Simultaneous Chromatographic Quantitation of Drug Substance and Excipients in Nanoformulations Using a Combination of Evaporative Light Scattering and Absorbance Detectors br

Nanomedicines including lipid- and polymer-basednanoparticles and polymer-drug conjugates enable targeted drugdelivery for the treatment of numerous diseases. Quantitativeanalysis of components in nanomedicines is routinely performed tocharacterize the products to ensure quality and propertyconsistency but has been mainly focused on the activepharmaceutical ingredients (APIs) in academic publications. Ithas been increasingly recognized that excipients in nanomedicinesare critical in determining the product quality, stability,consistency, and safety. APIsare often analyzed by high-performance liquid chromatography (HPLC), and it would beconvenient if the same method can be applied to excipients to robustly quantify all components in nanomedicines. Here, we reportthe development of a HPLC method that combined an evaporative light scattering (ELS) detector with an UV-vis detector tosimultaneously analyze drugs and excipients in nanomedicines. This method was tested on diverse nanodrug delivery systems,including a niosomal nanoparticle encapsulating a phytotherapeutic, a liposome encapsulating an immune boosting agent, and aPEGylated peptide. This method can be utilized for a variety of applications, such as monitoring drug loading, studying drug release,and storage stability. The information obtained from the analyses is of importance for nanomedicine formulation development.