Biophysics

Introduction  Def.: Biophysics (also biological physics) is an interdisciplinary science that applies the theories and methods of physics to questions of biology. interdisciplinarysciencephysics biology

Physical Machinery  Flow cytometry  Mass spectrometry  Atomic Force Microscopy  High Performance Liquid Chromatography/ Gas Chromatography

Flow cytometry – in general  Technique for counting, examining, and sorting microscopic particles  Allows for the analysis of several physical and chemical characteristics of single cellschemical  Characteristics:- Size of the cell - inner complexity of the particle - fluorochromes labled molecules charite.de

Fluorophor

Flow cytometry – Principle users.path.ox.ac.uk

1. Experiment Each group gets a funnel and counts how many orange counters they have. Several hundred cells per second + Analyse certain factors

Flow cytometry – Further performance  Allows specific cell sorting  By vibrating the stream  drops form  Induce an electrical pulse  charges the droplets  These are deflected in the electric field users.path.ox.ac.uk

Flow cytometry – Application?

Flow cytometry – Current research  Currently used as a common technique for medical diagnosis  They are used for analysis of bacterial ecology  In the future it is hoped that it will be useful in phytoplankton analysis

Mass spectrometry – in general  Analytical technique used to measure the mass-to-charge ratio of ion

2. Experiment 2 Volunteers a = F / m

Mass spectrometry – Principle 1. step 2. step3. step 1. Ionisation 2. Acceleration 3. Detection

Mass spectrometry – Principle  Some machines use different ionisation techniques: Electrospray ionization Matrix-assistant laser desorption/ionisation (MALDI) proteomesoftware.com wikipedia.com

Mass spectrometry – Application? medizinisches-proteom-center.de

Mass spectrometry – Current research  Analyse cell compounds  Identify unknown compounds by the mass of their molecules or of their fragments  Quantify the amount of a compound in a sample using carefully designed methods

Atomic Force Microscopy – The Basics  Scanning of a surface with a very small tip  The machine measures the surface structure and creates a profile bpe.tnw.utwente.nl

3. Experiment Each group will get 2 toothpicks 0.3 cm = 3mm = 3000µm = nm The AFM has a resolution of: Lateral – 5nm Vertical – 0.2nm

Atomic Force Microscopy – Principle  Angel change  Mesurement of the force on the tip at the surface  Determine the height of the surface point

Atomic Force Microscopy – Application? cp.home.agilent.com

Atomic Force Microscopy – Current research  Mostly used in engineering  Surface characterization e.g. lipid layer  Molecule-Receptor Interaction

Chromatography – An overview  Technique for the seperation of mixtures  Passing a mixture dissolved in a mobile phase through a stationary phase  Seperation is caused by differences in partitioning behavior of molecules between a mobile phase and a stationary phase

4. Experiment Make two lines and we need 2 Volunteers The more similarities the higher the interaction

5. Experiment Each group gets a paper towel and water dkimages.com We seperated the different fragments of the color

HPLC or GC  HPLC: (high pressure liquid chromatography)  GC: (gas chromatography)

Chromatography – Application? GCHPLC

Chromatography – Current research?  Determination of hormone levels  Drug testing e.g. Amphetamine  Doping tests e.g. Testosterone

Multiple-Choice An algae culture produces an interesting substance. We want to characterise it. Which machine would be the most useful? Flow cytometry HPLC/ GC Mass Spetrometry Atomic Force Microskopy

Multiple-Choice Leaves change their color during the year. Which machine would be useful to examine the pigment composition? Flow cytometry HPLC/ GC Mass Spetrometry Atomic Force Microskopy

Multiple-Choice Which machine could be used to examine the interaction between a signal molecule and a receptor? Flow cytometry HPLC/ GC Mass Spetrometry Atomic Force Microscopy

Multiple-Choice We want to quantify different types of cells in our blood. Which one would be useful? Flow cytometry HPLC/ GC Mass Spetrometry Atomic Force Microskopy

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