Surface Engineering, Bioconjugation, Colloidal Stability and Fluorescent Characteristics of Upconversion Nanoparticles
نویسندگان
1 Department of Chemistry and Biochemistry, School of Sciences, JAIN (Deemed to be University), Bangalore, Karnataka, India
2 Faculty of Engineering, Sohar University, Sohar, Oman
3 Department of Chemistry, Uttaranchal University, Dehradun, India
4 Department of Chemistry, Sathyabama Institute of Science and Technology, Chennai, Tamil Nadu, India
5 Marwadi University Research Center, Department of Mechanical Engineering, Faculty of Engineering & Technology, Marwadi University, Rajkot, Gujarat, India
6 Department of Mechanical Engineering, School of Engineering and Technology, CGC University, Mohali – 140307, Punjab, India
doi
10.22036/ncr.2025.534857.1508چکیده
Upconversion nanoparticles (UCNPs) have attracted considerable attention in biomedical imaging applications. These nanoparticles constitute a novel class of luminescent materials that convert low-energy near-infrared radiation into higher-energy visible light. UCNPs serve as a promising alternative to traditional fluorescent dyes and carbon-based quantum dots, offering advantages such as extremely low background noise, exceptional photostability (resistance to photobleaching), narrow emission spectra, and improved tissue penetration due to low tissue absorption. These features make UCNPs highly suitable for real-time tissue imaging and detection. Upon excitation by near-infrared light, UCNPs emit higher-frequency visible light, resulting in large Stokes shifts that enable low-background fluorescence. The emission color of UCNPs can be precisely tuned by modifying the host material composition and lanthanide ion doping. Various synthesis methods—including Ostwald ripening, thermal decomposition, and hydro(solvo)thermal techniques—are employed to fabricate UCNPs, with nanoparticle morphology controllable during the process. Additional notable benefits of UCNPs include high color purity, ease of surface modification, and excellent colloidal stability. Current research focuses on optimizing preparation methods to enhance their performance and broaden their applications.
