| 1. |
- Di Natale, Corrado, et al.
(författare)
-
Investigation of quartz microbalance and ChemFET transduction of molecular recognition events in a metalloporphyrin film
- 2009
-
Ingår i: Sensors and actuators. B, Chemical. - : Elsevier BV. - 0925-4005. ; 135:2, s. 560-567
-
Tidskriftsartikel (refereegranskat)abstract
- Progresses of synthetic chemistry methodologies have allowed the preparation of a great variety of artificial receptors that are particularly appealing for chemical sensor development. In this paper, we investigate and compare the properties of gas sensors based on two types of devices, quartz microbalances (QMBs) and field effect transistors (FETs), which give the means to exploit the molecular recognition events occurring in non-conductive sensing layers formed by a thiol-modified cobalt tetraphenylporphyrin (CoTPPSH). Since QMB is sensitive to mass and FET is sensitive to electric dipoles, the resulting sensors are expected to exhibit different sensitivities and selectivities, although both based on the same sensing layer. In particular we show that the high sensitivity of CoTPPSH-coated FETs towards CO and NO is a consequence of the significant CoTPPSH electric dipole change after the gas coordination to the metal centre.
|
|
| 2. |
- Dini, Francesca, et al.
(författare)
-
Chemical sensitivity of self-assembled porphyrin nano-aggregates
- 2009
-
Ingår i: NANOTECHNOLOGY. - : IOP Publishing. - 0957-4484 .- 1361-6528. ; 20:5, s. 055502-
-
Tidskriftsartikel (refereegranskat)abstract
- Nanostructured molecular assemblies may provide additional sensing properties not found in other arrangements of the same basic constituents. Among three-dimensional structures, nanotubes are particularly appealing for applications as chemical sensors, because of the potential inclusion of different guests inside the cavity or the induced modification of the skeletal interaction after analyte binding. Porphyrins are a class of compounds characterized by brilliant sensing properties, appearing also in non-ordered solid-state aggregates. In recent years, it was reported that aggregation of oppositely charged porphyrins led to the formation of self-assembled nanotubes and in this paper their sensing properties, both in solution and in the solid state, have been investigated. The interactions of porphyrin nanotubes with guest molecules have been monitored by following the changes in their UV-vis spectra. The results obtained have been exploited to build up a sensing platform based on a computer screen as a light source and a digital camera as detector. Porphyrin nanostructures exhibited an enhanced sensitivity to different compounds with respect to those shown by single porphyrin subunits. The reason for the increased sensitivity may be likely found in an additional sensing mechanism related to the modulation of the strength of the forces that keep the supramolecular ensemble together.
|
|
| 3. |
- Dini, Francesca, et al.
(författare)
-
Combining porphyrins and pH indicators for analyte detection
- 2015
-
Ingår i: Analytical and Bioanalytical Chemistry. - : Springer. - 1618-2642 .- 1618-2650. ; 407:14, s. 3975-3984
-
Tidskriftsartikel (refereegranskat)abstract
- High sensitivity and cross-selectivity are mandatory properties for sensor arrays. Although metalloporphyrins and pH indicators are among the most common and appropriate choices for the preparation of optical sensor arrays, the sensitivity spectrum of these dyes is limited to those analytes able to induce an optical response. To extend the receptive field of optical sensors, we explore the design of composite materials, where the molecular interaction among the subunits enriches their sensing working mechanisms. We demonstrate that blends of single metalloporphyrins and pH indicators, tested with a transduction apparatus based on ubiquitous and easily available hardware, can be endowed with sensing properties wider than those of single constituents, enabling the recognition of a broad range of volatiles.
|
|
