Patent ID: 8586387

Claim:
A method of controlling the onset of signal generation in a bioassay using capsules containing a signal precursor that is hydrolysable from a latent form in which substantially no signal is generated to a form in which it is able to generate a detectable signal, the method comprising: (i) treating the capsules with a solution whose temperature is such that substantially no hydrolysis of the signal precursor takes place and whose pH is balanced such that either: (a) the pH is too high for the signal precursor to undergo significant acid-catalysed hydrolysis at ambient temperature but at which the signal precursor undergoes significant hydrolysis at elevated temperature; or: (b) the pH is too low for the signal precursor to undergo significant base-catalysed hydrolysis at ambient temperature but at which the signal precursor undergoes significant hydrolysis at elevated temperature; and (ii) subsequently heating the capsules in the treatment solution to initiate onset of hydrolysis of the signal precursor to the form in which it is able to generate a detectable signal.