Abstract: Biological assay systems often involve suspending magnetically attractable particles in a liquid, and later bringing down the particles from suspension and separating the formed pellet from the supernatant liquid. The invention provides magnetic systems for this purpose, shaped to form an annular or part-annular pellet close to the bottom of the vessel. The systems are suitable for automation.

Abstract: Biological assay systems often involve suspending magnetically attractable particles in a liquid, and later bringing down the particles from suspension and separating the formed pellet from the supernatant liquid. The invention provides magnetic systems for this purpose, shaped to form an annular or part-annular pellet close to the bottom of the vessel. The systems are suitable for automation.

Abstract: A method of sequencing a target nucleic acid using primer extension mass spectroscopy to generate an observed mass spectrum, on which base calling cycles are carried out using calibrated inter-peak mass difference values such that: each called base allows mass calculation for the base-called peak in the observed mass spectrum; this calculated mass is then used as a further calibration point for subsequent rounds of base calling. A reaction mixture of all four base-specific chain extension nucleotides and four chain termination nucleotide analogues. A method of performing mass spectroscopy, which method comprises subjecting molecular ions which have been chemically charged in a predetermined manner to time-of-flight or Fourier transform mass spectroscopy.