Timer Activated Delay

To gain precise control over your chemistry in complex protocols, consider using the Timer Activated delay option to specify when to launch a protocol step. You can make sure processing time is the same for every plate, to ensure, for example, that reagent remains in every plate for a minimum or uniform time period.

This is especially beneficial when designing a multi-step BioStack protocol that is run with varying numbers of plates in the stack. If the timer is not used in this scenario, assay performance could be significantly different in a protocol run of 30 plates versus a 10-plate run.

A Timer-Activated Delay puts start and end steps in the protocol. To remove the delay from the protocol, you must delete both steps: hold the Ctrl key to select both steps simultaneously.

Examples:

Simple Delay

To use the timer successfully, you must first determine the approximate duration of your protocol steps. Specify a sufficient time lapse to both complete the steps and to delay the process to suit your assay.

Define a Delay step.

When a 'timer activated' delay is defined, the LHC adds a start and end event to the protocol.

The start and end events create a step container, similar to a Loop or BioStack run.

The example above shows how to manage the start time of two sequential operations, or steps. In this example, the timer is started prior to the Peri-pump dispense operation and ended prior to the Syringe pump dispense operation. The specified 5-minute delay is much longer than the duration of the Peri-pump dispense operation..

Nested Delays

The timer activated delay can be nested within another time controlled series of protocol steps. This may be necessary to specify multiple processing start times for a complex series of steps, including loops and BioStack steps.

This example uses a BioStack rack of plates. The process requires that each plate in the rack be filled with 250 µL from the Peri-pump and then, after 1 hour, the plate is washed. The protocol will fill each plate in the rack, restack the plates, and then wash each plate 1 hour after it was filled. The dispense and wash activities are each performed within a 1 minute processing window created by the timers. This timer configuration ensures that the timing of washing after dispensing is identical for every plate .

Once again, make sure there is sufficient time to process all the steps within the step containers, and to incorporate any desired incubation or rest periods when defining the timer activated time period.