Ag₂S nanocrystals as next-generation, heavy-metal free SWIR emitter for biomedical imaging and sensing applications
- There is a growing interest in the exploitation of the short-wave infrared (SWIR), which refers to the wavelength band of light between 900 nm and 2500 nm. Luminophores that emit in the SWIR are used in various areas of telecommunications, photovoltaics, security systems (night vision), and in biomedicine. In particular for biomedical applications, the SWIR range is highly promising because light scattering, absorption, and autofluorescence of tissue and biological compounds are strongly reduced compared to the visible (400–700 nm) and NIR (~700–900 nm). The benefits of SWIR-emissive QDs have been demonstrated for a variety of applications, such as in thermal sensing, as photoelectrochemical biosensor, in in vivo vascular imaging, and for fluorescence-guided surgery.
Full exploitation of SWIR photoluminescence (PL) imaging and sensing is currently hampered by i.) a lack of suitable advanced nanomaterials with a high PL quantum yield (PL QY) and a high brightness, that can be usedThere is a growing interest in the exploitation of the short-wave infrared (SWIR), which refers to the wavelength band of light between 900 nm and 2500 nm. Luminophores that emit in the SWIR are used in various areas of telecommunications, photovoltaics, security systems (night vision), and in biomedicine. In particular for biomedical applications, the SWIR range is highly promising because light scattering, absorption, and autofluorescence of tissue and biological compounds are strongly reduced compared to the visible (400–700 nm) and NIR (~700–900 nm). The benefits of SWIR-emissive QDs have been demonstrated for a variety of applications, such as in thermal sensing, as photoelectrochemical biosensor, in in vivo vascular imaging, and for fluorescence-guided surgery.
Full exploitation of SWIR photoluminescence (PL) imaging and sensing is currently hampered by i.) a lack of suitable advanced nanomaterials with a high PL quantum yield (PL QY) and a high brightness, that can be used safely in vivo and ii.) a lack of quantitative and reliable data on the optical properties of many SWIR emitters. Promising nanomaterials for the SWIR are heavy metal-free Ag2S quantum dots (QDs).
Aiming for the development of SWIR advanced nanomaterials with optimum performance, we have dived deeper into the photophysical processes occurring in these nanomaterials, thereby exploring in depth how the environment such as temperature, surface ligand composition, and the incorporation of transition metals influence the optical properties Ag2S QDs. We observed a strong enhancement of the SWIR emission of upon addition of metal ions such as Zn2+, yielding PL quantum yields of about 10% and thus making them highly suitable for non-invasive deep imaging of vascular networks and 3D fluid flow mapping.…


| Autor*innen: | Karl David WegnerORCiD |
|---|---|
| Koautor*innen: | B. H. Juarez, Ute Resch-GengerORCiD |
| Dokumenttyp: | Vortrag |
| Veröffentlichungsform: | Präsentation |
| Sprache: | Englisch |
| Jahr der Erstveröffentlichung: | 2025 |
| Organisationseinheit der BAM: | 1 Analytische Chemie; Referenzmaterialien |
| 1 Analytische Chemie; Referenzmaterialien / 1.2 Biophotonik | |
| DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
| Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurwissenschaften und zugeordnete Tätigkeiten | |
| Freie Schlagwörter: | Photoluminescence; Quantum dots; Quantum yield; SWIR; Short-wave infrared; Spectroscopy |
| Themenfelder/Aktivitätsfelder der BAM: | Chemie und Prozesstechnik |
| Chemie und Prozesstechnik / Chemische Charakterisierung und Spurenanalytik | |
| Material | |
| Material / Advanced Materials | |
| Veranstaltung: | Shining a light on biomedical and energy applications (Shift) |
| Veranstaltungsort: | Tenerife, Spain |
| Beginndatum der Veranstaltung: | 13.10.2025 |
| Enddatum der Veranstaltung: | 17.10.2025 |
| Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
| Datum der Freischaltung: | 12.11.2025 |
| Referierte Publikation: | Nein |
| Eingeladener Vortrag (wissenschaftliche Konferenzen): | Nein |

