# Comparing the Activity of Peripheral Blood Mononuclear Cells Frozen Under Electromagnetic Field Freezing and Standard Slow‐Freezing

## TL;DR

This paper compares two methods for freezing blood cells and finds that one method is faster without reducing cell quality.

## Contribution

The study introduces a faster freezing method for PBMCs that maintains cell quality and allows earlier storage in liquid nitrogen.

## Key findings

- The EMF method freezes PBMCs in 0.25 hours compared to 3 hours with the standard method.
- Cell viability and activity were equivalent between the two freezing methods.
- The EMF method improves operational efficiency for facilities storing PBMCs.

## Abstract

Peripheral blood mononuclear cells (PBMCs) are cells obtained from the blood that are used not only in clinical tests but also in various research applications. The slow‐freezing (SLF) method, currently the standard for PBMC cryopreservation, involves extended storage at −80°C before transfer to liquid nitrogen. Delays in this transfer, such as overnight or weekend holds, risk a gradual decline in cell viability. Additionally, variability in freezing duration can lead to inconsistent cell quality, emphasizing the need for an alternative freezing method that allows for more timely transfer to liquid nitrogen. This study is aimed at clarifying whether the method of using a freezer with an applied electromagnetic field (EMF) is superior to the currently used standard SLF method for PBMC cryopreservation. A comparison of the number of viable cells, cell viability, and cell activity showed that the EMF method was equivalent to the SLF method. However, the shortest time required for freezing was significantly shorter with the EMF method than the SLF method (0.25 vs. 3 h), allowing for earlier transfer of PBMC to liquid nitrogen. This demonstrates that the EMF method offers an advantage in operational efficiency, particularly for facilities that routinely process and store PBMCs, such as biobanks and other storage‐focused departments.