65 u00b0 c the sa biotin bonds break because of this treatment and release fluorescently labeled reagents into solution the concentration of which can be determined spectro photometrically example 2 provides an example of the modification of molecular beacons suitable for use untethered in aqueous solution in order to make them compatible with tethering to b peg microgels much is already known about the design of molecular beacon probes for use in untethered assay applications these can be modified or new ones designed if necessary using established design techniques to render them compatible with a gel tethering approach similarly many primers which create amplicons specific to corresponding probes have been identified or can be designed using established methods and these too can be modified to render them compatible with a gel tethering approach the amplification primers are typically linear oligonucleotides they can be synthesized with biotin a spacer of oligo ethylene glycol e g sp9 and an oligonucleotide spacer of controllable length e g 10 t at their 5 u2032 end such molecules can be tethered to microgels via the sa b interaction table 1 summarizes molecular beacon probes nasba amplification primers and complementary targets and templates appropriate for simplex or multiplex assays of bloodstream infection according to.