Quantum dots in pharmacy
Quantum dots (QDs) is a special kind of semiconducting nano materials consisting of a metalic semiconductor core such as CdSe which is most commonly coated by a shell (e.g., ZnS) to improve optical behaviour(11). Their unique properties evolves from their physical size, which ranges from 10-100 A in radius. Due to their some unique features like bright fluorescence, narrow emission, broad UV excitation and high photostability QDs have been utilised in pharmaceutical field of novel research including in-vitro bioimaging for monitoring or tracking of intracellular mechanism of different drugs for longer duration. Quantum-dots have a huge impact on drug development and pharmaceutical research.
Fig 3: Colloidal nanoparticle(Quantum dots) of lead sulfide (selenide)(13)
The following are the some important uses of quanttm dots.(12-13)
1.Quantum-dots is explored as a new divice in the area of diagnosis of diseases including different medical areas like diagnostic tools (MRI),
2. In vitro and in vivo detection of different kind of diseases and analysis of biomolecules can be performed by quantum dots technology.
3. Quantum dots (QDs) have also been investigated as fluorescent labels for immunoassays . QDs are semiconductor nanocrystals whose diameter varies from 2 to 10 nm; their fluorescence emission peak strongly depends on their size as well as their composition. Water-soluble QDs have a surface coating enriched with carboxyl or amine groups, thus facilitating their conjugation with antibodies Immunoassays.
4. DNA hybridization: The density of DNA probes on the QD surface was controlled to avoid steric hindrance and to
promote rapid hybridization with target DNA molecules.
5. development of non-viral vectors for gene therapy, transport vehicles for DNA, protein, drugs or cells, time graded fluorescence imaging of tissue, labeling of cells and as therapeutic tools for cancer treatment (11-13).
11. Resch-Genger, U.; Grabolle, M.; Cavaliere-Jaricot, S.; Nitschke, R.; Nann, T. Quantum dotsversus organic dyes as fluorescent labels. Nat. Methods 2008, 5, 763-775.
12. Schrock, E.; du Manoir, S.; Veldman, T.; Schoell, B.; Wienberg, J.; Ferguson-Smith, M.; Ning,Y.; Ledbetter, D.; Bar-Am, I.; Soenksen, D.; Garini, Y.; Ried, T. Multicolor spectral karyotypingof human chromosomes. Science 1996, 273, 494-497.