What is the Difference Between Flow Cytometry and FACS?

Flow cytometry and fluorescence-activated cell sorting (FACS) are both analytical cell biology techniques used to study and sort cells. While they share some similarities, there are key differences between the two methods:

1. Purpose: Flow cytometry is focused on measuring protein expression or co-expression within a mixed population of cells, providing a comprehensive understanding of various cell populations. FACS, on the other hand, is a subtype of flow cytometry that allows cells to be sorted and retained rather than simply analyzed and disposed of.
2. Sorting: FACS uses an electromagnet to sort the sample, while flow cytometry relies on differential light scattering properties of cells. This means that FACS can sort cells with higher precision, leading to less contamination.
3. Sequencing: Flow cytometry typically follows FACS, as FACS is the first step of analyzing a heterogeneous cell mixture.
4. Throughput and Time: FACS can be time-consuming and has limited throughput, as it sorts cells one by one. In contrast, magnetic-activated cell sorting is a faster process that can handle larger cell populations.
5. Equipment and Personnel: FACS requires access to expensive equipment and trained personnel to use it. Flow cytometry instruments, such as benchtop flow cytometers, are smaller and can be used in individual labs.

In summary, flow cytometry is primarily used for cell analysis and measuring protein expression, while FACS is a specialized type of flow cytometry that focuses on sorting and retaining specific cell populations. Both techniques have their advantages and limitations, and the choice between them depends on factors such as sorting precision, throughput, and resource availability.

Comparative Table: Flow Cytometry vs FACS

Flow cytometry and fluorescence-activated cell sorting (FACS) are both cell characterization techniques that have distinct methodologies and outcomes. Here is a table summarizing their differences:

In summary, flow cytometry is used to analyze individual cells and their properties, while FACS is a method for sorting cells based on their optical properties. Both techniques can be used together to provide more comprehensive cell analysis.