Refractive index measurements of single, spherical cells using digital holographic microscopy

Mirjam Schürmann, Jana Scholze, Paul Müller, Chii J. Chan, Andrew Ekpenyong, Kevin J. Chalut, Jochen Guck

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

In this chapter, we introduce digital holographic microscopy (DHM) as a marker-free method to determine the refractive index of single, spherical cells in suspension. The refractive index is a conclusive measure in a biological context. Cell conditions, such as differentiation or infection, are known to yield significant changes in the refractive index. Furthermore, the refractive index of biological tissue determines the way it interacts with light. Besides the biological relevance of this interaction in the retina, a lot of methods used in biology, including microscopy, rely on light-tissue or light-cell interactions. Hence, determining the refractive index of cells using DHM is valuable in many biological applications. This chapter covers the main topics that are important for the implementation of DHM: setup, sample preparation, and analysis. First, the optical setup is described in detail including notes and suggestions for the implementation. Following that, a protocol for the sample and measurement preparation is explained. In the analysis section, an algorithm for the determination of quantitative phase maps is described. Subsequently, all intermediate steps for the calculation of the refractive index of suspended cells are presented, exploiting their spherical shape. In the last section, a discussion of possible extensions to the setup, further measurement configurations, and additional analysis methods are given. Throughout this chapter, we describe a simple, robust, and thus easily reproducible implementation of DHM. The different possibilities for extensions show the diverse fields of application for this technique.

Original languageEnglish
Pages (from-to)143-159
Number of pages17
JournalMethods in Cell Biology
Volume125
DOIs
StatePublished - 2015

Fingerprint

Refractometry
Microscopy
Light
Cell Communication
Retina
Suspensions
Infection

All Science Journal Classification (ASJC) codes

  • Cell Biology
  • Medicine(all)

Cite this

Refractive index measurements of single, spherical cells using digital holographic microscopy. / Schürmann, Mirjam; Scholze, Jana; Müller, Paul; Chan, Chii J.; Ekpenyong, Andrew; Chalut, Kevin J.; Guck, Jochen.

In: Methods in Cell Biology, Vol. 125, 2015, p. 143-159.

Research output: Contribution to journalArticle

Schürmann, Mirjam ; Scholze, Jana ; Müller, Paul ; Chan, Chii J. ; Ekpenyong, Andrew ; Chalut, Kevin J. ; Guck, Jochen. / Refractive index measurements of single, spherical cells using digital holographic microscopy. In: Methods in Cell Biology. 2015 ; Vol. 125. pp. 143-159.
@article{15694c5ec3184958bb8a87169c9fee35,
title = "Refractive index measurements of single, spherical cells using digital holographic microscopy",
abstract = "In this chapter, we introduce digital holographic microscopy (DHM) as a marker-free method to determine the refractive index of single, spherical cells in suspension. The refractive index is a conclusive measure in a biological context. Cell conditions, such as differentiation or infection, are known to yield significant changes in the refractive index. Furthermore, the refractive index of biological tissue determines the way it interacts with light. Besides the biological relevance of this interaction in the retina, a lot of methods used in biology, including microscopy, rely on light-tissue or light-cell interactions. Hence, determining the refractive index of cells using DHM is valuable in many biological applications. This chapter covers the main topics that are important for the implementation of DHM: setup, sample preparation, and analysis. First, the optical setup is described in detail including notes and suggestions for the implementation. Following that, a protocol for the sample and measurement preparation is explained. In the analysis section, an algorithm for the determination of quantitative phase maps is described. Subsequently, all intermediate steps for the calculation of the refractive index of suspended cells are presented, exploiting their spherical shape. In the last section, a discussion of possible extensions to the setup, further measurement configurations, and additional analysis methods are given. Throughout this chapter, we describe a simple, robust, and thus easily reproducible implementation of DHM. The different possibilities for extensions show the diverse fields of application for this technique.",
author = "Mirjam Sch{\"u}rmann and Jana Scholze and Paul M{\"u}ller and Chan, {Chii J.} and Andrew Ekpenyong and Chalut, {Kevin J.} and Jochen Guck",
year = "2015",
doi = "10.1016/bs.mcb.2014.10.016",
language = "English",
volume = "125",
pages = "143--159",
journal = "Methods in Cell Biology",
issn = "0091-679X",
publisher = "Academic Press Inc.",

}

TY - JOUR

T1 - Refractive index measurements of single, spherical cells using digital holographic microscopy

AU - Schürmann, Mirjam

AU - Scholze, Jana

AU - Müller, Paul

AU - Chan, Chii J.

AU - Ekpenyong, Andrew

AU - Chalut, Kevin J.

AU - Guck, Jochen

PY - 2015

Y1 - 2015

N2 - In this chapter, we introduce digital holographic microscopy (DHM) as a marker-free method to determine the refractive index of single, spherical cells in suspension. The refractive index is a conclusive measure in a biological context. Cell conditions, such as differentiation or infection, are known to yield significant changes in the refractive index. Furthermore, the refractive index of biological tissue determines the way it interacts with light. Besides the biological relevance of this interaction in the retina, a lot of methods used in biology, including microscopy, rely on light-tissue or light-cell interactions. Hence, determining the refractive index of cells using DHM is valuable in many biological applications. This chapter covers the main topics that are important for the implementation of DHM: setup, sample preparation, and analysis. First, the optical setup is described in detail including notes and suggestions for the implementation. Following that, a protocol for the sample and measurement preparation is explained. In the analysis section, an algorithm for the determination of quantitative phase maps is described. Subsequently, all intermediate steps for the calculation of the refractive index of suspended cells are presented, exploiting their spherical shape. In the last section, a discussion of possible extensions to the setup, further measurement configurations, and additional analysis methods are given. Throughout this chapter, we describe a simple, robust, and thus easily reproducible implementation of DHM. The different possibilities for extensions show the diverse fields of application for this technique.

AB - In this chapter, we introduce digital holographic microscopy (DHM) as a marker-free method to determine the refractive index of single, spherical cells in suspension. The refractive index is a conclusive measure in a biological context. Cell conditions, such as differentiation or infection, are known to yield significant changes in the refractive index. Furthermore, the refractive index of biological tissue determines the way it interacts with light. Besides the biological relevance of this interaction in the retina, a lot of methods used in biology, including microscopy, rely on light-tissue or light-cell interactions. Hence, determining the refractive index of cells using DHM is valuable in many biological applications. This chapter covers the main topics that are important for the implementation of DHM: setup, sample preparation, and analysis. First, the optical setup is described in detail including notes and suggestions for the implementation. Following that, a protocol for the sample and measurement preparation is explained. In the analysis section, an algorithm for the determination of quantitative phase maps is described. Subsequently, all intermediate steps for the calculation of the refractive index of suspended cells are presented, exploiting their spherical shape. In the last section, a discussion of possible extensions to the setup, further measurement configurations, and additional analysis methods are given. Throughout this chapter, we describe a simple, robust, and thus easily reproducible implementation of DHM. The different possibilities for extensions show the diverse fields of application for this technique.

UR - http://www.scopus.com/inward/record.url?scp=84921886073&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84921886073&partnerID=8YFLogxK

U2 - 10.1016/bs.mcb.2014.10.016

DO - 10.1016/bs.mcb.2014.10.016

M3 - Article

VL - 125

SP - 143

EP - 159

JO - Methods in Cell Biology

JF - Methods in Cell Biology

SN - 0091-679X

ER -