Optical manipulation for single‐cell studies

Abstract

In the last decade optical manipulation has evolved from a field of interest for physicists to a versatile tool widely used within life sciences. This has been made possible in particular due to the development of a large variety of imaging techniques that allow detailed information to be gained from investigations of single cells. The use of multiple optical traps has high potential within single-cell analysis since parallel measurements provide good statistics. Multifunctional optical tweezers are, for instance, used to study cell heterogeneity in an ensemble, and force measurements are used to investigate the mechanical properties of individual cells. Investigations of molecular motors and forces on the single-molecule level have led to discoveries that would have been difficult to make with other techniques. Optical manipulation has prospects within the field of cell signalling and tissue engineering. When combined with microfluidic systems the chemical environment of cells can be precisely controlled. Hence the influence of pH, salt concentration, drugs and temperature can be investigated in real time. Fast advancing technical developments of automated and user-friendly optical manipulation tools and cross-disciplinary collaboration will contribute to the routinely use of optical manipulation techniques within the life sciences.

Hydrodynamic Cell Trapping for High Throughput Single-Cell Applications

“…Several other methods have also been coupled with microfluidics for cell immobilization and conducting controlled, complete cell assays. Flow-based active cell trapping by using control valves [14,15], non-invasive optical trapping [16][17][18], dielectrophoresis [19][20][21], surface chemistry modification techniques [22,23], arrays of physical barriers [24], cell trapping by negative pressure [25,26], and hydrodynamic methods [27][28][29] are some of these successfully established techniques.…”

Optical Tweezers: Autonomous Robots for the Manipulation of Biological Cells

“…Thus, γẋ represents the viscous drag force, ζΓ(t) models the thermal force arising from Brownian motion, and F ext encodes the external forces due to collisions, gravity, and buoyancy. The stochastic form of Γ(t) prevents a direct analytical solution of Equation (2). However, ζΓ(t) can be replaced by 2γk B T δt N (0, 1) to solve Equation (2) numerically in discrete time.…”

“…Optical tweezers (OT) is a popular tool for manipulating biological objects especially cells [1], [2]. Using a tightly focussed laser beam, it exerts sufficient forces to tweeze, i.e., hold (trap) and move, freely diffusing cells in the vicinity of the beam focus.…”

Polymer-Based Microfluidic Devices for Pharmacy, Biology and Tissue Engineering

“…This is especially important when applying optical tweezers. Many studies deal with the photoinduced effects caused by the trapping lasers, and for each new application, viability studies should be performed [357]. Acoustic methods for cell manipulation within microfluidic systems, such as using ultrasound, have been reported to be without significant effects on cell viability [358].…”