Umeå University's logo

umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Development of Next-Generation Optical Tweezers: The New Swiss Army Knife of Biophysical and Biomechanical Research
Umeå University, Faculty of Science and Technology, Department of Physics. (The BioPhysics & BioPhotonics group)ORCID iD: 0000-0002-1303-0327
2020 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

In a time when microorganisms are controlling the world, research in biology is more relevant than ever and this requires some powerful instruments. Optical tweezers use a focused laser beam to manipulate and probe objects on the nano- and microscale. This allows for the exploration of a miniature world at the border between biology, chemistry and physics. New methods for biophysical and physicochemical measurements are continuously being developed and at Umeå University there is a need for a new system that combines several of these methods. This would truly be the new Swiss army knife of biophysical and biomechanical research, extending their reach in the world of optical tweezing. My ambition with this project is to design and construct a robust system that incorporates optical trapping with high-precision force measurements and Raman spectroscopy, as well as introducing the possibility of generating multiple traps by using a spatial light modulator (SLM).

The proposed design incorporates four different lasers and a novel combination of signal detection techniques. To allow for precise control of the systems components and laser beams, I designed and constructed motorized opto-mechanical components. These are controlled by an in-house developed software that handles data processing and signal analysis, while also providing a user interface for the system. The components include, motorized beam blockers and optical attenuators, which were developed using commonly available 3D printing techniques and electronic controllers. By designing the system from scratch, I could eliminate the known weaknesses of conventional systems and allow for a modular design where components can be added easily. The system is divided into two parts, a laser breadboard and a main breadboard. The former contains all the equipment needed to generate and control the laser beams, which are then coupled through optical fibers to the latter. This contains the components needed to move the optical trap inside the sample chamber, while performing measurements and providing user feedback. Construction and testing was done for one sub-system at a time, while the lack of time required a postponement for the implementation of Raman and SLM.

The system performance was verified through Allan variance stability tests and the results were compared with other optical tweezers setups. The results show that the system follows the thermal limit for averaging times (τ) up to ~1 s when disturbances had been eliminated, which is similar to other systems. However, we could also show a decrease in variance all the way to τ = 2000 s, which is exceptionally good and not found in conventional systems. The force-resolution was determined to be on the order of femtonewtons, which is also exceptionally good. Thus, I conclude that this optical tweezers setup could lie as a solid foundation for future development and research in biological science at Umeå University for years to come.

Place, publisher, year, edition, pages
2020. , p. 43
Keywords [en]
optical tweezers, optical fiber tweezers, optical fiber, optical trapping, manipulation, optical force, cell trapping, biophysical, physicochemical, biomechanical, research, next-generation, raman spectroscopy, holographic optical tweezers
National Category
Medical Laboratory and Measurements Technologies Biochemistry and Molecular Biology Atom and Molecular Physics and Optics Physical Chemistry
Identifiers
URN: urn:nbn:se:umu:diva-172362OAI: oai:DiVA.org:umu-172362DiVA, id: diva2:1443415
Subject / course
Examensarbete i teknisk fysik
Educational program
Master of Science Programme in Engineering Physics
Presentation
2020-06-08, Institutionen för Fysik, Linneaus väg 20, Umeå, 10:00 (English)
Supervisors
Examiners
Available from: 2020-06-25 Created: 2020-06-18 Last updated: 2021-09-08Bibliographically approved

Open Access in DiVA

fulltext(21637 kB)2060 downloads
File information
File name FULLTEXT01.pdfFile size 21637 kBChecksum SHA-512
82c9be4187a997f0f8ac2f2b1391aabbf3a8a79e06b9d0291585a28415017544c09e2ccf0bff1f8a61d30a6452925b3081969263d881e07291e54f8f91485366
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Nilsson, Daniel
By organisation
Department of Physics
Medical Laboratory and Measurements TechnologiesBiochemistry and Molecular BiologyAtom and Molecular Physics and OpticsPhysical Chemistry

Search outside of DiVA

GoogleGoogle Scholar
Total: 2061 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 2272 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf