Ytterbium 10-carboxyperylene-3,4,9-tricarboxylates for targeted NIR luminescent bioimaging.

Two new ytterbium coordination compounds Yb(HPTC)(H2O)2 (Yb1) and Yb(HPTC)(Phen) (Yb2) were obtained using 10-carboxyperylene-3,4,9-tricarboxylate ion (HPTC3-) as a sensitizer. Both coordination compounds exhibited intense NIR-II luminescence upon excitation in the visible range and formed stable suspensions with nanoparticles of 50-70 nm in size in an aqueous solution of sodium alginate. Both complexes demonstrated non-toxicity up to at least 25 mg L-1 in two cell cultures: cancer cells MCF7 and embryonic cells HEK293T - making them suitable for bioimaging. For both complexes, the accumulation in cells was directly measured and it was shown that the accumulation of Yb2 was the same for both cell types (0.51-0.52 πg per cell), while Yb1 demonstrated selective accumulation in cancer cells (0.04 πg per cell for HEK293T and 7.00 πg per cell for MCF7). Thus, Yb1 can also be proposed as a selective vis-excited NIR emitting bioprobe.

NIR luminescence thermometers based on Yb-Nd coordination compounds for the 83-393 K temperature range.

Multimetallic neodymium-ytterbium-gadolinium compounds with 9-anthracenate and 9-acridinate anions were tested in order to create the first luminescent thermometer for elevated temperatures. High luminescence intensity and high signal resolution were reached thanks to the concentration quenching elimination due to the partial substitution of the emitting ions with Gd3+. As a result, NIR emitting materials for luminescence thermometry in the wide temperature range (83-393 K) based on lanthanide coordination compounds (CCs) were obtained. The best thermometric properties among the studied systems were demonstrated by Yb0.02Nd0.12Gd0.86(ant)3, and its temperature sensitivity reached 1.8% K-1 in the temperature range of 293-393 K.