Terbium macrocyclic complexes

We plan to take advantage of ligand-induced enhancement of dipicolinate binding affinity to improve current bacterial spore detection technologies in two ways. The first involves appending terbium(macrocycle) complexes to solid polymer substrates to improve microscopy-based endospore assays. In a second method, we will bind lanthanide complexes to silica to concentrate dipicolinate from very dilute samples on colmnns. 

Examples of this include some Tb and Eu macrocyclic complexes, immobilised in a sol-gel glass, whose emission is made pH-dependent and can thus be used as narrow range pH sensors, and a terbium complex which behaves as a molecular logic gate the output (a terbium emission hue) is only observed when the inputs (the presence of proteins and the absence of oxygen) are both satisfied. (Figure 22). 

Montgomery, C.P., Parker, D., and Lamarque, L. (2007) Effective and efficient sensitisation of terbium luminescence at 355 nm with cell permeable pyrazoyl-l-azaxanthone macrocyclic complexes. Chemical Communications, 3841-3843. 

The luminescence of terbium (42) and europium macrocyclic complexes have been studied and found to depend upon pH. The phenanthridine sidechain acts as a photosensitizer and (42) exhibits luminescence quenched by molecular oxygen corresponding Eu compounds exhibit halide-quenched emisssion. ... 

Parker D. Williams J.A.C. Taking advantage of the pH and pO(2) sensitivity of a luminescent macrocyclic terbium phenanthridyl complex. Chem. Cornmun. 1998. 245-246. 

Parker, D., Senanayake, P. K., Williams, J. A. G., Luminescent sensors for pH, p0(2), halide and hydroxide ions using phenanthridine as a photosensitiser in macrocyclic europium and terbium complexes. J. Chem. Soc., Perkin Trans. 21998, 2129-2139. 

When Nd or Yb complexes of a similar macrocycle are covalently linked to a palladium porphyrin complex, this sensitizes near-IR emission from the lanthanide, enhanced in the absence of oxygen and in the presence of a nucleic acid7 Another application of luminescence accompanies the terbium complex shown in (39) whose luminescence is enhanced by binding to zinc, and can therefore signal for that metal. " ... 

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