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Determination of the Main Phase Transition Temperature of Phospholipids by Nanoplasmonic Sensing.

ABSTRACT: Our study demonstrates that nanoplasmonic sensing (NPS) can be utilized for the determination of the phase transition temperature (T_m) of phospholipids. During the phase transition, the lipid bilayer undergoes a conformational change. Therefore, it is presumed that the T_m of phospholipids can be determined by detecting conformational changes in liposomes. The studied lipids included 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), and 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC). Liposomes in gel phase are immobilized onto silicon dioxide sensors and the sensor cell temperature is increased until passing the T_m of the lipid. The results show that, when the system temperature approaches the T_m, a drop of the NPS signal is observed. The breakpoints in the temperatures are 22.5?°C, 41.0?°C, and 55.5?°C for DMPC, DPPC, and DSPC, respectively. These values are very close to the theoretical T_m values, i.e., 24?°C, 41.4?°C, and 55?°C for DMPC, DPPC, and DSPC, respectively. Our studies prove that the NPS methodology is a simple and valuable tool for the determination of the T_m of phospholipids.

SUBMITTER: Chen W

PROVIDER: S-EPMC6172256 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Determination of the Main Phase Transition Temperature of Phospholipids by Nanoplasmonic Sensing.

Chen Wen W Duša Filip F Witos Joanna J Ruokonen Suvi-Katriina SK Wiedmer Susanne K SK

Scientific reports 20181004 1

Our study demonstrates that nanoplasmonic sensing (NPS) can be utilized for the determination of the phase transition temperature (T<sub>m</sub>) of phospholipids. During the phase transition, the lipid bilayer undergoes a conformational change. Therefore, it is presumed that the T<sub>m</sub> of phospholipids can be determined by detecting conformational changes in liposomes. The studied lipids included 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-dimyristoyl-sn-glycero-3-phosphochol ...[more]

PMID: 30287903

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Dataset Information

Determination of the Main Phase Transition Temperature of Phospholipids by Nanoplasmonic Sensing.

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Determination of the Main Phase Transition Temperature of Phospholipids by Nanoplasmonic Sensing.

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