Chem ilum inescence

by Thomas Splietker Table of Content

 Historical Introduction

 Principle

 Applications  Glowsticks  Forensic  Detection of Biomolecules

 Special Cases  Bioluminescence  Electrochemiluminescence

18.06.2012 2 Thomas Splietker Historical Introduction

 1669 discovered by pharmacist and alchemist Heinrich Henning Brand in Hamburg

 The term „chemilumineszenz“ is charaterized by Eilhard Wiedemann in 1888

18.06.2012 3 Thomas Splietker Principle

[A] + [B] → [AB*] → [AB] + hν

 [A] Luminophore

 [B] TillTypically an oxidizi ng agent

 [AB*] Excited intermediate

 In reality, reactions are often more complex

They do not need an electrical power source!

18.06.2012 4 Thomas Splietker Applications

18.06.2012 Thomas Splietker Glowsticks

Glowsticks for partys, emergency lighting and fishing

 Plastic tubes filled with

a) Phenyloxalate

b) Dye

c) Glasstube filled with hdhydrogen peroxide

18.06.2012 6 Thomas Splietker Glowsticks

1) Oxidation of an diphenyl oxalate (top) 2) Decomposition of 1,2‐dioxetanedione (middle) 3) Relaxation of dye (lower)

18.06.2012 7 Thomas Splietker Examples for dyes (Fluoropp)hores) blue green yellow red 9,10‐diphenylanthracene 9,10‐bis(phenylethynyl) anthracene (5,6,11,12‐tetraphenyl naphthacene) Rhodamine B (DPA) (BPEA) (Rubrene) There are a lot of other possible dyes

18.06.2012 8 Thomas Splietker Applications

 Luminol* is used in forensics for blood detection

 Oxidation of luminol, in the presence of iron or manganese ions, through hydrogen peroxide

*5‐Amino‐2,3‐dihydro‐1,4‐phthalazinedione 18.06.2012 9 Thomas Splietker Detection of Biomolecules

 Common technique for a variety of detection assays in biology

 Principle: • Horseradhdish peroxidase enzym (HRP) is tethered to the molecule of interest • HRP catalyzes a substrate into a sensitized reagent which produces a triplet (excited) carbonyl through

oxidation (H2O2) • By decay to singlet carbonyl, light is emitted 18.06.2012 10 Thomas Splietker Special Bio ‐ &

Electrochemiluminescence

cases

18.06.2012 Thomas Splietker Bioluminescence

 Naturally occuring form of ccehemil umin esceceescence

 Creatures produce luciferin (pigment) and luciferase (enzyme)  Luciferin reacts with oxygen under light emission while luciferase acts as catalyst to speed up thereaction

 90% of deepsea organisms produce biol umi nescence

18.06.2012 12 Thomas Splietker Bioluminescence

Firefly luciferin Firefly luciferase (4S) ‐2‐(6‐hyyydroxy‐1,3‐benzothiazol‐2‐yy)l)‐4,5‐ Structure of Photinus pyralis firefly luciferase dihydrothiazole‐4‐carboxylic acid

18.06.2012 13 Thomas Splietker Electrochemiluminescence (ECL)

 Is based on electrochemical (redox‐) reactions in solutions:

• Electrochemically generated intermediates • Exergonic reaction produces an electronically excited state • Relaxation to a lower level state causes light emission

 Wavelength of of light corresponds to the energy gap between those states

 ECL is proved to be very useful in analytical applications

18.06.2012 14 Thomas Splietker Electrochemiluminescence (ECL)

18.06.2012 15 Thomas Splietker ECL detection of Biomolecules

18.06.2012 16 Thomas Splietker Conclusion & Outlook

 Only a small niche market:

• No huge impact in the lighting industry, only small special applications

• ECL seems not to be an alternative to OLEDs, relative low amount of papers published in last years

• Very successful and growing market in Biomolecul detection, a lot of new papers showing interest in optimization of this technique

18.06.2012 17 Thomas Splietker References

 http://elements.vanderkrogt.net/element.php?sym=P

 http://www.unitednuclear.com/blood.htm

 http://fuckyeahforensics.tumblr.com/post/6699082754/luminol‐is‐used‐by‐forensic‐investigators‐to

 Eilhard Wiedemann, Ueber Fluorescenz und Phosphorescenz I. Abhandlung. Annalen der Physik, 270,446–463 (1888). doi: 10.1002/andp.18882700703

 http://www.layoutsparks.com/1/228686/glowsticks‐multicolour‐variety‐image.html

 http://upload.wikimedia.org/wikipedia/commons/thumb/a/ad/Cyalume‐reactions.svg/1000px‐Cyalume‐reactions.svg.png

 hhtt//ttp://www.w ildbildabout tbitibritain.co.uk/ k/itpictures/d /dt//ata/2/medi um/ 1g.jpg

 http://en.wikipedia.org/wiki/Luciferase

 http://upload.wikimedia.org/wikipedia/commons/thumb/1/16/Firefly_luciferin.svg/500px‐Firefly_luciferin.svg.png

 http://www.meso‐scale.com/catalogsystemweb/webroot/images/technology/ecl_diagram.gif

 http://www.licor.com/bio/applications/odysseyFc_applications/images/westernBlottingIllo‐chemi.jpg

18.06.2012 18 Thomas Splietker Chem ilum ineszenz

by Thomas Splietker