It is not recommended to place an ice bucket directly on the collection tube place in a FACS BD Aria machine during cell sorting. The collection tubes are designed to be kept at a specific temperature, typically room temperature or slightly warmer, to maintain the viability and functionality of the sorted cells. Placing an ice bucket nearby could cause the temperature of the collection tubes to drop significantly, which may negatively impact the cells' health and sorting efficiency.

Instead, you can consider placing the ice bucket elsewhere in the workspace, such as on a separate table or shelf, and transferring the sorted cells to the ice bucket after they have been collected. This will help keep the cells at the appropriate temperature while being sorted, and then rapidly cool them down after sorting to prevent any potential damage from heat stress.

It's also worth noting that some FACS machines, including the BD Aria, come equipped with built-in cooling systems that can regulate the temperature of the collection tubes. In these cases, it may not be necessary to use an external ice bucket at all. Be sure to consult your machine's user manual or manufacturer's instructions

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