Sandwich assays paramagnetic beads

Several of the previously described methods are readily adapted for the purification of specific mRNAs. Most convenient is the system based on the use of paramagnetic beads (Table 3.16) in which the oligo(dT) should be replaced by specific oligomers. Alternatively, the (reverse) capture or sandwich assays described in Section 8.3 are well suited for hybrid selection. 

Fig. 9. Typical differential pulse voltammogram (DPV) for the oxidation signals of Au during the sandwich assay to 38pmol of CF-T (A) and sandwich assay without CF-T used as control (B). Conditions hybridization time, 15 min hybridization temperature, 42°C amount of paramagnetic beads, 50gg electrooxidation potential, +1.25V electrooxidation time, 120s DPV scan from +1.25 to OV, step potential 10 mV, modulation amplitude 50 mV, scan rate 33.5 mV/s, nonstirred solution.

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