| abstract |
Candidates for biological activity are screened in capsules, each capsule containing a candidate, a target (which may be a molecular species or a biological cell or multiple copies of such a species or cell), and an intelligent substance. The target is one with which a successful candidate will interact to evoke a particular response in the target, and the intelligent substance is one that undergoes a transformation as a result of the response, the transformation being detectable by observation of the capsule itself. The candidate and the target are isolated from each other in the capsule until a designated point in time thereby enabling the operator to control the time interval between exposure of the target to the candidate and the observation of the capsule to determine whether or not a successful interaction has occurred and the transformation has taken place. |