A comparative study of living cell micromechanical properties by oscillatory optical tweezers

Wei, Ming-Tzo; Zaorski, Angela; Yalcin, Huseyin C.; Wang, Jing; Ghadiali, Samir N.; Chiou, Arthur; Ou-Yang, H. Daniel

doi:10.1364/oe.16.008594

Cited by 88 publications

(72 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The penetration depth in all the experiments was smaller than 200 nm. Different methods have been proposed, in addition to atomic force microscopy, to extract the mechanical properties of cells, such as magnetic 31 and optical 32 tweezers, and micropipettes. 33 Generally, the methods and the procedures affect the final measure, giving different values for the mechanical stiffness for even the same cell.…”

Section: Effects Of Tnf-α Stimulation On the Apparent Elastic Modulusmentioning

confidence: 99%

Probing the mechanical properties of TNF-α stimulated endothelial cell with atomic force microscopy

Lee¹,

Zaske²,

Novellino³

et al. 2011

IJN

View full text Add to dashboard Cite

TNF-α (tumor necrosis factor-α) is a potent pro-inflammatory cytokine that regulates the permeability of blood and lymphatic vessels. The plasma concentration of TNF-α is elevated (> 1 pg/mL) in several pathologies, including rheumatoid arthritis, atherosclerosis, cancer, pre-eclampsia; in obese individuals; and in trauma patients. To test whether circulating TNF-α could induce similar alterations in different districts along the vascular system, three endothelial cell lines, namely HUVEC, HPMEC, and HCAEC, were characterized in terms of 1) mechanical properties, employing atomic force microscopy; 2) cytoskeletal organization, through fluorescence microscopy; and 3) membrane overexpression of adhesion molecules, employing ELISA and immunostaining. Upon stimulation with TNF-α (10 ng/mL for 20 h), for all three endothelial cells, the mechanical stiffness increased by about 50% with a mean apparent elastic modulus of E ~5 ± 0.5 kPa (~3.3 ± 0.35 kPa for the control cells); the density of F-actin filaments increased in the apical and median planes; and the ICAM-1 receptors were overexpressed compared with controls. Collectively, these results demonstrate that sufficiently high levels of circulating TNF-α have similar effects on different endothelial districts, and provide additional information for unraveling the possible correlations between circulating pro-inflammatory cytokines and systemic vascular dysfunction.

show abstract

Section: Effects Of Tnf-α Stimulation On the Apparent Elastic Modulusmentioning

confidence: 99%

Probing the mechanical properties of TNF-α stimulated endothelial cell with atomic force microscopy

Lee¹,

Zaske²,

Novellino³

et al. 2011

IJN

View full text Add to dashboard Cite

show abstract

“…The calibration of the spring constant k OT of the optical tweezers was done by oscillating a particle in water in the absence of DEP, and the phase of the displacement of the particle was used to determine the force constant of the trap. 4,7 Once the system is properly calibrated, we converted displacement readings in to absolute forces by Eq. ͑6a͒.…”

Section: Instrumentationmentioning

confidence: 99%

Direct measurements of the frequency-dependent dielectrophoresis force

Wei

Junio²,

Ou-Yang³

2009

Biomicrofluidics

Self Cite

View full text Add to dashboard Cite

Dielectrophoresis ͑DEP͒, the phenomenon of directed motion of electrically polarizable particles in a nonuniform electric field, is promising for applications in biochemical separation and filtration. For colloidal particles in suspension, the relaxation of the ionic species in the shear layer gives rise to a frequency-dependent, bidirectional DEP force in the radio frequency range. However, quantification methods of the DEP force on individual particles with the pico-Newton resolution required for the development of theories and design of device applications are lacking. We report the use of optical tweezers as a force sensor and a lock-in phase-sensitive technique for analysis of the particle motion in an amplitude modulated DEP force. The coherent detection and sensing scheme yielded not only unprecedented sensitivity for DEP force measurements, but also provided a selectivity that clearly distinguishes the pure DEP force from all the other forces in the system, including electrophoresis, electro-osmosis, heat-induced convection, and Brownian forces, all of which can hamper accurate measurements through other existing methods. Using optical tweezers-based force transducers already developed in our laboratory, we have results that quantify the frequency-dependent DEP force and the crossover frequency of individual particles with this new experimental method.

show abstract

“…C 12 E 6 C 12 E 6 C 12 E 6 20 wt% 50 wt% 80 wt% Table I. Viscosity of C 12 E 6 -water mixtures determined using the particle tracking and bulk measurements.…”

Section: 3mentioning

confidence: 99%

Mesoscopic Heterogeneity in Soft Materials by Local Rheological Measurements

Shundo

2017

J. Soc. Rheol., Jpn

View full text Add to dashboard Cite

Soft materials including polymers, micelles, gels and liquid crystals possess hierarchical structure with various length scales ranging from nanometer to micrometer. Thus, to give a better understanding of dynamics, it is necessary to examine the structure and physical properties at various length scales, and clarify the correlation between them. Recently, measurements of local rheological properties in soft materials have become possible with the advent of various techniques, called microrheology. In these techniques, rheological information can be accessed on the basis of the movement of probe particles dispersed in a sample to be measured. We have made an effort for time-and spatialresolved rheological measurements for soft materials, by using optical tweezers and particle tracking that fall under active and passive methods in microrheology, respectively. Such studies can provide information on a concentration fluctuation and a spatial heterogeneity in the systems. Notably, a worm-like micelle solution, a supramolecular hydrogel and lyotropic liquid crystals were spatially heterogeneous on the comparable or at a smaller length scale less than the characteristic length of network and interfacial structures, and on the time scale shorter than the relaxation time.

show abstract

A comparative study of living cell micromechanical properties by oscillatory optical tweezers

Cited by 88 publications

References 21 publications

Probing the mechanical properties of TNF-α stimulated endothelial cell with atomic force microscopy

Probing the mechanical properties of TNF-α stimulated endothelial cell with atomic force microscopy

Direct measurements of the frequency-dependent dielectrophoresis force

Mesoscopic Heterogeneity in Soft Materials by Local Rheological Measurements

Contact Info

Product

Resources

About

A comparative study of living cell micromechanical properties by oscillatory optical tweezers

Cited by 88 publications

References 21 publications

Probing the mechanical properties of TNF-&alpha; stimulated endothelial cell with atomic force microscopy

Probing the mechanical properties of TNF-&alpha; stimulated endothelial cell with atomic force microscopy

Direct measurements of the frequency-dependent dielectrophoresis force

Mesoscopic Heterogeneity in Soft Materials by Local Rheological Measurements

Contact Info

Product

Resources

About

Probing the mechanical properties of TNF-α stimulated endothelial cell with atomic force microscopy

Probing the mechanical properties of TNF-α stimulated endothelial cell with atomic force microscopy