What is singlet oxygen generation?

Singlet oxygen is produced from a photosensitizer molecule reacting with ground state oxygen. Molecular triplet states are chemically reactive due to their long decay times and the presence of unpaired valence electrons. Reactivity with ground state oxygen (3O2) will yield singlet oxygen (1O2).

Which is photosensitizer?

Photosensitizers are molecules that can be activated by light in order to generate ROS that can damage cell structures from microorganisms or from diseased mammalian cells leading to cell death.

What is a photosensitizer in PDT?

In particular, in photodynamic therapy (PDT), a light-sensitive compound or structure, commonly named a photosensitizer (PS), is able to produce reactive oxygen species (ROS) after being irradiated with light in the presence of oxygen.

What is singlet oxygen quantum yield?

The singlet oxygen quantum yield is a quantitative measurement of the efficiency in which photosensitizers are able to use energy, in the form of light, to convert oxygen in the ground state to the reactive species singlet oxygen, O2(1∆g), useful in photodynamic therapy.

What is singlet and triplet state?

Singlet state: All electrons in the molecule are spin paired. It is called a singlet because there is only one possible orientation in space. Triplet state: One set of electron spins is unpaired. It is called a triplet because there are three possible orientations in space with respect to the axis.

What is Chlorin e6?

Chlorin e6-Coated Superparamagnetic Iron Oxide Nanoparticle (SPION) Nanoclusters as a Theranostic Agent for Dual-Mode Imaging and Photodynamic Therapy.

Is chlorophyll a photosensitizer?

Chlorophyll has been experimented to function as a photosensitizer in dye-sensitized solar cells (DSSCs) as DSSCs mimic the photosynthesis process in green plants. DSSC was first developed by Gratzel in 1991 and since then has gained tremendous attention as its fabrication is cheap and easy.

What is singlet and doublet?

A doublet state occurs when there is an unpaired electron that gives two possible orientations when exposed in a magnetic field and imparts different energy to the system. A singlet or a triplet can form when one electron is excited to a higher energy level.

Why is it called triplet?

A triplet state is an electronic state in which two electrons in different molecular orbitals have parallel spins, as shown in Fig. 4.35. The name “triplet” reflects that there are three triplet sublevels as discussed earlier (see Section 4.15. 1).

What are singlets and triplets?

A singlet state refers to a system in which all the electrons are paired. Whereas, the triplet state of a system describes that the system has two unpaired electrons.

What is the chemical name of singlet oxygen?

Singlet oxygen, systematically named dioxygen(singlet) and dioxidene, is a gaseous inorganic chemical with the formula O=O (also written as 1. [O. 2] or 1. O. 2), which is in a quantum state where all electrons are spin paired.

What is the electron configuration of singlet oxygen?

This state is referred to by the title term, singlet oxygen, commonly abbreviated 1 O 2, to distinguish it from the triplet ground state molecule, 3 O 2. g. These three electronic states differ only in the spin and the occupancy of oxygen’s two antibonding π g -orbitals, which are degenerate (equal in energy).

What is the fluorescence of singlet oxygen?

However, at high singlet oxygen concentrations, the fluorescence of the singlet oxygen “dimol” species—simultaneous emission from two singlet oxygen molecules upon collision—can be observed as a red glow at 634 nm and 703 nm.

What is the fundamental parent of bacteriochlorin?

Bacteriochlorin is a tetrapyrrole fundamental parent that consists of two pyrrole and two reduced pyrrole units connected by methine linkages, where the two reduced pyrroles are located diagonally opposite one another. It is a tetrapyrrole fundamental parent and a member of bacteriochlorins.