Effect of Lipid Composition and Stirring Dynamics on Oxygen Microbubble Stability and Oxygen Release

IF 3.7 2区化学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Langmuir Pub Date : 2025-01-15 DOI:10.1021/acs.langmuir.4c04104

Kenta Kakiuchi, Mark Andrew Borden

{"title":"Effect of Lipid Composition and Stirring Dynamics on Oxygen Microbubble Stability and Oxygen Release","authors":"Kenta Kakiuchi, Mark Andrew Borden","doi":"10.1021/acs.langmuir.4c04104","DOIUrl":null,"url":null,"abstract":"Lipid-coated oxygen microbubbles (OMBs) are being investigated for biomedical applications to alleviate hypoxia such as systemic oxygenation and image-guided radiosensitization therapy. Additionally, they hold potential for boarder application as oxygen carriers beyond the biomedical filed. Understanding the stability and oxygen release properties of OMBs in dynamic aqueous environments is critical for these applications. In this study, we found that OMBs composed of longer acyl chain phospholipids (DSPC and DBPC) were stable in storage for at least 1 week, unlike the shorter acyl chain phospholipid (DPPC). OMBs were also more stable with a diacyl PEG–PE emulsifier compared with single-chain PEG-40 stearate. Dilution of OMBs did not alter the average diameter. While previous studies have examined the theoretical and experimental aspects of oxygen release from OMBs under static conditions, quantitative evaluations of OMB dispersions under dynamic stirring conditions remain limited. Here, we introduce a novel oxygen measurement method that quantitatively tracks the transition of the dissolved oxygen concentration in an aqueous medium upon mixing with a bolus of OMBs. Our results indicate that a 50 vol % OMB dispersion releases more than 330 mg/L of oxygen, surpassing arterial oxygen levels, and that more than 95% of this oxygen is released within 30 s. The rate of oxygenation of the OMB dispersions was comparable to that of a bolus injection of oxygen-saturated water under sufficient agitation, indicating that convection in the aqueous medium is the limiting transport mechanism. However, the lipid shell had a measurable effect on the oxygen release rate, which correlated with its oxygen permeability. Increasing the stirring speed increased both oxygen release rate and total amount of oxygen released. Overall, this study elucidates the fundamental stability and mass transport properties of the OMB dispersions under practical stirring conditions.","PeriodicalId":50,"journal":{"name":"Langmuir","volume":"59 1 1","pages":""},"PeriodicalIF":3.7000,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Langmuir","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1021/acs.langmuir.4c04104","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}

引用次数: 0

Abstract

Lipid-coated oxygen microbubbles (OMBs) are being investigated for biomedical applications to alleviate hypoxia such as systemic oxygenation and image-guided radiosensitization therapy. Additionally, they hold potential for boarder application as oxygen carriers beyond the biomedical filed. Understanding the stability and oxygen release properties of OMBs in dynamic aqueous environments is critical for these applications. In this study, we found that OMBs composed of longer acyl chain phospholipids (DSPC and DBPC) were stable in storage for at least 1 week, unlike the shorter acyl chain phospholipid (DPPC). OMBs were also more stable with a diacyl PEG–PE emulsifier compared with single-chain PEG-40 stearate. Dilution of OMBs did not alter the average diameter. While previous studies have examined the theoretical and experimental aspects of oxygen release from OMBs under static conditions, quantitative evaluations of OMB dispersions under dynamic stirring conditions remain limited. Here, we introduce a novel oxygen measurement method that quantitatively tracks the transition of the dissolved oxygen concentration in an aqueous medium upon mixing with a bolus of OMBs. Our results indicate that a 50 vol % OMB dispersion releases more than 330 mg/L of oxygen, surpassing arterial oxygen levels, and that more than 95% of this oxygen is released within 30 s. The rate of oxygenation of the OMB dispersions was comparable to that of a bolus injection of oxygen-saturated water under sufficient agitation, indicating that convection in the aqueous medium is the limiting transport mechanism. However, the lipid shell had a measurable effect on the oxygen release rate, which correlated with its oxygen permeability. Increasing the stirring speed increased both oxygen release rate and total amount of oxygen released. Overall, this study elucidates the fundamental stability and mass transport properties of the OMB dispersions under practical stirring conditions.

Abstract Image

查看原文本刊更多论文

求助全文

约1分钟内获得全文求助全文

来源期刊

Langmuir 化学-材料科学：综合

CiteScore

6.50

自引率

10.30%

发文量

1464

审稿时长

2.1 months

期刊介绍： Langmuir is an interdisciplinary journal publishing articles in the following subject categories: Colloids: surfactants and self-assembly, dispersions, emulsions, foams Interfaces: adsorption, reactions, films, forces Biological Interfaces: biocolloids, biomolecular and biomimetic materials Materials: nano- and mesostructured materials, polymers, gels, liquid crystals Electrochemistry: interfacial charge transfer, charge transport, electrocatalysis, electrokinetic phenomena, bioelectrochemistry Devices and Applications: sensors, fluidics, patterning, catalysis, photonic crystals However, when high-impact, original work is submitted that does not fit within the above categories, decisions to accept or decline such papers will be based on one criteria: What Would Irving Do? Langmuir ranks #2 in citations out of 136 journals in the category of Physical Chemistry with 113,157 total citations. The journal received an Impact Factor of 4.384*. This journal is also indexed in the categories of Materials Science (ranked #1) and Multidisciplinary Chemistry (ranked #5).