Effect of ytterbium amount on LaNbO4:Tm3+,Yb3+ nanoparticles for bio-labelling applications

Autor(es)

Marques, Nathalia da Silva ^[1] ; Nassar, Eduardo Jose ^[1] ; Verelst, Marc ^[2] ; Mauricot, Robert ^[2] ; Brunckova, Helena ^[3] ; Rocha, Lucas Alonso ^[1]

Afiliação do(s) autor(es)

^[1] Univ Franca, Ave Dr Armando de Sales Oliveira, 201 Parque Univ, BR-14404600 Franca, SP - Brazil

^[2] Univ Toulouse, CEMES, CNRS, Toulouse - France

^[3] Slovak Acad Sci, Inst Mat Res, Watsonova - Slovakia

• Tipo de documento: Artigo Científico
• Fonte: ADVANCES IN MEDICAL SCIENCES; v. 65, n. 2, p. 324-331, SEP 2020.
• Citações Web of Science: 0

Resumo

Purpose: This work investigates how Yb3+ concentration affects the luminescent properties of LaNbO4 nanoparticles for medical imaging applications. Due to the highly transparent optical window for organic tissues in the near infrared region (650-1000 nm), upconversion fluorescence allows near infrared wavelengths to penetrate deeply into tissues, which is useful in biomedical areas such as biodetection, activated phototherapy, and screening. Materials/method: Upconversion nanoparticles based on LaNbO4 doped with Tm3+ and Yb3+ were prepared by the one-step industrial process called Spray Pyrolysis. Samples with different Tm3+:Yb3+ molar ratios (1:4, 1:8 and 1:16) were obtained. Results: The X-ray powder diffractograms of all the samples displayed the typical peaks of a crystalline material (tetragonal phase). Emission bands emerged in the blue, red, and near infrared regions, and they corresponded to the Tm3+ (1)G(4) -> H-3(6) (475 nm), (1)G(4) -> F-3(4) (650 nm), F-3(2,3) -> H-3(6) (690 nm), and H-3(4) -> H-3(6) (803 nm) transitions, which indicated a two-photon absorption process. As for bio-labelling application, the results indicated that Yb3+ concentration was directly related to signal intensity. Conclusions: The intensity of positive conversion emissions depends directly on Yb3+ concentration. The biolabelling tests pointed to the potential application of these materials. The sample containing the highest amount of Yb3+ provided better results and was easier to detect than the standard sample. (AU)

• Processo FAPESP: 15/20298-0 - Obtenção de matrizes luminescentes de LaNbO4:Ln (Ln = Dy, TM, er e Yb) pelo processo de pirólise de aerossol
• Beneficiário: Lucas Alonso Rocha
• Modalidade de apoio: Auxílio à Pesquisa - Regular