1. Lanthanide Photonics: Shaping the Nanoworld
Jean-Claude G. Bünzli 
Trends in Chemistry 
DOI: /j.trechm
Copyright © 2019 Elsevier Inc. Terms and Conditions

2. Figure 1 Typical Lanthanide Emission Spectra.
(A) EuIII(5D0→7FJ) f-f transitions (J = 0–4) of a triple-stranded helicate with approximate D3 symmetry showing in the right insert the crystal-field splitting of the 7F1 state; adapted from [6]. (B) CeIII(2D3/2→2F7/2,5/2) d-f emission band in Y3Al5O12:CeIII (0.33%) showing the spin-orbit splitting of the 4f1 configuration into 2F7/2 and 2F5/2.
Trends in Chemistry DOI: ( /j.trechm )
Copyright © 2019 Elsevier Inc. Terms and Conditions

3. Figure 2 The Amazing Electronic Structure of Lanthanide Ions.
Calculated energy levels for all 4fn (left, red) and 4fn–15d1 (right, black) electronic configurations of trivalent lanthanide ions. Crystal-field splitting is not considered. Note that for the right scale, 1 eV corresponds to 8066 cm–1. Reproduced with permission from [8].
Trends in Chemistry DOI: ( /j.trechm )
Copyright © 2019 Elsevier Inc. Terms and Conditions

4. Figure 3 Lanthanide Luminescence at Work.
(A) Euro banknote UV-illuminated and displaying the orange-red emission of EuIII (picture from the author’s laboratories). (B) Latent fingerprints on soft media (paper magazine) revealed by illumination at 254 nm of nanoparticles. Reproduced with permission from [18]. (C) QR code printed with NaYF4:Er(10%),Tm(2%) (red), NaYF4:Yb(17%), Er(3%) (green), and NaYF4:Yb(25%),Tm(0.3%) (blue). Reproduced with permission from [19]. (D) Mechanoluminescent sensor SrAl2O4:EuII incorporated into an artificial bone and responding to an increasing mechanical load (0.1–1.9 kNs–1). Reproduced with permission from [20].
Trends in Chemistry DOI: ( /j.trechm )
Copyright © 2019 Elsevier Inc. Terms and Conditions

5. Figure 4 Illuminating Cancerous Cells.
(A) Indirect immunohistochemical assay. (B) Time-resolved detection of two types of BM in a human breast cancer tissue (red: estrogen receptors, EuIII; green: Her2/neu receptors, TbIII). Reproduced with permission from [25]. Abbreviations: BM, Biomarker; LLB, lanthanide luminescent bioprobe; Ln, Lanthanide; P Ab, primary monoclonal antibody; S Ab, secondary monoclonal antibody.
Trends in Chemistry DOI: ( /j.trechm )
Copyright © 2019 Elsevier Inc. Terms and Conditions

6. Figure 5 Sensing Intracellular Temperature.
Top: Optical transmission images of HeLa cells at three different temperatures; cells at 45°C are dead. Bottom: temperature determined by the upconverting nanoparticle thermometer as a function of the voltage applied to the excitation laser (920 nm). Reproduced with permission from [45].
Trends in Chemistry DOI: ( /j.trechm )
Copyright © 2019 Elsevier Inc. Terms and Conditions

7. Figure 6
Upconversion Nanoparticles at Work in Photodynamic Therapy of Cancer.
Working mechanism of a singlet oxygen generation nanoplatform consisting of Reproduced with permission from [48]. Abbreviations: Ce6, Chlorin e6 photosensitizer; cRGD, the cyclic tripeptide Arg-Gly-Asp; EPR, enhanced permeation and retention effect; NIR, near-infrared; PDT, photodynamic; PEG, polyethylene glycol; UCNP, upconverting nanoparticle.
Trends in Chemistry DOI: ( /j.trechm )
Copyright © 2019 Elsevier Inc. Terms and Conditions

8. Figure 7 From Microscopy to Nanoscopy.
(A) Confocal and (B) super-resolution images of 13-nm 8% TmIII-doped upconverting nanoparticles illuminated by 980- and 808-nm lasers. Scale bars: 500 and 200 (insets) nm. (C) Intensity profiles along the dashed lines. Reproduced with permission from [54]. Abbreviations: STED, stimulated emission depletion (microscopy).
Trends in Chemistry DOI: ( /j.trechm )
Copyright © 2019 Elsevier Inc. Terms and Conditions