Quantifying Distance Dependent Perturbations of Fluorescent Lipids in a DPPC Bilayer with Molecular Dynamics

The interaction of unblocked glycine, lysine, proline and histidine with a DPPC bilayer was assessed using extensive atomistic molecular dynamics simulations.

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Molecular Dynamics Simulation of DPPC Bilayer in DMSO

Biophysical Journal ◽

10.1016/s0006-3495(99)77402-3 ◽

1999 ◽

Vol 76 (5) ◽

pp. 2472-2478 ◽

Cited By ~ 61

Author(s):

Alexander M. Smondyrev ◽

Max L. Berkowitz

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Dynamics Simulation ◽

Dppc Bilayer

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Structural perturbation of a dipalmitoylphosphatidylcholine (DPPC) bilayer by warfarin and its bolaamphiphilic analogue: A molecular dynamics study

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2016.01.056 ◽

2016 ◽

Vol 468 ◽

pp. 227-237 ◽

Cited By ~ 7

Author(s):

Manuela Aseye Ayele Ayee ◽

Charles William Roth ◽

Belinda Sena Akpa

Keyword(s):

Molecular Dynamics ◽

Structural Perturbation ◽

Dppc Bilayer

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Surface tension effects on the phase transition of a DPPC bilayer with and without protein: a molecular dynamics simulation

Physical Chemistry Chemical Physics ◽

10.1039/c3cp55524k ◽

2014 ◽

Vol 16 (18) ◽

pp. 8434-8440 ◽

Cited By ~ 7

Author(s):

Xian Kong ◽

Shanshan Qin ◽

Diannan Lu ◽

Zheng Liu

Keyword(s):

Phase Transition ◽

Molecular Dynamics ◽

Surface Tension ◽

Molecular Dynamics Simulation ◽

Protein A ◽

Dynamics Simulation ◽

Coarse Grained ◽

Surface Tensions ◽

Phase Transition Behavior ◽

Dppc Bilayer

A coarse-grained molecular dynamics simulation was applied to illustrate the phase transition behavior of the pure DPPC bilayer and aquaporin-embedded DPPC bilayer under different surface tensions.

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Molecular Dynamics Simulations of Dialkyl Carbocyanine Dyes in a DPPC Bilayer: Atomistic Insights Into Single Molecule Fluorescence

ASME 2007 Summer Bioengineering Conference ◽

10.1115/sbc2007-176614 ◽

2007 ◽

Author(s):

Ramachandra Gullapalli ◽

Melik Demirel ◽

Peter J. Butler

Keyword(s):

Molecular Dynamics ◽

Single Molecule ◽

Membrane Lipids ◽

Dynamics Simulation ◽

Spectroscopic Techniques ◽

Carbocyanine Dyes ◽

Lipid Dynamics ◽

Membrane Perturbation ◽

Dppc Bilayer ◽

Dynamics Simulations

Our group uses di-alkyl carbocyanine dyes to detect force-induced membrane perturbation in mechanotransduction studies (Butler et al 2000). These dyes are also used extensively in single molecule spectroscopic techniques to infer dynamics of native membrane lipids. However, the precise distribution and orientation of the dye in a bilayer and how well the dye dynamics mimic native lipid dynamics are not known. Thus we present the results of a 40 nanosecond molecular dynamics simulation of a fully hydrated bilayer containing 0, 2, or 4 molecules of 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (DiI-C18) and 128 molecules of dipalmitoylphosphatidyl choline (DPPC).

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Preserving the Integrity of Liposomes Prepared by Ethanol Injection upon Freeze-Drying: Insights from Combined Molecular Dynamics Simulations and Experimental Data

Pharmaceutics ◽

10.3390/pharmaceutics12060530 ◽

2020 ◽

Vol 12 (6) ◽

pp. 530 ◽

Cited By ~ 1

Author(s):

Silvia Franzè ◽

Francesca Selmin ◽

Paolo Rocco ◽

Giuseppe Colombo ◽

Antonella Casiraghi ◽

...

Keyword(s):

Molecular Dynamics ◽

Freeze Drying ◽

Md Simulations ◽

Vinyl Pyrrolidone ◽

Ethanol Injection ◽

Dppc Bilayer ◽

Liposome Size ◽

Poly Vinyl Pyrrolidone ◽

Dynamics Simulations ◽

Residual Organic Solvents

The freeze-drying of complex formulations, such as liposomes, is challenging, particularly if dispersions contain residual organic solvents. This work aimed to investigate the effects of possible protectants, namely sucrose, trehalose and/or poly(vinyl pyrrolidone) (PVP), on the main features of the dried product using a 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)-based liposomal dispersion prepared by ethanol injection and containing ethanol up to 6%, as a model. The interactions among vesicles and protectants were preliminary screened by Molecular Dynamics (MD) simulations, which have been proved useful in rationalizing the selection of protectant(s). The freeze-drying protocol was based on calorimetric results. Overall data suggested a stronger cryo-protectant effect of trehalose, compared with sucrose, due to stronger interactions with the DPPC bilayer and the formation of highly ordered clusters around the lipids. The effect further improved in the presence of PVP. Differently from the other tested protectants, the selected trehalose/PVP combination allows to preserve liposome size, even in the presence of 6% ethanol, as demonstrated by Nanoparticle Tracking Analysis (NTA). Nevertheless, it should be also underlined that cakes blew out at an ethanol concentration higher than 1% v/v, probably due to the poor cohesion within the cake and solvent vapour pressure upon sublimation.

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