Biophotonics Lecture 1 PDF

 This course presented by Ass. Prof. Dr. Shaimaa Moustafa Alexeree Outline  What is the Biophotonics?  Structural of Biological Cells and Tissues.  Fundamental of light Matter Interaction.  Principles and Techniques (Photodynamic Therapy & Photothermal Therap...

 This course presented by Ass. Prof. Dr. Shaimaa Moustafa Alexeree Outline  What is the Biophotonics?  Structural of Biological Cells and Tissues.  Fundamental of light Matter Interaction.  Principles and Techniques (Photodynamic Therapy & Photothermal Therapy).  Bioimaging  Applications  Optical Biosensors  What is Biophotonics? * Three definitions of Biophotonics among many others: 1. Biophotonics is a multidisciplinary field that deals with all aspects of the interactions between light and biological material. Biophotonics is used in BIOLOGY to probe for molecular mechanisms, function, and structure. It is used in MEDICINE to study tissue and blood at the macro (large- scale) and micro (very small-scale) organism level to detect, diagnose, and treat diseases in a way that is non-invasive to the body. T. Husser IEEE-LEOS 2004 2. Interdisciplinary science studying the interaction of light with biological material – where “light” includes all forms of radiant energy whose quantum unit is the photon. D. Matthews, Optik & Photonik June 2007 No. 2 3. Applying light and other forms of radiant energy to the life sciences. Trieste, 2008 Interaction of light with biomaterials Introduction to Biophotonics Biophotonics involves all aspects of light-tissue interaction Introduction to Biophotonics  Introduction to Biophotonics Fig. 2. Biophotonics draws from the resources of many technical fields  Biophotonics  The technologies supporting biophotonics include optical fibers, optical sources and photodetectors, test and measurement instrumentation, nanotechnology, microscopy, spectroscopy, and miniaturization methodologies.  Therefore, biophotonics combines various optical methods to investigate the structural, functional, mechanical, biological, and chemical properties of biological materials and systems.  The wavelengths used for biophotonics typically range from 190 nm in the ultraviolet to 10.6 μm in the infrared region, with numerous applications being in the visible 400–700 nm spectrum. Thus a broad range of diverse tools and techniques are employed in biophotonics.  Biophotonics  Several terms are commonly used when studying the characteristics of biological matter includes:- 1) In vivo: The term in vivo (Latin for “in the living”) refers to tests or procedures on isolated biological components within whole, living organisms such as animals, humans, or plants. Such tests allow the observation of the condition, the temporal changes, or the effects of an experiment on biological components within a living entity in its natural surroundings. 2) In vitro: The term in vitro (Latin for “within the glass”) refers to tests done in a laboratory setting on biological components that have been extracted from a living organism. These tests are often made using containers such as glass test tubes, flasks, and petri dishes. Thus the evaluations are done on microorganisms, cells, molecules, or tissue samples outside of their normal biological environment. 3) Ex vivo: The term ex vivo (Latin for “from the living”) refers to procedures that typically involve taking living cells, tissues, or an organ from an organism and examining, modifying, or repairing these biological components in a controlled environment under sterile conditions with minimal alteration of the natural  Biophotonics Fig. 1.4 Applications of biophotonics tools and techniques  Biophotonics  Biophotonics offers challenging opportunities for researchers.  A fundamental understanding of the light activation of biomolecules and bioassemblies, and the subsequent photoinduced processes, is a fundamental requirement in designing new probes and drug delivery systems.  Also, an understanding of multiphoton processes utilizing ultra short laser pulses is a necessity both for developing new probes and creating new modalities of light-activated therapy. Some of the opportunities, categorized by discipline, are listed below: Chemists  Development of new fluorescent tags  Chemical probes for analyte detection and biosensing  Nanoclinics for targeted therapy  Nanochemistries for materials probes and nanodevices  New structures for optical activation  Biophotonics Biomedical Researchers  Bioimaging to probe molecular, cellular, and tissue functions  Optical signature for early detection of infectious diseases and cancers  Dynamic imaging for physiological response to therapy and drug delivery  Cellular mechanisms of drug action  Toxicity of photoactivatable materials  Biocompatibility of implants and probes Clinicians  In vivo imaging studies using human subjects  Development of optical in vivo probes for infections and cancers  In vivo optical biopsy and optical mammography  Tissue welding, contouring, and regeneration  Real-time monitoring of drug delivery and action  Long-term clinical studies of side effects  Biophotonics Physicists  Photoprocesses in biomolecules and bioassemblies  New physical principles for imaging and biosensing  Single-molecule biophysics  Nonlinear optical processes for diagnostics and therapy Engineers  Efficient and compact integration of new generation lasers, delivery systems, detectors  Device miniaturization, automation, and robotic control  New approaches to noninvasive or minimally invasive light activation  Optical engineering for in vivo imaging and optical biopsies  Nanotechnologies for targeted detection and activation  Optical BioMEMS (micro-electro-mechanical systems) and their nanoscale analogues. Biophotonics Spectral Windows  Biophotonics Spectral Windows ❖ Light propagates in the form of electromagnetic waves. In free space, light travels at a constant speed c = 299,792,458 m/s (or approximately 3 × 108 m/s). In biophotonics, the free-space speed of light could be expressed in units such as 30 cm/ns, 0.3 mm/ps, or 0.3 μm/fs. The speed of light in free space is related to the wavelength λ and the wave frequency ν through the equation. c = νλ. ❖ Upon entering a transparent or translucent dielectric medium or a biological tissue the light wave will travel at a slower speed s. The ratio between c and the speed s at which light travels in a material is called the refractive index (or index of refraction) n of the material (with n ≥ 1), so that s = c/n The higher the refractive index, the lower the velocity (Inverse relation).  Biophotonics Spectral Windows - Table 1. shows lists the indices of refraction for a variety of substances. Note that in many cases the refractive index changes with wavelength. ❑ Example 1.1 If a biological tissue sample has a refractive index n = 1.36, what is the speed of light in this medium? Solution: the speed of light in this tissue sample is  Biophotonics Spectral Windows  The ultraviolet (UV) region ranges from 10 to 400 nm, the visible spectrum runs from 400 nm violet to 700 nm red wavelengths, and the infrared (IR) region ranges from 700 nm to 300 μm.  Biophotonics disciplines are concerned mainly with wavelengths falling into the spectrum ranging from the mid-UV (about 190 nm) to the mid-IR (about 10 μm). Because optical properties vary from one tissue type to another, specific light wave windows are needed to carry out most therapeutic and diagnostic biophotonics processes. Thus, knowing the details of these properties allows the specification and selection of photonics components that meet the criteria for carrying out a biological process in a selected optical wavelength band.  Also shown in the following Figure is the relationship between the energy of a photon and its frequency (or wavelength), which is determined by the equation known as Planck’s Law. where the parameter h = 6.63 × 10-34 Js = 4.14 × 10-15 eVs is Planck’s constant. The unit J means joules and the unit eV stands for electron volts. In terms of wavelength (measured in units of μm), the energy in electron volts is given by Biophotonics Spectral Windows  Biophotonics Spectral Windows Fig. 3. Location of the biophotonics discipline in the electromagnetic spectrum  Biophotonics Spectral Windows The range from far-infrared (IR) to vacuum ultraviolet (UV) is called the optic wave region. Figure 2. Electromagnetic spectrum and types of interaction with matter (UV – ultraviolet, EUV – extreme UV, VIS – visible, IR – infrared, MW – microwaves, THz – terahertz, RW – radio waves).  Biophotonics Spectral Windows ❖ Table 2. Wavelength and photon energy ranges for various optical spectrum bands (Spectral band ranges are based on Document ISO-21348 of the International Standards Organization) ❖ Light interaction with tissues, produced:- “photophysical, photochemical, or photobiological effects” depend on “ energy density and/or power density” that are provided within the target area Different Light Sources References 1. N.H. Niemz, Laser-Tissue Interaction, 3rd edn. (Springer, 2007) 2. L.V. Wang, H.I. Wu, Biomedical Optics: Principles and Imaging (Wiley, Hoboken, NJ, 2007) 3. L. Pavesi, P.M. Fauchet (eds.), Biophotonics (Springer, 2008) 4. J. Popp, V.V. Tuchin, A. Chiou, S.H. Heinemann (eds.), Handbook of Biophotonics: Vol. 1: Basics and Techniques (Wiley, 2011) 5. J. Popp, V.V. Tuchin, A. Chiou, S.H. Heinemann (eds.), Handbook of Biophotonics: Vol. 2: Photonics for Healthcare (Wiley, 2011) 6. A.J. Welch, M.J.C. van Gemert (eds.), Optical-Thermal Response of Laser-Irradiated Tissue, 2nd edn. (Springer, 2011) 7. S.L. Jacques, Optical properties of biological tissues: a review. Phys. Med. Biol. 58, R37–R61 (2013) 8. T. Vo-Dinh (ed.), Biomedical Photonics Handbook, Vol. I-III, 2nd edn. (CRC Press, Boca Raton, FL, 2014) 9. K. Kulikov, Laser Interaction with Biological Material (Springer, 2014) 10. K. Tsia, Understanding Biophotonics (Pan Stanford Publishing, Singapore, 2015) 11. M. Olivo, U.S. Dinish (eds.), Frontiers in Biophotonics for Translational Medicine (Springer, Singapore, 2016) 12. A.H.-P. Ho, D. Kim, M.G. Somekh (eds.), Handbook of Photonics for Biomedical Engineering (Springer, 2016) 13. A. Kishen, A. Asundi, Fundamentals and Applications of Biophotonics in Dentistry (Imperial College Press, 2008)  References 14. H. Zhu, S.O. Isikman, O. Mudanyali, A. Greenbaum, A. Ozcan, Optical imaging techniques for point-of-care diagnostics. Lab Chip 13(1), 51–67 (7 Jan 2013). 15. M.W. Collins, C.S. König (eds.), Micro and Nano Flow Systems for Bioanalysis (Springer, New York, 2013) 16. A. Ricciardi, M. Consales, G. Quero, A. Crescitelli, E. Esposito, A. Cusano, Lab-on-fiber devices as an all around platform for sensing. Opt. Fiber Technol. 19(6), 772–784 (2013) 17. P. Vitruk, Oral soft tissue laser ablative and coagulative efficiencies spectra. Implant Practices 7(6), 23–27 (2014) 18. X. Yang, D. Lorenser, R.A. McLaughlin, R.W. Kirk, M. Edmond, M.C. Simpson, M.D. Grounds, D.D. Sampson, Imaging deep skeletal muscle structure using a high-sensitivity ultrathin side-viewing optical coherence tomography needle probe. Biomed. Opt. Express 5 (1), 136–148 (2014) 19. J. Albert, A lab on fiber. IEEE Spectr. 51, 48–53 (2014) 20. S.P. Morgan, B.C. Wilson, A. Vitkin, F.R.A.J. Rose, Optical Techniques in Regenerative Medicine (CRC Press, Boca Raton, FL, 2014) 21. S.A. Boppart, R. Richards-Kortum, Point-of-care and point-of-procedure optical imaging technologies for primary care and global health. Sci. Transl. Med. 6(253), article 253rv2 (Sept. 2014) [Review article] 22. F. Guarnieri (ed.), Corneal Biomechanics and Refractive Surgery (Springer, New York, 2015)