LC-UV as tool for nanovectorized anticancer peptide quality control: evaluation of encapsulation efficiency

Many peptides have today a recognized and growing therapeutic interest. However, their administration is not an easy task, since systemically administrated peptides may suffer from several issues such as rapid elimination or unspecific biodistribution. Moreover, many compounds of this emerging class of therapeutics have their targets at the intracellular level, adding another challenge to their therapeutic success.
LB19 is a peptidic selective inhibitors of LDHB that catalyzes the conversion of lactate + NAD to pyruvate + NADH + H+, a new therapeutic approach for cancer therapy. The necessity of intravenous administration of LB19 lead to the development of liposomes as drug carriers, combining the protective properties of PEG (stealth liposomes) with the transfection properties of pH-sensitive lipids.
This general concept raises the need to develop analytical tools enabling the determination of the encapsulation efficiency of LB19 into these nanocarriers and quantitatively demonstrate their ability to achieve intracellular delivery of their payload.
In this project, a LC-UV method was developed to selectively quantify this new anticancer peptide in liposomes. More particularly, we generated stability data of LB19 to support its formulation development. The LC-UV method was employed to study the adsorption of the peptide and demonstrate the impact of the adsorption behaviour on quantitative analysis during the evaluation of the encapsulation efficiency of liposomes.
Altogether, this analytical part of our project has the potential to control the quality of the formulated LB19 loaded liposomes, and has also a goal to provide a LC-MS/MS method for the intracellular assay of the peptide on long run.