Chemiluminescence
Joy Harnish
Partner: Clinton Foriska
Synthesis and Chemiluminescence of Luminol
November 4, 2014
Abstract
Chemiluminescence occurs in nature and can be found in everyday products. For example, the light omitted by fireflies, deep sea fish and glow sticks is a result of this process. Luminol was synthesized from 3-nitrophthalic acid and then combined with potassium hexacyanoferrate(III) and hydrogen peroxide to omit a blue light. The product of this reaction is very unstable and is made by losing nitrogen and the electrons go from an excited state to ground state and the energy is emitted as a photon creating the blue light. After synthesizing the luminol, the chemiluminescence reaction is observed with and without quenchers, which deactivate the donor triplet and emit photons of different wavelengths. The results of luminol alone produced luminescence that lasted 11.89s. Fluorescein quencher resulted with a time of 9.59s, dichlorofluroescein quencher had a time of 8.86s and phenolphthalein quencher had the shortest time of 8.26s.
Introduction
Chemiluminescence reactions release energy in the form of light. Living organisms possess the ability to emit light by bioluminescence which is associated with vision, defense, prey and mate attraction. Chemiluminescence is a reaction in which a molecule absorbs energy and an electron is excited to the lowest unoccupied molecular orbital, and retains its spin value. This singlet excited state easily returns to the ground state by emitting the absorbed energy as a photon and is known as florescence. A singlet may undergo a change in spin, where both electrons have the same spin and creates a triplet excited state. This is called intersystem crossing and have longer lifetimes because the electrons are not spin-paired. Phosphorescence occurs when a triplet excited state returns to a singlet excited state and then easily returns to ground state. Triplet excited states can also serve as a donor and
Partner: Clinton Foriska
Synthesis and Chemiluminescence of Luminol
November 4, 2014
Abstract
Chemiluminescence occurs in nature and can be found in everyday products. For example, the light omitted by fireflies, deep sea fish and glow sticks is a result of this process. Luminol was synthesized from 3-nitrophthalic acid and then combined with potassium hexacyanoferrate(III) and hydrogen peroxide to omit a blue light. The product of this reaction is very unstable and is made by losing nitrogen and the electrons go from an excited state to ground state and the energy is emitted as a photon creating the blue light. After synthesizing the luminol, the chemiluminescence reaction is observed with and without quenchers, which deactivate the donor triplet and emit photons of different wavelengths. The results of luminol alone produced luminescence that lasted 11.89s. Fluorescein quencher resulted with a time of 9.59s, dichlorofluroescein quencher had a time of 8.86s and phenolphthalein quencher had the shortest time of 8.26s.
Introduction
Chemiluminescence reactions release energy in the form of light. Living organisms possess the ability to emit light by bioluminescence which is associated with vision, defense, prey and mate attraction. Chemiluminescence is a reaction in which a molecule absorbs energy and an electron is excited to the lowest unoccupied molecular orbital, and retains its spin value. This singlet excited state easily returns to the ground state by emitting the absorbed energy as a photon and is known as florescence. A singlet may undergo a change in spin, where both electrons have the same spin and creates a triplet excited state. This is called intersystem crossing and have longer lifetimes because the electrons are not spin-paired. Phosphorescence occurs when a triplet excited state returns to a singlet excited state and then easily returns to ground state. Triplet excited states can also serve as a donor and