Bioanalytics using plasmonic nanoparticles

 

Wolfgang Fritzsche, Leibniz-Institute of Photonic Technology, Germany

(wolfgang.fritzsche@ipht-jena.de)

 

Host: Pedro Viana Baptista, UCIBIO NOVA

 

ZOOM link: https://ucibio.pt/l/GuestSeminars

ID da reunião: 865 7786 0516

Senha: 805165

 

Abstract

 

Today, innovative tools for diagnostics and bioanalytics are needed, to be usable outside of dedicated laboratories and with less qualified personnel, at minimal costs.  

 

Plasmonic nanostructures promise to provide sensing capabilities with the potential for ultrasensitive and robust assays in a high parallelization and miniaturization, and without the need for markers. Upon binding of molecules, the localized surface plasmon resonance (LSPR) of these structures is changed, and can be used as sensoric readout [1]. This is possible even on a single nanostructure level, using optical darkfield detection introduced more than 100 years ago [2], as demonstrated for DNA detection [3]. In contrast to SPR, LSPR senses only in a very thin layer (on the scale of the particle diameter), resulting in an efficient background suppression [4].

 

In order to multiplex this approach, an imaging spectrometer based on a Michelson interferometer has been developed, able to readout a whole array of sensors in one step [5]. On the sensor side, microarrays of gold nanoparticle spots were fabricated using spotting of pre-synthesized gold nanoparticles [6]. Such chemically synthesized particles allow for a cost-efficient generation of highly crystalline particles as nanosensors; by using microfluidic approaches, a higher quality and reproducibility can be achieved [7]. Using this microarray approach, a multiplex DNA-based detection of fungal pathogens involved in sepsis could be demonstrated [8]. DNA-based signal amplification, such as hybridization chain reaction, improves the sensitivity [9]. Beyond DNA detection, LSPR sensing is also applicable for the detection of protein targets, such as CRP [10].

 

References

1. Philosophical Transactions A 369, 3483 (2011).
2. Angew Chem Int Ed 51, 11208 (2012)
3. J Nanopart Res 15, 1531 (2013)              
4. Sensing and BioSensing Research 7, 62 (2016)
5. Biosensors and Bioelectronics 81, 287 (2016)
6. Analytical and Bioanalytical Chemistry 411, 1537 (2019)
7. Chemical Engineering Journal 288 432 (2016)
8. ACS Sensors 4, 335 (2019)
9. Biosensors and Bioelectronics 167, 112465 (2020)
10. Scientific Reports 12, 836 (2022)

 

 

Biosketch 

 

Wolfgang Fritzsche is head of the Department Nanobiophotonics at the Leibniz-Institute of Photonic Technology (Leibniz-IPHT). Leads the Nanobiophotonics group, which develops innovative methods for molecular detection based on the optical properties of plasmonic nanoparticles in combination with molecular components. This so-called Molecular Plasmonics includes passive approaches, such as the development of optical markers, and is focused on application of plasmon nanostructures for bioanalytics. On the other hand, in active plasmonics, plasmonic effects are used to manipulate biomolecules or for catalysis. Wolfgang Fritzsche is involved in teaching Physical Chemistry as well as Instrumental Analytics for pharmacists, Optical Sensors/Microfluidics in the master‘s degree programme Medical Photonics, and Nanobiophotonics in the master‘s degree programme Chemistry of Materials.