Browsing by Author "Prenner, Elmar J."

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    Bacterial Production of Selenium and Tellurium Nanostructures and their Biophysical-Chemical Characterization
    (2019-04-29) Piacenza, Elena; Turner, Raymond Joseph; Prenner, Elmar J.; Anikovskiy, Max; Trudel, Simon; Lenz, Markus
    The demand for green and “low carbon” technologies has led to the exploitation of various metal or metalloid – metal(loid) – elements in various applications, among which renewable energy production is one of the most pressing. This tendency is resulting in a rapid accumulation of metal(loid) compounds in the environment, posing the emergency of the decontamination of polluted areas. Since most of the metal(loid)s of high technological and economic interest are scarcely present on our Earth’s crust, their recent increased use has also underlined the need of their reclamation to avoid their depletion. Selenium and tellurium are considered to date “energy-critical elements”, as they are of paramount importance to produce sustainable energy and to advance in the technological and biomedical fields. In view of the need to reclaim metalloids from different environmental matrices, the ability of several microorganisms to bioprocess selenium or tellurium compounds into their less bioavailable elemental states producing metalloid based nanomaterials acquires a double importance in terms of bioremediation strategy and technological relevance. This PhD project presents a deep study regarding the exploration of three different bacterial strains, i.e., Rhodococcus aetherivorans BCP1, Ochrobactrum sp. MPV1 and Stenotrophomonas maltophilia SeITE02, as cell factories for the biosynthesis of selenium or tellurium nanostructures. Key parameters influencing fundamental features of the material at the nanoscale, such as size and morphology, and their recovery (e.g., localization with respect to the bacterial cells) are analyzed in this thesis to lay the groundwork for the optimization of metalloid nanomaterial biosynthesis and the development of ad hoc strategies for their recovery from bacterial cultures. Moreover, the bioprocess strategies used by Ochrobactrum sp. MPV1 and S. maltophilia SeITE02 to cope with selenium toxicity are here explored to shed light into the mechanisms used by different microorganisms to thrive under metalloid pressure. The obtained biogenic selenium or tellurium nanostructures were then physically-chemically characterized, bringing to light (i) the structural similarities between chemogenic and biogenic nanomaterials, (ii) the unique feature of an organic material acting as stabilizing agent of the nanostructures, as well as (iii) their photoluminescence and electrical properties, which can be exploited for their future applications.
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    Biophysical analysis on the interaction of polymeric nanoparticles with biomimetic models of the human lung surfactant
    (2019-11) Daear, Weiam; Prenner, Elmar J.; Anikovskiy, Max; Heyne, Belinda; Ildiko, Badea; Noskov, Sergei Yu
    The human body offers many paths that could be used for drug delivery. The pulmonary route, which is delivery through the lungs, provides many advantages such as; 1) direct access to the lungs and blood circulation and 2) large surface area with a thin barrier of about 500 nm thick. These advantages, in addition to increased patient compliance with inhaled medications, have sparked interest in this route in the field of nanomedicine. Nanoparticles are drug delivery vehicles with many advantages over conventional drug delivery methods. These include the high surface area to volume ratio due to their small size and potential for specific targeting. In the pulmonary route, the air blood barrier is composed of three main layers. The top layer or first point of interaction is through the lung surfactant (LS). This monolayer is composed of 90% lipids and 10% proteins. The lung surfactant’s major role is to reduce surface tension experienced in the lung during breathing cycles in order to prevent lung collapse. Therefore, if nanoparticles are to pass through this monolayer, effects on its stability need to be assessed. In this thesis, a biomimetic model of the LS is developed and its interaction with two biodegradable and biocompatible nanoparticles is tested. Biophysical analysis on the interaction includes the use of Langmuir monolayer pressure-area isotherms, surface potential measurements and visualization through Brewster angle microscopy. Results show that interactions and effects on monolayer elasticity are strongly dependent on electrostatic interactions, charge density of the monolayer, lipid headgroup structure and acyl chain saturation.
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    Biophysical Characterization of Nanoparticle Interactions with Lung Surfactant Models for Enhanced Pulmonary Drug Delivery
    (2017) Lai, Patrick; Prenner, Elmar J.; Edwards, Robert Allan; Amrein, Matthias; Heyne, Belinda; Lavasanifar, Afsaneh
    Inhalable nanoparticles for drug delivery has shown promising results in the treatment of lung disease. The impact of these small sized drug carriers on the lungs is remains unclear. One of the first barriers that nanoparticles will encounter upon inhalation is the lung surfactant that lines each alveolus. This is a single molecule layer of lipids and proteins that forms at the air-water interface on top of the alveolar lining fluid. Its main role is to lower surface tension preventing the collapse of the alveoli during the breathing cycle. Impairing surfactant function results in collapse of the alveolar sacs leading to respiratory distress. The aim of the thesis was to use in vitro studies to identify which components of lung surfactant that are potentially impacted or influenced by the presence of nanoparticles. This was conducted using a model system for lung surfactant made up for phosphatidylcholine, phosphatidylglycerol and the neutral lipid cholesterol. This was compared to a clinical surfactant BLES that is used in surfactant replacement therapy. Surface activity was measured using a Langmuir trough with two Teflon barriers to mimic the air-water interface and compress the surfactant monolayer. Imaging of the monolayer was conducted with Brewster angle microscopy to visualize changes in the organization of the surfactant models. Gelatin and polyisobutylcyanoacrylate nanoparticles are both biocompatible materials that have been tested for inhalable drug delivery and are used in these experiments. In vitro testing was done to evaluate three different methods of adding nanoparticles to the surfactant monolayer to develop a better in vitro model to study nanoparticle surfactant interactions. These nanoparticles were either mixed with surfactant before application on the trough, added to the subphase or sprayed from the air as dry powder. Cholesterol was found to play a major role in nanoparticle-surfactant interactions by enhancing the formation of spike-like structures from the surfactant monolayer. The Langmuir trough was shown to be a useful tool for studying in vitro interactions. Further optimization of the spraying dry powder nanoparticles onto the Langmuir trough can potentially be a useful tool in vitro tool to predict potentially harmful in vivo effects
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    Differential impact of single and binary metal mixtures on membrane biophysics as determined by fluorescence and nuclear magnetic resonance spectroscopy
    (2023-04-14) Lewrenz, Anna-Marie; Prenner, Elmar J.; Fraser, Marie; Lewis, Ian
    Heavy metals are toxic to bacterial and eukaryotic organisms. In humans, they are associated with Alzheimer's disease and various cancers. Metals like gadolinium, cadmium, lead, and mercury can bioaccumulate. Lipids are a known metal target in biomembranes. Although metal-lipid interactions have been studied, interactions of metal mixtures are not well understood. This study of binary mixtures of Gd, Cd, and Pb addresses their impact on membrane fluidity and phase transition from rigid gel to fluid liquid-crystalline phases by using fluorescence spectroscopy, in particular Laurdan generalized polarization (GP). Laurdan GP results showed that Gd with its 3+ charge outcompeted the effects of Cd and Pb and induced the largest rigidification. Binary mixtures of Hg/Cd or Pb/Cd showed a higher affinity of Hg and Pb for chloride than Cd. It is known that under physiological conditions some inorganic metals form chloro-complexes. Speciation was considered by using 113Cd, 199Hg, nuclear magnetic resonance. Mixtures of Pb, Cd, and Hg were examined to determine whether their speciation were similar to calculated speciation. Lastly, the Hg induced cleavage of a specific lipid class, plasmalogens was known without a detailed understanding of the mechanism. 1H and 13C nuclear magnetic resonance were used but more work is needed to determine the final step of the mechanism. These studies investigated potential contributions of metal toxicity at the membrane level for bioaccumulating metals of concern, but also included the impact of metal mixtures, which has not been sufficiently investigated in the field.
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    Explorations towards the production of novel biogenic nanomaterial using Rhodococcus aetherivorans BCP1
    (2023-02-09) Pradhan, Nikhil; Turner, Raymond; Michael, Hynes F.; Prenner, Elmar J.; Anikovskiy, Max
    Nanoparticles are typically synthesized through a variety of physical and chemical methods that have been refined over years of research. However, they can come with a high cost in terms of equipment and chemicals needed, as well as the toxicity of the chemicals used. Recently the use of living organisms as a bionanofactory to produce nanomaterial has emerged as an intriguing idea. Bacteria have evolved over time to handle metal toxicity primarily through reducing metal ions, which can be exploited to produce nanomaterial. Rhodococcus aetherivorans BCP1 is one such bacterium that has been found to display strong metal tolerance and shown the ability to convert toxic metals into a variety of nanomaterials. Thus, exploration was done to further test BCP1’s ability to produce nanomaterials with other metals. Cadmium selenide quantum dots are a type of nanomaterial that is highly sought after. These materials find a variety of uses in electronics and bioimaging, and scaled production of these materials is strongly needed. BCP1 was used to explore the production of CdSe QD from these highly toxic metals, and the particles were characterized to explore their properties. Absorbance peaks at 290 and 500nm were seen amongst all samples however, fluorescence was only observed from one and not characteristic of CdSe QD in literature. Samples displayed large sizes of >100nm which far surpassed the expected range (2 – 10nm) for CdSe QD. BCP1 exposure to Na2SeO3 and CdCl2 results in the production of nanomaterial, however the identity appears to be closer to selenium nanoparticles rather than CdSe QD. Silver nanomaterial is one of the most used nanomaterials, with applications found in modern consumer goods. Since the properties of silver nanoparticles are highly dependent on their size and shape, BCP1 was used to explore the production of size and shape tunable silver nanoparticles. Spherical and cubic silver nanoparticles were produced that displayed absorbance peaks at 290nm and 550-600nm and FRET induced fluorescence was observed at 360nm. 2µm cubic material was also spotted with longer AgNO3 exposure. The particles showed uncharacteristically weak antimicrobial activity against gram positive and negative organisms.
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    Identification and Characterization of Moesin-, PIP2-mediated Solid Particle Phagocytosis
    (2018-08-09) Tu, Zhongyuan; Shi, Yan; Yates, Robin Michael; Amrein, Matthias; Prenner, Elmar J.; Botelho, Roberto
    Phagocytosis is the defining feature of professional phagocytes of the innate immune system. This function is typically carried out by phagocytic receptors on the cell surface. These receptors can mediate binding and engulfment of solid particles. However, these phagocytic receptors have evolved very recently in history comparing to phagocytosis as a conserved cellular function. This suggests a primordial form of phagocytosis might exist. Years ago, our laboratory uncovered an expected phagocytic mechanism that solid particle can bind to membrane lipids on phagocytes to trigger lipid sorting. Consequently, this can lead to phagocytosis akin to FcγR-based phagocytosis regarding its dependence on Immunoreceptor Tyrosine-based Activation Motif (ITAM), Src-family kinases, Syk, and phosphoinositide 3-kinase (PI3K). Based on these findings, we proposed a hypothetical mechanism for solid particle phagocytosis termed “Signaling Equivalent Platform” (SEP). In short, membrane engagement with solid structures, either via ligand/receptor binding or merely being stabilized by an approaching solid surface will lead to a shared downstream pathway with the same dependence on ITAM and Syk. Both modes of phagocytosis are equivalent for its activation by solid structures. However, the identity of the ITAM-containing molecule and the exact involvement of lipid during solid particle phagocytosis under SEP is still unclear. This thesis serves to strengthen the idea of SEP by identifying the ITAM-containing molecule and further characterizing the involvement of the ITAM-containing molecule and lipids during solid particle phagocytosis. We used a generic ITAM sequence as a probe and identified moesin as the ITAM-containing molecule from the mouse genome. We further demonstrated that a solid structure binding to the cell surface leads to autonomous accumulation of phosphatidylinositol 4, 5-bisphosphate (PIP2) to the site of contact, which attracts moesin, a conserved structural linker, to the plasma membrane. Moreover, Moesin, via its ITAM, is sufficient to activate phagocytic programming including Syk and downstream signaling that is virtually identical to that initiated by Fcγ receptors. Bioinformatic analysis suggested that this moesin-mediated signaling predates modern Fcγ and immune receptors. This thesis, therefore, reveals an evolutionarily conserved moesin-, PIP2-mediated signaling platform for the evolutionarily conserved phagocytosis that provides essential components for modern ITAM-based signaling cascades.
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    Lead Interactions Affect the Fluidity and Lateral Organization of Complex Lipid Membranes
    (2018-03-26) Mundle, Robyn Louise; Prenner, Elmar J.; Gailer, Jürgen G.; Turner, Raymond Joseph; Noskov, Sergei Yu
    Elevated levels of the heavy metal lead are associated with various toxic effects which may also be due to interactions with lipid membranes. Bilayer and monolayer techniques were used to monitor lead interactions with biomimetic and polar lipid extracts. Anionic and zwitterionic lipids as well as saturated and monounsaturated fatty acids were compared. Permeabilization of model membranes by lead was assessed by quantifying fluorescent dye release, whereby leakage readily occurred upon Pb2+ incubation. Fluidity and phase transition changes were investigated by laurdan generalized polarization and dynamic light scattering. Electrostatic lipid targeting by lead induced membrane rigidification which varied with the negative charges within lipid structures. Lead effects on the lateral organization of monolayers were characterized by surface pressure- and surface potential – area isotherms and Brewster angle microscopy. Pb – induced domain formation depends on the number and localization of the phosphate groups on various phosphatidylinositols.
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    Membrane Interactions of Cobalt and Nickel
    (2018-08-20) Umbsaar, Jenelle; Prenner, Elmar J.; Zaremberg, Vanina; Gailer, Jürgen G.; Noskov, Sergei Yu
    The metals Cobalt (Co) and Nickel (Ni) are common industrial metals which are becoming increasingly prevalent in everyday life. Despite their ubiquity, disruption to homeostasis of trace metals can have severe consequences, as elevated levels of Co2+ and Ni2+ have been associated with various toxic effects. The mechanisms by which metals including Co2+ and Ni2+ exert these effects are not fully understood and may involve various biomolecules. The primary focus of this thesis is on the interactions of Co2+ and Ni2+ with lipid membranes, as disruption to membrane properties may have consequences for transport, signalling, and overall cellular integrity. This study has shown that Co2+ and Ni2+ rigidify membranes containing negatively-charged lipids in both simple and complex model membranes. Additionally, Co2+ and Ni2+ were found to affect respiration and neutral lipid content in the model organism S. cerevisiae, suggesting that both direct and indirect effects on membrane properties may occur.
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    Novel Electrostatic Mechanisms Controlling the Conformational Switching of L-plastin
    (2018-06-12) Fanning, John Keenan; Noskov, Sergei Yu.; Vogel, Hans J.; Maccallum, Justin L.; Prenner, Elmar J.; Ng, Kenneth Kai Sing
    L-plastin is an actin-bundling protein that promotes the motility of both hematopoietic and metastatic cancer cells. The high definition structure of the calcium-binding regulatory domain of human L-plastin was recently determined, allowing computational research on this portion of the protein. The Drude polarizable force field was used to provide accurate computational simulations of the calcium-binding domain in conjunction with experimental validation to shown that L-plastin can regulate calcium-binding, and thus actin-bundling, through internal electrostatic interactions. Through this work the Drude force field was also benchmarked, to show that it provides comparable results to classical force fields with the added ability to simulate polarizability. Overall, a novel mechanism which allows L-plastin to self-regulate its calcium-binding affinity was developed.
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    Rapid Non-genomic Actions of Cortisol in Fish
    (2019-12-20) Das, Chinmayee; Vijayan, Mathilakath M.; Prenner, Elmar J.; Wildering, Willem C.; Thundathil, Jacob C.; Lee, Lucila E. J.
    Cortisol, the primary glucocorticoid (GC) in teleosts signals through either the genomic pathway, by activating the intracellular glucocorticoid receptor (GR) and/or the mineralocorticoid receptor (MR), or through non-genomic pathways. However, the mechanism of action of non-genomic cortisol signalling is far from clear, and there is a complete lack of consensus as to the physiological significance of this rapid action. The major goal of this thesis was to determine the mode of action of cortisol in bringing about rapid changes in intracellular Ca2+ levels [iCa2+] as a non-genomic response, and to assess the physiological consequences of this rapid effect at the cellular and organismal level. This was tested using rainbow trout (Oncorhynchus mykiss) hepatocytes (non-excitable) and zebrafish (Danio rerio) muscle (excitable) explant as in vitro and ex vivo models, respectively. The results indicate that a direct interaction of cortisol with the calcium release-activated (CRAC) channel may be responsible for the rapid increase in [iCa2+] due to cortisol. This increase in [iCa2+] with cortisol played a key role in the translocation of intracellular GR to the plasma membrane. This was evident because inhibition of the CRAC channel abolished the colocalization of GR to the caveolin-1 on the plasma membrane of hepatocytes. Cortisol also stimulated a rapid increase in [iCa2+] in zebrafish muscle explants, underscoring a conserved non-genomic role for cortisol in rapidly increasing [iCa2+] in excitable and non-excitable cells. A zebrafish tail-fin amputation model was used to investigate the physiological role of non-genomic and genomic cortisol signalling in regulating epimorphic regeneration. Cortisol rapidly increased [iCa2+] at the amputated site, and this corresponded with an increased ORAI1 (protein subunit of CRAC) expression at the site. Also, an increase in cell proliferation of ORAI1 expressing cells and blastema formation was evident at 24 h in response to cortisol stimulation, but absent in the GR knockout and MR knockout larvae, suggesting that this CRAC channel protein may be both non-genomically and genomically regulated by cortisol. Taken together, this thesis represents a significant contribution to the mechanism of action of rapid non-genomic effects of cortisol, which is essential to our understanding of the role of cortisol in stress adaptation in vertebrates.
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    Regulation of neutral lipid metabolism through phosphorylation of the yeast acyltransferase Gpt2
    (2018-10-04) Tavassoli, Marjan; Zaremberg, Vanina; Chua, Gordon; Prenner, Elmar J.
    Glycerol-3-phosphate acyltransferases (GPATs) catalyze the first step of glycerol-3-phosphate acylation at the sn-1 position producing lyso-phosphatidic acid. This is the committed and rate limiting step in de-novo synthesis of phosphatidic acid, the key intermediate in the glycerophospholipids and triacylglycerols (TAG) biosynthetic pathways. Two GPATs have been identified in S cerevisiae, Gpt2p and Sct1p. The role of phosphorylation in the serine-rich C-terminal tail of Gpt2p is unknown. In this work is shown that lack of phosphorylation on three conserved phosphorylation sites (S664, S668, S671) of Gpt2p alters protein stability, activity and neutral lipid metabolism. Specifically, a triple Gpt2p mutant (Gpt2-3A) where all these three residues were converted to alanine to mimic dephosphorylation induce a rise in the protein abundance, displayed more activity and resultedi in higher accumulation of DAG and TAG during exponential phase of growth. Lack of phosphorylation on Gpt2p delayed TAG lipolysis upon growth resumption from stationary phase which might be due to a futile TAG cycle that slows down mobilization of produced acyl-chains channeled for the formation of phospholipids. Unregulated Gpt2p probably remains constitutively active and displaces Sct1p in exponential phase. Notoriously, Sct1p is found associated with lipid droplets in cells carrying Gpt2-3A mutant. Considering Sct1p has never been identified in lipid droplets proteomes this consequence of having a constitutively de-phosphorylated Gpt2p might explain the alterations seen in neutral lipid metabolism of this mutant cells.
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    Role of diacylglycerol in the cellular response to lysophosphatidylcholine analogues
    (2019-09-19) Ganesan, Suriakarthiga; Zaremberg, Vanina; Prenner, Elmar J.; Ro, Dae Kyun
    Diacylglycerol (DAG) is a key signaling lipid and intermediate in lipid metabolism. Our knowledge of DAG distribution in cell membranes is limited. Using the C1 domain from mammalian PKCδ and PKD, we monitored the localization of yeast cytosolic-facing pools of DAG for the very first time and investigated alteration in distribution in response to conditions where DAG levels were known to be altered. Two main pools were monitored over time using DAG sensors. One stable pool was associated with vacuolar membranes and a second temporal pool was localized to sites of polarized growth. Dynamic changes in DAG distribution were observed during resumption of growth from stationary phase, when DAG is used to support phospholipid synthesis for membrane proliferation. Vacuolar membranes experienced constant morphological changes displaying DAG enriched microdomains co-existing with liquid-disordered areas demarcated by Vph1. Formation of these domains was dependent on TAG lipolysis. DAG domains and puncta were closely connected to lipid droplets and our findings suggest that DAG could link lipid droplets and tubular ER upon growth resumption from stationary phase. DAG polarization was regulated by DAG to PA conversion upon TAG mobilization, phosphatidylserine synthesis/traffic and sphingolipid synthesis in the Golgi. We also investigated another condition where DAG accumulates, which is in cells treated with the lysophosphatidylcholine analogue edelfosine. We hypothesized that by manipulating levels of PA and DAG, cells confer resistance to edelfosine, possibly due to mislocalized PA and DAG which prevent cellular response to edelfosine. Experiment where PA and DAG levels were manipulated clearly support a protective role of PA in the response to edelfosine. Interestingly, edelfosine induced drastic change in the localization of DAG. A synthetic genetic array analysis pointed to endocytic and retrograde trafficking proteins as key players in modulating DAG distribution. Many of these trafficking mutants were also resistant to edelfosine, suggesting mislocalization of DAG is advantageous in the presence of edelfosine. In addition, a putative lipase Ydr444w and the PI4P phosphatase Sac1 were also identified as novel regulators of DAG homeostasis. An up-to-date map of the spatiotemporal distribution of the cytosolic pools of DAG in yeast emerged from this body of work.
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    Synthesis and optical characterization of amphiphilic benzimidazole-based cyanine dyes
    (2020-04-14) Roth, Sophia Marie; Heyne, Belinda; Sutherland, Todd C.; Back, Thomas George; Anikovskiy, Max; Prenner, Elmar J.
    Cyanine dyes have seen use in a plethora of applications since the first report of their synthesis in 1856. While historically the utility of this class of compounds has been derived from their ability to act as photographic sensitizers in silver halide photography, they have maintained relevance through their applicability to other fields, including bioimaging and organic photovoltaics. The capacity of cyanine dyes to stand the test of time is due predominantly to their favourable optical properties. One attribute known to alter these photophysical characteristics, however, is the propensity of many cyanine dyes to aggregate in solution; when going from monomeric compounds to self-assembled structures, absorption and emission features change. To effectively obtain the optical properties desired of cyanine dyes for diverse use, their aggregation tendencies must be understood. The work outlined herein focuses on studying the structure-aggregation relationships of a family of amphiphilic benzimidazole-based trimethine cyanine dyes, whose chlorinated derivatives are known to form aggregates of distinct morphology in aqueous solution. By systematically modifying the chromophore’s core, it was hoped that the structural features that dictate their aggregation could be elucidated. Synthetic efforts to attain the dyes under investigation are highlighted in the first research chapter of this thesis. While the conventional means of preparing these compounds worked for some of the target derivatives, they failed for others. This deficiency in the traditional route warranted the development of a new synthetic method, which saw success in preparing a set of previously elusive compounds. Next, the optical properties of these newly-synthesized dyes were explored, under monomer and aggregate conditions, in the second research chapter. Through both empirical and computational means, it was found that the presence and positioning of halogens on the studied dyes had an effect on the photophysical properties of the monomers as well as aggregation tendencies. This thesis concludes with a summation of the work completed to date, and an accompanying perspective on what the future of this project may bring.
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    Vaping Additives Affect Lateral Organization and Functionality of Lung Surfactant Model Systems
    (2022-07-28) Van Bavel, Nicolas; Prenner, Elmar J.; Anikovskiy, Max; Loebenberg, Raimar
    Recent use of THC-based vapes has led to an outbreak of respiratory health issues. While the pathology is unresolved, common symptoms point to dysfunction of the lung surfactant (LS). This is a lipid-protein monofilm situated at the air-water interface in alveolar sacs, which acts to lower surface tension, preventing lung collapse during respiration. Inhaled substances that reach the alveoli will encounter LS. Certain vape additives have been identified as potential causative agents, these being tetrahydrocannabinol and cannabidiol, commonly found in THC products, as well as vitamin E and its derivative vitamin E acetate. The lipophilic nature of these additives may allow them to partition into the monofilm, wherein they could interact with lipids to disrupt proper function. The aim of this thesis was to use model surfactants to better understand the interactions between vaping additives and the primary lipid components of lung surfactant. These films were made up of phosphatidylcholines, phosphatidylglycerols, and cholesterol. Additionally, the clinical surfactant BLES was also used and compared to the model systems. BLES is used in surfactant replacement therapy, making it a good physiological counterpart to the simple model films studied. Surface activity of the films were measured using a Langmuir-Blodgett trough which allowed for compression and expansion of the films, mimicking respiration. Changes to the lateral organization of the films was conducted with Brewster angle microscopy. Visualization of BLES was also carried out with atomic force microscopy, which allowed for higher resolution images of the surfactant’s molecular architecture. Vape additives were found to destabilize domain formations in most systems, often accompanied by fluidization of the film. The effects on BLES provided a unique insight into the mechanistic action of additive induced surfactant dysfunction. Crucial multilayer structures that form on the surface of the film during compression were abolished in the presence of vitamin E acetate, reducing the surfactants ability to maintain a low surface tension. The Langmuir-Blodgett trough has demonstrated to be useful for studying in vitro interactions between lipids and vape additives. With further optimization, this method may be used to predict in vivo effects of vape additives.