Combining Digital Holographic Microscopy with Microfluidics: A New Tool in Biotechnology - Biomedical Optical Phase Microscopy and Nanoscopy - page 186

CHAPTER 10
Combining Digital Holographic Microscopy
with Microfluidics: A New Tool in
Biotechnology

Lisa Miccio 1 , Pasquale Memmolo 1 , Francesco Merola 1 , Melania Paturzo 1 ,
Roberto Puglisi 2 , Donatella Balduzzi 2 , Andrea Galli 2 , Pietro Ferraro 1
1

Istituto Nazionale di Ottica del CNR—UOS di Napoli, Pozzuoli (NA) Italy

2

Istituto Sperimentale Italiano “Lazzaro Spallanzani,” Localit ` La Quercia, Cremona, Italy

Editor: Zeev Zalevsky

10.1 Introduction

In recent years, biomicrofluidic technology has grown significantly [1,2] resulting in high
demand for advancements in multifunctional methods for observing processes, for their
characterization, and for manipulation of particles in microfluidic environments. Numerous
methods have been suggested and implemented for qualitative imaging, phase contrast
quantitative analysis [3 13] , handling and trapping [14 16] , and for the accurate tracking
of the paths of nano/microparticles (i.e., nanodrops, carbon nanotubes, biocells, quantum
dots, dielectric spheres, and for metallic spheres) in microfluidic lab-on-a-chip devices
[17 21] .

Optical tweezers have facilitated a rapid growth in particle manipulation approaches
[22 24] . Particles can be trapped or moved along certain trajectories or relocated by using
appropriate intensity field distribution of the single laser beam. Exploiting Gaussian or
Laguerre Gaussian laser beams modes, the particles can be induced to move in straight or
curved trajectories. Thanks to the advent of spatial light modulators, which work as
programmable diffraction optical elements, multiparticle trapping has become a reality
[24 26] . Optical tweezers allow the study of the properties of the fluid in which the beads
are embedded based on the dynamic position of the particle as it is driven along a definite
path. Some approaches exist for tracking single or multiple trapped particles [27 30] .
Numerous techniques achieve the tracking analysis with high accuracy using a single