Methods of triggering activation of encapsulated signal-generating substances and apparatus utilising activated signal-generating substances

A method of performing a bioassay comprising activating 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, said activating comprising treating said capsules with heat and with an acid or a base catalysing solution, the combination of said heat and the pH of the catalysing solution being such as to hydrolyse said precursor to the form in which it is able to generate a detectable signal.

Apparatus for detecting a signal output from a bioassay device that uses capsules having on their outer surface affinity molecules for specific recognition of and binding to any target molecules in a sample to be assayed to enable formation of target-capsule complexes, the 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 apparatus comprising:

• a light source for illuminating a reaction zone where the capsules are activatable by treating said capsules with heat and with an acid- or a base-catalysing solution, the combination of said heat and the pH of the catalysing solution being such as to hydrolyse said precursor to the form in which it is able to generate a detectable signal, and
• a heating device for heating solution in the reaction zone to a temperature at which the signal precursor undergoes hydrolysis.

27-30. (canceled)