What is 1,2-Distearoyl-sn-glycero-3-phosphocholine?

1,2-Distearoyl-sn-glycero-3-phosphocholine (DSPC) is a non-pyrogenic phospholipid containing saturated long-chain (18:0) stearic acid inserted in the sn-1 and sn-2 positions. It can be used to form liposomes capable of loading selected molecules. Formulations containing DSPC have been used to develop lipid nanoparticles for delivery of mRNA in vaccines. This liposomal product improves the bioavailability and targeting of drugs and is widely used in drug delivery systems.

Simultaneous encapsulation of hydrophilic and lipophilic molecules in DSPC liposomes

This study shows simultaneous incorporation of two hydrophobic molecules and a hydrophilic molecule into distearoylphosphatidylcholine (DSPC) liposomes. Pinocembrin and cholesterol are incorporated in the lipidic membrane while resazurin is encapsulated in the aqueous center. The thermotropic behavior of liposomes as a function of the additives was studied with differential scanning calorimetry and the morphology was observed by SEM. A high percentage of entrapment was found for different concentrations of pinocembrin. Cholesterol does not interfere with the incorporation efficiency of pinocembrin and improves the distribution in the membrane but decreases the dissolution stability of liposomes due to steric hindrance in the bilayer. Encapsulation efficiency of resazurin was close to 50%. This molecule also interacts with the polar heads of the phospholipids. This research offers an alternative formulation by using DSPC liposomes as carrier of molecules with different polarity to evaluate the cytotoxicity of pinocembrin in cancer cell lines.  

Toxicological evaluation of 1,2-Distearoyl-sn-glycero-3-phosphocholine

In the inhalation field, lipids such as egg phosphatidylcholine (PC), 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and dipalmitoylphosphatidylcholine (DPPC), are considered to be generally recognized as safe (GRAS), comprising materials that are endogenous to the lungs and locally present in large quantities. Indeed, PC, DSPC and DPPC may be used to form liposomes which are known to promote an increase in drug retention time and reduce the toxicity of drugs after administration. Unfortunately, published literature guidance about the safety evaluation of these lipids as pharmaceutical excipients for use in inhaled products and about application for marketing authorization, is very limited. The purpose of this article is to review the potential toxicity of DSPC for pulmonary administration. Given the use of air and vehicle controls in a range of inhalation toxicology studies as well as negative genotoxicity and also reproductive toxicity results, it is thought that the use of DSPC is shown to be safe for pulmonary administration.

References

[1] O. OHGODA  I. R. Toxicological evaluation of DSPC (1,2-distearoyl-sn-glycero-3-phosphocholine)[J]. Fundamental Toxicological Sciences, 2020, 26 1: 55-76. DOI:10.2131/fts.7.55.

[2] MARIANA R. ROMERO-ARRIETA; Silvia P C; Elizabeth Uria Canseco. Simultaneous encapsulation of hydrophilic and lipophilic molecules in liposomes of DSPC[J]. Thermochimica Acta, 2020. DOI:10.1016/j.tca.2019.178462.