468-478. 

Biological/Medical Applications in water,creatinine in body fluids,telmisartan quantifying aldehyde-functionalized (carbonyl compound) DNA analyzing microperoxidases (microperoxidase substrate) analyzing/detecting peroxidases (peroxidase substrate) ... 

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