Flow cytometry is a high-throughput technology that can simultaneously analyze multiple cellular markers (surface and/or intracellular) at a single-cell level. It is a powerful technology used to identify, quantify, and monitor cellular phenotypes, signaling pathways, and functional responses in many cell types. Cell sub-populations of interest can also be sorted and collected for downstream applications. Researcher demand has driven the development of a range of flow cytometers to meet the needs and budgets of various labs. Here, we provide some tips to avoid buyer’s remorse when purchasing a flow cytometer.
First, define the lab’s needs; this will aid in creating a list of cytometer “must-haves” and “nice to haves.” Flow cytometry can be used for a range of complex applications, such as immunophenotyping, cell cycle analysis, cell proliferation assays, apoptosis, CRISPR screening, and cell sorting. Understanding the lab’s application(s) and sample type(s) is key to choosing many fundamental cytometer features. Here are some questions to consider:
- Cell sorter versus analyzer: is analysis of the characteristics of cells within a heterogeneous sample, or isolation of one or more sub-populations for a downstream application (e.g., single- cell RNA sequencing or cell culture) required?
- Number of lasers/detectors: how many parameters will routinely be measured simultaneously?
- Laser wavelengths: does the application require any specialty dyes or do the cells express any fluorescent proteins?
- Detector type/sensitivity: are the cells of interest considered small particles (e.g., bacteria or extracellular vesicles)?
- Throughput and sample volume (tubes versus plates): how many samples will typically be acquired per experiment? What is the sample volume range (µL vs mL)?
- Volumetric counting: is cell concentration or absolute cell count required?
- Imaging cytometry: are fluorescent images required?
- Biosafety: is an enclosed, sterile system required?
As technology continues to evolve, the footprint of benchtop flow cytometers is increasingly shrinking without compromising performance. However, lab space available to accommodate the new cytometer, as well as any external components (e.g., fluidics cart or pressure regulator), remains an important consideration. Portability is imperative if performing in-field analysis is a priority for the lab.
Most software packages are designed to cater to various levels of user expertise and are reasonably intuitive. However, thoroughly evaluating the software and user interface of a flow cytometer before purchasing is essential. Consider lab members’ experiences with a lens to the extent of training required for them to run the system independently. Features such as auto-calibration, cytometer performance tracking, and standardization should also be assessed.
Always remember to investigate the vendors’ after- sales service and support: is there a local field service engineer; what is the average response time; is there a remote technical support team; are there additional training and educational resources available?
For many labs, budget may be the primary factor to consider. Regardless of the lab’s financial status, it is important to ensure value for money is achieved. In addition to the upfront cost of the cytometer, other cost considerations include consumables (e.g., sheath fluid, QC/calibration beads, cell sorting chips or cartridges) and service fees if/when the service contract expires.