Two-Component Langmuir Monolayers and LB Films of DPPC with Partially Fluorinated Alcohol (F8H9OH)

Effect of perfluorotetradecanoic acid on the morphology of a photopolymerizable phospholipid monolayer at the air‐water interface

“…Again, the principal effect of PF is fluidization of the monolayer and the tendency to disperse condensed phase regions of the films, even with nominal cross-linking. This is consistent with the findings of other researchers, who hypothesized that perfluorinated compounds could be absorbed into lipid membranes and thereby increase membrane fluidity (Harada et al, 2005;Hu et al, 2003;Nakahara, 2016;Nakahara et al, 2013;Nakahara & Shibata, 2012;Oldham et al, 2012;Xie et al, 2010;Xiea et al, 2011). Insight into how this might be occurring at a molecular level has been suggested by Matyszewska et al (Dencheva-Zarkova & Genova, 2020), who have reported on the influence of perfluorocarbons compounds on two phospholipids 1,2-dipalmitoyl-snglycero-3-phosphocholine and 1,2-dimyristoyl-sn-glycero-3-phosphocholine using a combination of Langmuir monolayer studies in combination with molecular dynamic simulation.…”

“…While we will not attempt to determine this here, it is likely that the mixed film is phase‐separated but quite complicated in terms of spatial distribution of surfactants, with the bright patches of the film consisting of condensed phase regions of phospholipid and the surrounding low reflectivity regions are water, PF and expanded phase phospholipid. Similar compositional structures have been described for mixed perfluorocarbon‐phospholipid systems elsewhere (e.g., Courrier et al, 2003; Krafft et al, 2001; Nakahara, 2016; Nakahara et al, 2013; Nakahara & Shibata, 2012; Nakamura et al, 2007; Oldham et al, 2012; Xie et al, 2010; Xiea et al, 2011) though the precise film makeup will almost certainly depend upon subphase conditions and the chemical structure of the film constituents.…”

“…In this work, we have focused on the use of enantiomerically pure diacetylene‐functionalized phospholipid 1,2‐bis(10,12‐tricosadiynoyl)‐sn‐glycero‐3‐phosphocholine (Diyne PC) as the hydrogenated component of the film and PF as the perfluorinated component (Scheme 1). Miscibility in phospholipid‐fluorocarbon monolayers has been extensively investigated (Krafft et al, 2001; Nakahara et al, 2013; Nakahara & Shibata, 2012; Nakamura et al, 2007; Oldham et al, 2012; Xie et al, 2010; Xiea et al, 2011), and studies on many different mixed systems have been reported. While the precise effects observed in these systems depends strongly upon chemical structure of the film constituents as well as subphase conditions (e.g., pH, presence of salts), the most reported effect has been that perfluorocarbon‐based surfactants tend to fluidize phospholipid monolayers and, in some cases, can inhibit formation of liquid‐condensed phospholipid domains (Dencheva‐Zarkova & Genova, 2020; Harada et al, 2005; Nakahara, 2016; Nakahara et al, 2013; Nakahara & Shibata, 2012; Nakamura et al, 2007; Oldham et al, 2012; Xie et al, 2010; Xiea et al, 2011).…”

“…Miscibility in phospholipid‐fluorocarbon monolayers has been extensively investigated (Krafft et al, 2001; Nakahara et al, 2013; Nakahara & Shibata, 2012; Nakamura et al, 2007; Oldham et al, 2012; Xie et al, 2010; Xiea et al, 2011), and studies on many different mixed systems have been reported. While the precise effects observed in these systems depends strongly upon chemical structure of the film constituents as well as subphase conditions (e.g., pH, presence of salts), the most reported effect has been that perfluorocarbon‐based surfactants tend to fluidize phospholipid monolayers and, in some cases, can inhibit formation of liquid‐condensed phospholipid domains (Dencheva‐Zarkova & Genova, 2020; Harada et al, 2005; Nakahara, 2016; Nakahara et al, 2013; Nakahara & Shibata, 2012; Nakamura et al, 2007; Oldham et al, 2012; Xie et al, 2010; Xiea et al, 2011). The photopolymerization (cross‐linking) of linear diacetylenes is topochemical, requiring appropriate packing and molecular alignment to achieve effective polymerization and thus it is reasonable to anticipate that addition of a fluidizing component like PF will significantly impact chiral domain structure and more broadly, properties of the film at the air water interface pre‐ and post‐polymerization.…”