Surface Enrichment of Surfactants in Amorphous Drugs: An X-ray Photoelectron Spectroscopy Study

• DOI: 10.1021/acs.molpharmaceut.1c00786
• Publication Date: 2022-01-21T14:30:02Z
• Authors: Junguang Yu; Yuhui Li; Xin Yao; Chailu Que; Lian Huang; Ho-Wah Hui; Yuchuan Gong; Feng Qian; Lian Yu
• Keywords: Miscibility

Surfactants are commonly incorporated into amorphous formulations to improve the wetting and dissolution of hydrophobic drugs. Using X-ray photoelectron spectroscopy, we find that a surfactant can significantly enrich at surface an drug, up 100% coverage, wihout phase separation in bulk. We compared four different surfactants (Span 80, Span 20, Tween 20) same host acetaminophen 80 hosts (acetaminophen, lumefantrine, posaconazole, itraconazole). For each system, bulk concentrations were 0, 1, 2, 5, 10 wt %, which cover typical formulations, component miscibility was confirmed by differential scanning calorimetry. all systems investigated, observed significant enrichment surfactants. containing surfactants, strongest occurred for most lipophilic (lowest HLB), with nearly full coverage. doped drugs, effect increases hydrophilicity drug (decreasing log P). These effects arise because low-surface-energy molecules (or molecular fragments) tend liquid/vapor interface. This study highlights potentially large difference between compositions formulation. Given their high mobility low glass transition temperature, impact its stability, wetting, dissolution.