Facile Separation of PEGylated Liposomes Enabled by Anti-PEG scFv

Abstract

PEGylated nanocarriers have gained increasing attention due to reduced toxicity and enhanced circulation compared with free drugs. According to guidances of drug regulatory departments worldwide, it is crucial to determine free and liposomal drug concentrations; however, the conventional used separation methods including dialysis, ultrafiltration, and solid-phase extraction (SPE) have drawbacks of time-consuming, drug leakage, environmental pollution or error bias of trace level drug. Here we developed a facile PEG-scFv-based separation method combined with HPLC to quantify free doxorubicin (DOX) and liposomal DOX in plasma. Anti-PEG single chain variable fragment antibody (PEG-scFv) was adopted to sediment PEGylated liposomes by simple incubation and low speed centrifugation. Compared to SPE, it demonstrated sufficient accuracy and sensitivity to evaluate free and liposomal DOX with intact liposomes. Therefore, it can serve as an alternative approach of SPE, which is suitable for quality assessment and pharmacokinetics evaluation of PEGylated liposomal drugs and possible other PEGylated nanocarriers.

Lipid‐Based Nanocarriers Enabled Oral Delivery of Oleanolic Acid Derivative DKS26 for Diabetes Management

“…As expected, PEGylated liposomes were efficiently separated according to our previous report. [ 27 ] 40 micrograms of scFv completely separated sLip containing 100 µg of lipid. However, the separation of sND was relatively difficult, which might be due to the smaller size of sND than that of sLip.…”

Comment on “Optimal centrifugal isolating of liposome–protein complexes from human plasma” by L. Digiacomo, F. Giulimondi, A. L. Capriotti, S. Piovesana, C. M. Montone, R. Z. Chiozzi, A. Laganá, M. Mahmoudi, D. Pozzi and G. Caracciolo,Nanoscale Adv., 2021,3, 3824

“…[62][63][64] Tang et al recently demonstrated how protein-induced aggregation of liposomes could also be used to study drug leakage from liposomes using centrifugation. 65 We however nd the procedure unsuitable for studying the protein corona of non-aggregating nanoparticles, which from a clinical perspective are of much higher relevance than aggregating nanoparticles. We would furthermore like to stress that we do not nd that centrifugation should be avoided when studying the protein corona of high-density particles such as gold, silver, iron, or even silica or polystyrene.…”

Interplay between Liposomes and IgM: Principles, Challenges, and Opportunities

“…[16] Among immunoglobulins, IgM (Ighm, lg mu chain C region) was found to be the most abundant in liposomal protein corona, whose content was even higher than that of IgG (Ighg1 or Ighg2b, Ig gamma-l or 2B chain C region). [17][18][19] Although surface modification endows liposomes with better in vivo properties such as prolonged circulation time or specific targeting ability, it may also change the corona composition. By preparing liposomes with different targeting ligands (e.g., peptides and small molecules) and molar ratios, we identified that IgM was ubiquitously adsorbed on liposomes with different modifications.…”

“…The anti‐PEG scFv was used to precipitate PEGylated liposomes by simple incubation and low‐speed centrifugation (100–2000 × g for 10 min), demonstrating sufficient accuracy and sensitivity compared to conventional solid‐phase extraction method. [ 18 ] We hope the anti‐PEG scFv could provide new effective methods for protein coronas analysis and pharmacokinetic evaluation of PEGylated liposome drugs and other PEGylated nanomedicines.…”