Terahertz (THz) waves are characterized by low photon energy, sensitivity to polar molecules, and different spectral responses to many biomolecules, which are of great research and application value in the biomedical field. Metamaterials are very sensitive to changes in the dielectric environment of their surfaces and have great potential in the field of sensing. Aiming at the current needs of terahertz-band biosensors whose sensitivity still needs to be improved, we propose an open-ring resonator biosensor with an asymmetric structure of discontinuous dielectric layers. Simulation results show that the refractive index sensitivity of this discontinuous dielectric layer metamaterial biosensor can reach up to 605 GHz/RIU, it exhibits a figure of merit (FOM) value of 24.2 RIU-1 and a high quality (Q) factor of 79.8, indicating a high Q factor and an ultra-high sensitivity. These characteristics are significant in the design of terahertz ultra-sensitive biosensors, showcasing their valuable application potential.
Gelatin is an irreversible hydrolyzed form of collagen having similar amino acid composites with its parent collagen. The hydrogen atoms on the side chains of the long peptide strings can weakly bond with their surrounding gelatin as well as water molecules in aqueous environment, forming a cross-linked 3D matrix. Gelatin has been used as a model for soft tissue phantoms in several medical imaging studies including in terahertz imaging. In the terahertz regime, the dielectric property of the gelatin relies largely on its hydration status and the relationship has been shown to be non-linear. It is therefore essential to study the change of the dielectric properties with respect to the hydration status so as to accurately mimic the properties of fresh biological tissues in the terahertz spectrum. In this work, we studied the hydration status of gelatin with a terahertz time-domain spectroscopy system in the reflection setup. Gelatin gels with different molar weights were prepared with the weight concentration varying from 0 to 33.3%. The complex dielectric constants of the samples were calculated and fitted with an effective medium approximation model. The results provide a quantitative knowledge on the total number of the water molecules affected by each gelatin molecule and how the hydration status is influenced by the concentration and the molar weight.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.