Article Highlights
- A newly developed biosensor utilizing Fano resonance metasurface technology enhances disease detection, particularly for pancreatic cancer.
- Fano resonance involves the interaction of discrete and continuum states, creating unique spectral profiles valuable in various fields.
- The biosensor, through coherent coupling of bright and dark modes, exhibits exceptional sensitivity to changes in refractive index units (RUI), reaching up to 842.8 nm/RIU.
- Testing involved detecting the CA242 biomarker for pancreatic cancer, showcasing high accuracy and a low detection limit of 0.0692 ng/mL, offering promise for early cancer diagnosis.
A newly developed biosensor uses Fano resonance metasurface technology can help improve the detection of diseases such as pancreatic cancer, according to a recent study published in Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy (1).
Fano resonance in spectroscopy refers to the phenomenon where an excited discrete state interacts with a continuum of states, leading to a unique asymmetric spectral line shape. This interaction creates interference between the discrete and continuum states, resulting in a characteristic peak and dip in the spectral response. The asymmetric line shape, also known as the "Fano profile," is due to this interference pattern and can be mathematically described by the Fano formula. Fano resonance is valuable in various fields, such as optics, quantum mechanics, and condensed matter physics, and finds applications in enhancing light-matter interactions, controlling energy transfer processes, and designing novel photonic and electronic devices (2).
In this study, the research team, led by Liwei Liu, developed and tested a new type of biosensor that can generate Faro resonance. It accomplishes this goal by using the coherent coupling of bright and dark modes (1). The result is that the sensor can effectively reduce the loss of radiation while enhancing energy concentration and storage within the structure (1). Consequently, the biosensor exhibits an exceptional sensitivity to changes in ambient refractive index units (RUI), boasting an impressive sensitivity of up to 842.8 nm/RIU (1).
This developed biosensor was used in the study to detect CA242 biomarker, which is a key indicator for pancreatic cancer. To accomplish this objective, Liu and the research team made several important antibody functionalization modifications. Testing the biosensor involved mixed and single antigen solutions of varying concentrations, which helped the researchers confirm the biosensor’s sensitivity, specificity, and linear relationship with CA242, with a detection limit as low as 0.0692 ng/mL (1).
The biosensor that was developed has benefits beyond improved specificity and sensitivity. The researchers demonstrated that this biosensor is capable of detecting pancreatic cancer with high accuracy, which is important, because pancreatic cancer is one of the most common cancers affecting patients and one of the deadliest cancers. According to the American Cancer Society, patients afflicted with pancreatic cancer have an average five-year relative survival rate of 13%, when all surveillance, epidemiology, and end result (SEER) stages are averaged together (3).
Unfortunately, there are not many good methods for detecting this type of cancer. Traditional methods for detecting pancreatic cancer have often been marred by lower accuracy and significant patient harm (1). However, this novel biosensor overcomes some of the limitations traditional methods experience by harnessing the wavelength shift of localized surface plasmon resonance in plasma metasurfaces (1).
As a result, this study showcased the potential of metamaterials in biosensing applications reliant on environmental refractive index changes (1). The chiral symmetric double “N” plasmonic metasurface biosensor not only demonstrates sensitivity but also maneuverability (1).
Although this study showcases a new tool to be used for cancer diagnosis, the researchers noted that further enhancements in sensitivity are needed (1). They also discussed how future research studies should examine how to create biosensors capable of detecting multiple tumor biomarkers simultaneously.
Pancreatic cancer is a disease that requires early detection to effectively treat the disease. Because of the development of this biosensor, progress has been made in detecting the presence of pancreatic cancer in the human body, contributing to an advancement in oncology research.
References
(1) Liu, Y.; Ren, S.; Wang, S.; et al. Specific Detection of CA242 by Antibody-Modified Chiral Symmetric Double “N” Metasurface Biosensor. Spectrochimica Acta Part A: Mol. Biomol. Spectrosc. 2024, 309, 123811. DOI: 10.1016/j.saa.2023.123811
(2) Limonov, M.; Rybin, M. V. Poddubny, A. N. Fano Resonances in Photonics. Nat. Photonics 2017, 11, 543–554. DOI: 10.1038/nphoton.2017.142
(3) American Cancer Society, Survival Rates for Pancreatic Cancer. Available at: https://www.cancer.org/cancer/types/pancreatic-cancer/detection-diagnosis-staging/survival-rates.html (accessed 2024-04-25)