UV excitable fluorescent energy transfer dyes

1. An energy transfer dye, comprising:

(a) a donor dye having an absorption maxima at a wavelength between about 300 and about 450 nm; and

(b) an acceptor dye capable of absorbing excitation energy emitted by the donor dye and emitting light in response, the acceptor dye having an emission maxima greater than about 500 nm.

2. The energy transfer dye according to claim 1 , wherein the donor dye has an absorption maxima at a wavelength between about 350 and 400 nm.

3. An energy transfer dye, comprising:

(a) a donor dye having an absorption maxima at a wavelength between about 250 and about 450 nm; and

(b) an acceptor dye capable of absorbing excitation energy emitted by the donor dye and emitting light in response, the acceptor dye having an emission maxima at a wavelength greater than about 550 nm.

4. An energy transfer dye, comprising:

(a) a donor dye having an absorption maxima at a wavelength between about 250 and about 450 nm; and

(b) an acceptor dye capable of absorbing excitation energy emitted by the donor dye and emitting light in response, the acceptor dye having an emission maxima at a wavelength between about 500 and 700 nm.

5. An energy transfer dye, comprising:

(a) a donor dye having an absorption maxima at a wavelength between about 250 and about 450 nm; and

(b) an acceptor dye capable of absorbing excitation energy emitted by the donor dye and emitting light in response, the acceptor dye having an emission maxima at a wavelength at least about 150 nm greater than the absorption maxima of the donor dye.

6. An energy transfer dye, comprising:

(a) a donor dye having an absorption maxima at a wavelength between about 300 and about 450 nm; and

(b) an acceptor dye capable of absorbing excitation energy emitted by the donor dye and emitting light in response, the acceptor dye having an emission maxima greater than about 500 nm,

wherein the acceptor dye is a member of a class of dyes selected from the group consisting of fluorescein, rhodamine, asymmetric benzoxanthene, xanthene, cyanine, phthalocyanine and squaraine dyes.

7. The energy transfer dye according to claim 6 , wherein the acceptor dye is selected from the group consisting of 4,7-dichlorofluorescein dyes, asymmetric benzoxanthene dyes, rhodamine, 4,7-dichlororhodamine dyes, carboxyrhodamines, N,N,N′,N′-tetramethyl carboxyrhodamines, carboxy R110, carboxy R6G, carboxy-X-rhodamines and Cy5.

8. The energy transfer dye according to claim 6 , wherein the acceptor dye is selected from the group consisting of R110, R6G, TAMRA and ROX.

9. An energy transfer dye, comprising:

(a) a donor dye having an absorption maxima at a wavelength between about 300 and about 450 nm; and

(b) an acceptor dye capable of absorbing excitation energy emitted by the donor dye and emitting light in response, the acceptor dye having an emission maxima greater than about 500 nm,

further comprising a linker attaching the donor dye to the acceptor dye.

10. The energy transfer dye according to claim 9 , wherein the linker linking the donor dye to the acceptor dye is such that the acceptor dye absorbs substantially all of the excitation energy emitted by the donor dye, the linker including a functional group selected from the group consisting of an alkene, diene, alkyne, a five-membered ring and a six-membered ring, each of the five-member ring and the six-member ring having at least one unsaturated bond or a fused ring structure.

11. The energy transfer dye according to claim 10 , wherein the linker functional group is a five- or six-membered ring selected from the group consisting of cyclopentene, cyclohexene, cyclopentadiene, cyclohexadiene, furan, thiofuran, pyrrole, isopyrrole, isoazole, pyrazole, isoimidazole, pyran, pyrone, benzene, pyridine, pyridazine, pyrimidine, pyrazine oxazine, indene, benzofuran, thionaphthene, indole and naphthalene.