Typical Optical Clearing Agents

  • Luís Manuel Couto Oliveira
  • Valery Victorovich Tuchin
Part of the SpringerBriefs in Physics book series (SpringerBriefs in Physics)


With the growing research in the field of optical clearing and the various applications of this technique that have been recently developed, more than 1000 agents have been tested in various tissues in the past two decades to evaluate their clearing potential. To optimize the clearing treatments, knowledge on the dispersions and absorption spectra of the agents is necessary. We have gathered experimental and literature data to show that the absorption bands of typical clearing agents are located in the deep ultraviolet range, where the refractive index is significantly high. The desired characteristics for the clearing agents are presented, and their classification in three major groups is indicated. Solutions containing mixtures of optical clearing agents (OCAs) and diluted solutions are also important for certain applications, such as the enhancement of agent delivery or the evaluation of agent diffusion properties. Such applications are referred, and some examples are presented. A simple method to prepare diluted solutions of clearing agents is also described.


Optical clearing agents Sugars Alcohols OCA absorption OCA dispersion Refractive index matching Solution preparation 


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Copyright information

© The Author(s), under exclusive license to Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Luís Manuel Couto Oliveira
    • 1
  • Valery Victorovich Tuchin
    • 2
    • 3
    • 4
    • 5
  1. 1.Physics Department and Center for Innovation in Engineering and Industrial TechnologyPolytechnic Institute of Porto – School of EngineeringPortoPortugal
  2. 2.Department of Optics and BiophotonicsSaratov State UniversitySaratovRussia
  3. 3.Institute of Precision Mechanics and Control of the RASSaratovRussia
  4. 4.Bach Institute of BiochemistryResearch Center of Biotechnology of the RASMoscowRussia
  5. 5.Tomsk State University, Tomsk & ITMO UniversitySt. PetersburgRussia

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