Abstract

Polyazamacrocyclic chelates of terbium are shown to be useful in diagnostic medical imaging as tissue site-selective markers. Spectroscopic properties and biodistribution are studied for three terbium(III) species: 3,6,9-tris(methylene phosphonic acid <i>n</i>-butyl ester)- 3,6,9,15-tetraaza-bicyclo[9.3.1]pentadeca-1(15),11,13-triene (abbreviated as PCTMB); 3,6,9-tris(methylene phosphonic acid)-3,6,9,15-tetraazabicyclo[9.3.1]pentadeca-1(13),11,13-triene (abbreviated as PCTMP); and <i>N,N'</i>-bis(methylene phosphonic acid)-2,11-diaza [3.3]-(2,6)pyridinophane (abbreviated as BP2P). The respective aqueous molar absorptivities are found to be 3424, 2513, and 3281/2210 L mole^-1 cm^-1. Fluorescence quantum efficiency is determined against rhodamine 19 in basic ethanol and rhodamine 6G in ethanol. These values are 0.48, 0.21, and 0.40 for Tb-PCTMB, Tb-PCTMP, and Tb-BP2P, respectively. Biodistribution studies performed in Sprague–Dawley rats indicate tissue site-selectivity. Fluorescence images of bone tissues are presented and demonstrate the potential for using the lanthanide chelates to perform site-directed <i>in vivo</i> imaging for the early identification of abnormal tissue.

Bright Terbium Chelate Phosphors

E. L. Fink
Appl. Opt. 7(1) 29-31 (1968)

Confocal light scattering spectroscopic imaging system for in situ tissue characterization

Peter Huang, Martin Hunter, and Irene Georgakoudi
Appl. Opt. 48(13) 2595-2599 (2009)

Cell assay using a two-photon-excited europium chelate

Xudong Xiao, Jeanne P. Haushalter, Kenneth T. Kotz, and Gregory W. Faris
Biomed. Opt. Express 2(8) 2255-2264 (2011)

Deep tissue imaging using spectroscopic analysis of multiply scattered light

Thomas E. Matthews, Manuel Medina, Jason R. Maher, Howard Levinson, William J. Brown, and Adam Wax
Optica 1(2) 105-111 (2014)

Study of yellow luminescence of binary terbium complexes based on 3,3′,4,4′-biphthalic anhydride

Meijuan Lin, Xiaoping Wang, Qiang Tang, Qi An, Huijuan Zeng, and Qidan Ling
Appl. Opt. 53(3) 447-452 (2014)