Difference Between CFSE and LFSE

The key difference between CFSE and LFSE is that the term CFSE stands for a chemical compound, whereas the term LFSE stands for a theory in chemistry.

The term CFSE stands for the chemical compound carboxyfluorescein succinimidyl ester. It is a dye that we mainly use for staining cells for fluorescence. The term LFSE, on the other hand, stands for ligand field stabilization energy, which is a term in the Ligand field theory.

CONTENTS

1. Overview and Key Difference
2. What is CFSE 
3. What is LFSE
4. Side by Side Comparison – CFSE vs LFSE in Tabular Form
5. Summary

What is CFSE?

The term CFSE stands for the chemical compound carboxyfluorescein succinimidyl ester. It is useful as a fluorescent cell staining dye. This substance is cell-permeable and covalently couples with intracellular molecules via the succinimidyl group of CFSE. Notably, this occurs with intracellular lysine residues and other amine sources. Due to this coupling reaction between CFSE molecules and intracellular molecules, this fluorescent dye is retained within cells for extremely long periods.

The chemical formula of CFSE molecule is C25H15NO9. The molar mass is 473 g/mol. Often, CFSE gets confused with CFDA-SE (carboxyfluorescein diacetate succinimidyl ester) due to their close similarity. But they are not the same molecule, and CFSE is highly cell-permeable compared to CFDA-SE. Also, this second compound is non-fluorescent.

Originally, the CFSE compound was produced as a fluorescent dye that can stably label lymphocytes and track their migration through blood within animals for a long time. Subsequently, it was revealed that the dye can be used to monitor lymphocyte proliferation. However, if we use a high concentration within the cells, it is toxic to the animal.

What is LFSE?

The term LFSE stands for ligand field stabilization energy which is a term in the Ligand field theory. It describes bonding, orbital arrangement and other characteristics of coordination complexes. This theory represents an application of molecular orbital theory to transition metal complexes. Usually, a transition metal has nine valence atomic orbitals. There are five d orbitals, one s orbital and three orbitals that can be taken as valence shells. These orbitals contain the appropriate energy to form a chemical bond with a ligand. This amount of energy is called the ligand field stabilization energy. Moreover, this chemical concept is usually applied according to the geometry of the complex. Mostly, it explains about the octahedral complexes containing six ligands per molecule.

What is the Difference Between CFSE and LFSE?

The term CFSE stands for the chemical compound carboxyfluorescein succinimidyl ester while the term LFSE stands for ligand field stabilization energy which is a term in the Ligand field theory. Therefore, the key difference between CFSE and LFSE is that the term CFSE stands for a chemical compound, whereas the term LFSE stands for a theory in chemistry. To be more specific, CFSE is a fluorescent dye while LFSE is the energy required to stably form a coordination complex.

The following infographic summarizes the difference between CFSE and LFSE in tabular form.

Summary – CFSE vs LFSE

The term CFSE stands for the chemical compound carboxyfluorescein succinimidyl ester while the term LFSE stands for ligand field stabilization energy which is a term in the Ligand field theory. Therefore, the key difference between CFSE and LFSE is that the term CFSE stands for a chemical compound, whereas the term LFSE stands for a theory in chemistry.