Thermally responsive phospholipid preparations for fluid steering and separation in microfluidics
Xingwei Wu1, Ted J Langan, Brandon C Durney
1C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV 26506, USA.
Electrophoresis
|September 12, 2012
Summary
Aqueous phospholipid preparations exhibit shear-thinning properties, enabling effective fluid steering and sample delivery in microfluidic chips. These materials also function as both valving and separation media for biological applications.
Area of Science:
- Biomaterials Science
- Physical Chemistry
- Microfluidics
Background:
- Aqueous phospholipid preparations, specifically 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC), are widely used in biological studies.
- These phospholipid mixtures transition to a gel-like state near physiological temperatures but exhibit low viscosity below 24°C.
Purpose of the Study:
- To characterize the rheological properties of specific phospholipid preparations under conditions relevant to microfluidic applications.
- To evaluate the utility of these phospholipid preparations as functional components within microfluidic systems for fluid steering, sample delivery, and separation.
Main Methods:
- Rheological analysis of 20% phospholipid preparations with a DMPC/DHPC ratio of 2.5.
- Investigation of fluid behavior under conditions simulating microfluidic fluid steering.
- Demonstration of phospholipid integration as a valving and separation medium in a microfluidic chip.
Main Results:
- The phospholipid preparations were identified as shear-thinning power-law fluids, with a power-law index between 0.30 and 0.90 under tested conditions.
- The materials effectively steered fluids within microfluidic chips and facilitated hydrodynamic sample delivery.
- Successful separation of labeled linear oligosaccharides demonstrated the dual functionality of phospholipids as valving and separation media.
Conclusions:
- Phospholipid preparations exhibit advantageous rheological properties for microfluidic fluid control.
- These materials are versatile, serving as both active valving components and separation media in microfluidic devices.
- The findings support the use of these phospholipid systems for advanced sample handling and analysis in microfluidic platforms.
Related Concept Videos
01:23Membrane Fluidity
Cell membranes are composed of phospholipids, proteins, and carbohydrates loosely attached to one another through chemical interactions. Molecules are generally able to move about in the plane of the membrane, giving the membrane its flexible nature called fluidity. Two other features of the membrane contribute to membrane fluidity: the chemical structure of the phospholipids and the presence of cholesterol in the membrane.
01:26Membrane Fluidity
Membrane fluidity is explained by the fluid mosaic model of the cell membrane, which describes the plasma membrane structure as a mosaic of components—including phospholipids, cholesterol, proteins, and carbohydrates—that gives the membrane a fluid character.
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is a relatively...
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is a relatively...