Liquid interface tilt angle under thermal gradient: the surface-tension temperature coefficient

1991 ◽  
Vol 3 (25) ◽  
pp. 4743-4746
Author(s):  
M Papoular ◽  
J Amrit
Keyword(s):  
Surface Tension ◽  
Temperature Coefficient ◽  
Tilt Angle ◽  
Thermal Gradient ◽  
Liquid Interface

Tracing surfactant transformation from cellular release to insertion into an air-liquid interface

2004 ◽  
Vol 286 (5) ◽  
pp. L1009-L1015 ◽  
Author(s):  
T. Haller ◽  
P. Dietl ◽  
H. Stockner ◽  
M. Frick ◽  
N. Mair ◽  
...  
Keyword(s):  
Surface Tension ◽  
Cultured Cells ◽  
High Surface ◽  
Lamellar Body ◽  
Liquid Interface ◽  
Alveolar Type ◽  
Tensile Forces ◽  
Modify Surface ◽  
Fluorescence Imaging Microscopy ◽  
Air Liquid Interface

Pulmonary surfactant is secreted by alveolar type II cells as lipid-rich, densely packed lamellar body-like particles (LBPs). The particulate nature of released LBPs might be the result of structural and/or thermodynamic forces. Thus mechanisms must exist that promote their transformation into functional units. To further define these mechanisms, we developed methods to follow LBPs from their release by cultured cells to insertion in an air-liquid interface. When released, LBPs underwent structural transformation, but did not disperse, and typically preserved a spherical appearance for days. Nevertheless, they were able to modify surface tension and exhibited high surface activity when measured with a capillary surfactometer. When LBPs inserted in an air-liquid interface were analyzed by fluorescence imaging microscopy, they showed remarkable structural transformations. These events were instantaneous but came to a halt when the interface was already occupied by previously transformed material or when surface tension was already low. These results suggest that the driving force for LBP transformation is determined by cohesive and tensile forces acting on these particles. They further suggest that transformation of LBPs is a self-regulated interfacial process that most likely does not require structural intermediates or enzymatic activation.

scholarly journals Non-equilibrium surface tension of the vapour-liquid interface of active Lennard-Jones particles

2017 ◽  
Vol 147 (8) ◽  
pp. 084902 ◽  
Author(s):  
Siddharth Paliwal ◽  
Vasileios Prymidis ◽  
Laura Filion ◽  
Marjolein Dijkstra
Keyword(s):  
Surface Tension ◽  
Liquid Interface ◽  
Equilibrium Surface ◽  
Lennard Jones ◽  
Equilibrium Surface Tension ◽  
Non Equilibrium

Effects of surface tension and intraluminal fluid on mechanics of small airways

1997 ◽  
Vol 82 (1) ◽  
pp. 233-239 ◽  
Author(s):  
Mark J. Hill ◽  
Theodore A. Wilson ◽  
Rodney K. Lambert
Keyword(s):  
Surface Tension ◽  
Bending Stiffness ◽  
Liquid Interface ◽  
Cross Sectional Area ◽  
Pressure Curve ◽  
Small Airways ◽  
Sectional Area ◽  
Cross Sectional ◽  
Inner Surface ◽  
Air Liquid Interface

Hill, Mark J., Theodore A. Wilson, and Rodney K. Lambert.Effects of surface tension and intraluminal fluid on the mechanics of small airways. J. Appl. Physiol.82(1): 233–239, 1997.—Airway constriction is accompanied by folding of the mucosa to form ridges that run axially along the inner surface of the airways. The muscosa has been modeled (R. K. Lambert. J. Appl. Physiol. 71: 666–673, 1991) as a thin elastic layer with a finite bending stiffness, and the contribution of its bending stiffness to airway elastance has been computed. In this study, we extend that work by including surface tension and intraluminal fluid in the model. With surface tension, the pressure on the inner surface of the elastic mucosa is modified by the pressure difference across the air-liquid interface. As folds form in the mucosa, intraluminal fluid collects in pools in the depressions formed by the folds, and the curvature of the air-liquid interface becomes nonuniform. If the amount of intraluminal fluid is small, <2% of luminal volume, the pools of intraluminal fluid are small, the air-liquid interface nearly coincides with the surface of the mucosa, and the area of the air-liquid interface remains constant as airway cross-sectional area decreases. In that case, surface energy is independent of airway area, and surface tension has no effect on airway mechanics. If the amount of intraluminal fluid is >2%, the area of the air-liquid interface decreases as airway cross-sectional area decreases, and surface tension contributes to airway compression. The model predicts that surface tension plus intraluminal fluid can cause an instability in the area-pressure curve of small airways. This instability provides a mechanism for abrupt airway closure and abrupt reopening at a higher opening pressure.

Picoliter liquid handling at gas/liquid interface by surface and geometry control in a micro-nanofluidic device

2021 ◽  
Author(s):  
Kyojiro Morikawa ◽  
Shin-ichi Murata ◽  
Y Kazoe ◽  
Kazuma Mawatari ◽  
Takehiko Kitamori
Keyword(s):  
Surface Tension ◽  
Single Cell ◽  
Single Cell Analysis ◽  
Cell Lysis ◽  
Fused Silica ◽  
Liquid Interface ◽  
Nanofluidic Devices ◽  
Fluidic Control ◽  
Lysis Buffer ◽  
Nanofluidic Device

Abstract In micro- and nanofluidic devices, highly precise fluidic control is essential. Conventional mechanical valves in microchannels and nanochannels have size limitations, whereas hydrophobic (Laplace) valves are generally difficult to use for low-surface-tension liquids. In the present study, we developed a method for handling picoliter volumes of low-surface-tension liquids in a micro-nanofluidic device. The proposed Laplace valve is based on the pinning effect. A fused silica micro-nanofluidic device that includes a picoliter chamber whose geometry was designed to induce capillary pinning was designed and fabricated. The measured Laplace pressure of a lysis buffer (surfactant) was consistent with the calculated pressure, indicating successful fabrication and hydrophobic surface modification. The working principle of the Laplace valve was verified. The Laplace valve maintained the lysis buffer at the gas/liquid interface for 60 min, which is sufficiently long for cell lysis operations. Finally, replacement of liquids in the picoliter chamber using the valve was demonstrated. The proposed method will contribute to basic technologies for fluidic control in micro- and nanofluidic devices, and the proposed Laplace valve can be used for low-surface-tension liquids. In addition, the developed valve and picoliter chamber can be utilized for the interface in single-cell lysis, which will facilitate the development of single-cell analysis devices.

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