Motivated by the SERS sensitivity to very small amounts of material we are interested in the application of the SERS technique for studying complex biological systems, such as cells. Surface Enhanced Raman Spectroscopy (SERS) is a very sensitive technique that employs rough substrates with structures in the nanometer range to enhance the Raman signal produced by adsorbed species. In SERS the effective Raman cross-section can be increased by many orders of magnitude. Using nanometer-size Ag particles deposited on GaAs surfaces as SERS-active substrates we have obtained an enhancement of Raman signal of human spermatozoa. In the presence of SERS-active substrate we have not observed any other significant spectral differences, indicating that there are not interaction of the cells with the surface. This is an important and crucial point concerning SERS studies of biological systems. It means that our SERS-active substrates serve only as amplifiers of Raman scattering and that the molecular structure of the cells is preserved after deposition on our SERS-active platform. In our opinion this kind of SERS-active substrates with nanometer-sized Ag particles on semiconductors might have promising application in nanoscale science and technology. In fact bio-molecules, cells and processes of their interfacing with Si, GaAs, silver and gold and other inorganic substrates, form the basis of bioelectronics a new emerging field at the crossing of molecular biology and nano-electronics with numerous electronic and biotechnological applications.
Human spermatozoa on nanostructured Ag deposited on GaAs surface
Quagliano L G
2003
Abstract
Motivated by the SERS sensitivity to very small amounts of material we are interested in the application of the SERS technique for studying complex biological systems, such as cells. Surface Enhanced Raman Spectroscopy (SERS) is a very sensitive technique that employs rough substrates with structures in the nanometer range to enhance the Raman signal produced by adsorbed species. In SERS the effective Raman cross-section can be increased by many orders of magnitude. Using nanometer-size Ag particles deposited on GaAs surfaces as SERS-active substrates we have obtained an enhancement of Raman signal of human spermatozoa. In the presence of SERS-active substrate we have not observed any other significant spectral differences, indicating that there are not interaction of the cells with the surface. This is an important and crucial point concerning SERS studies of biological systems. It means that our SERS-active substrates serve only as amplifiers of Raman scattering and that the molecular structure of the cells is preserved after deposition on our SERS-active platform. In our opinion this kind of SERS-active substrates with nanometer-sized Ag particles on semiconductors might have promising application in nanoscale science and technology. In fact bio-molecules, cells and processes of their interfacing with Si, GaAs, silver and gold and other inorganic substrates, form the basis of bioelectronics a new emerging field at the crossing of molecular biology and nano-electronics with numerous electronic and biotechnological applications.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.