What is the role of differential pressure in flow cytometry?

In flow cytometry, differential pressure plays a pivotal role in controlling the hydrodynamic focusing of the sample stream. The primary function of differential pressure is to manage the width of the core stream. This is essential for ensuring that the cells or particles within the sample are aligned and pass through the laser beam one at a time, rather than clustering together.

By adjusting the differential pressure between the sheath fluid and the sample fluid, operators can manipulate the extent of the core stream's width. A narrower core stream increases the chances of detecting individual particles, which enhances the resolution and accuracy of the measurements obtained from the flow cytometer. This precise control allows for optimal performance when analyzing the characteristics of cells, such as size and fluorescence intensity.

While other aspects like temperature and mixing are important in related processes, they do not pertain specifically to the fundamental function of differential pressure in determining the core stream's dimensions and the efficiency of particle detection.