Degradable taggant and method of making and using thereof
The present invention is a low-cost, easily deployed, degradable taggant that can be dispersed over a wide area to serve as a witness to activity in the area and for queuing of other sensors. The taggant enables nearly real-time change detection within the treated area using one or more simple optical sensing techniques.
1. A method of identifying changes comprising:
dispersing a taggant;
detecting a taggant signal;
recording a first signal;
detecting a second signal;
recording said second signal;
comparing said first signal to said second signal; and
identifying differences between said first signal and said second signal;
wherein said taggant signal fades or degrades over time.
2. The method of claim 1 , wherein said taggant is a composition comprising one or more fluorophores and a substrate.
3. The method of claim 1 , wherein said taggant is not detectable by the unaided eye.
4. The method of claim 1 , wherein said taggant further comprises an odorant.
5. The method of claim 1 , wherein said taggant comprises one or more fluorophores and a substrate.
6. The method of claim 5 , wherein said one or more fluorophores is a laser dye.
7. The method of claim 6 , wherein said one or more dye is selected from the group consisting of tetraphenylporphyrin, indodicarbocyanine, indotricarbocyanine, HITCI, HITCP, and Rhodamine 6G.
8. The method of claim 5 , wherein said substrate is metal nanoparticles, a semiconductor or an insulator.
9. The method of claim 8 , wherein said semiconductor is titanium dioxide.
10. The method of claim 9 , wherein said insulator is selected from the group consisting of gold, silica, PVA and hydroxyceilulose.
11. The method of claim 5 , wherein said substrate further comprises an alkane.
12. The method of claim 1 , wherein said taggant further comprises an antioxidant or redox active material.
13. The method of claim 12 , wherein said antioxidant is butylated hydroxytoluene.
14. The method of claim 1 , Wherein said dispersing is by spreading, spraying, or dusting.
15. A composition comprising one or more fluorophores and a substrate, wherein said substrate comprises alkane derivatized titanium dioxide particles or alkane derivatized silicon dioxide particles.
16. The composition of claim 15 , wherein said one or more fluorophores is a laser dye.
17. The composition of claim 16 , wherein said one or more dye is selected from the group consisting of tetraphenylporphyrin, indodicarbocyanine, indotricarbocyanine, HITCI, HITCP, and Rhodamine 6G.
18. The composition of claim 15 , further comprising an antioxidant or a redox active material.
19. The composition of claim 18 , wherein said antioxidant is butylated hydroxytoluene.
20. A method of identifying changes comprising:
dispersing a taggant;
detecting a taggant signal;
recording a first signal;
detecting a second signal;
recording said second signal;
comparing said first signal to said second signal; and
identifying differences between said first signal and said second signal;
wherein said taggant further comprises an odorant.