Optical nanosensor design with uniform pore geometry and large particle morphology

Sherif A. El-Safty*, Adel A. Ismail, Hideyuki Matsunaga, Fujio Mizukami

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

73 Citations (Scopus)


Appropriate design of nanosensors for optically selective, sensitive sensing systems is needed for nakedeye detection of pollutants for environmental cleanup of toxic heavy-metal ions. Mesostructured materials with two- or three-dimensional (2D or 3D) geometries and large particle morphologies show promise as probe carriers, and can therefore be used to reproducibly fabricate uniformly packed nanosensors. This is the first report on the effects of significant key properties of the mesostructured carriers, such as morphology, geometry, and pore shape, on the functionality of optical nanosensor designs. Such mesostructured sensors with superior physical characteristics can be used as components in sensing systems with excellent stability and sensitivity, and with rapid detection response. The nanosensor design can enhance the selectivity even at low concentrations of the pollutant target ions (nanomolar level). Among the nanosensors developed here, the large poresurface grains of highly ordered 3D monoliths (HOM) exhibited a high adsorption capability of the Pyrogallol Red probe and high accessibility to analyte ion transport, leading to possible naked-eye detection of SbIII ions at concentrations as low as 10-9 mol dm-3 and at a wide detection range of 0.5 ppb to 3 ppm. A key finding in our study was that our mesostructured nanosensor designs retained highly efficient sensitivity without a significant increase in kinetic hindrance, despite the slight decrease of the specific activity of the electron acceptor/donor strength of the probe functional group after several regeneration/reuse cycles. The results, in general, indicate that large-scale reversibility of optical nanosensors is feasible in such metal-ion sensing systems.

Original languageEnglish
Pages (from-to)9245-9255
Number of pages11
JournalChemistry - A European Journal
Issue number33
Publication statusPublished - 2007
Externally publishedYes


  • Antimony
  • Mesoporous materials
  • Nanostructures
  • Sensors
  • Toxic ions

ASJC Scopus subject areas

  • Chemistry(all)


Dive into the research topics of 'Optical nanosensor design with uniform pore geometry and large particle morphology'. Together they form a unique fingerprint.

Cite this