Core-shell nanofiber-based sensors
Nanofiber-based sensors for the rapid detection, identification, and/or quantification of analytes, including gaseous analytes such as oxygen, are provided. The nanofiber-based sensors can comprise core-shell nanofibers. The core-shell nanofibers can comprise (a) a core comprising a first polymer and an sensor dispersed therein; and (b) a shell disposed coaxially around the core, comprising a second polymer.
1. A core shell nanofiber comprising (a) a core comprising a first polymer and an oxygen sensor dispersed therein; and (b) a shell comprising a second polymer disposed coaxially around the core,
wherein the nanofiber has a diameter of about 1000 nm or less.
2. The nanofiber of claim 1 , wherein the first polymer is oxygen permeable.
3. The nanofiber of claim 2 , wherein the first polymer has an oxygen diffusivity greater than water.
4. The nanofiber of claim 1 , wherein the nanofiber is substantially resistant to photobleaching and heat.
5. The nanofiber of claim 1 , wherein the second polymer is biocompatible.
6. The nanofiber of claim 1 , wherein the first polymer is selected from the group consisting of polyethersulfone and polydimethylsiloxane.
7. The nanofiber of claim 1 , wherein the second polymer is polycaprolactone.
8. The nanofiber of claim 1 , wherein the oxygen sensor comprises a luminophore.
9. The nanofiber of claim 8 , wherein the luminophore exhibits an emission peak of from about 570 nm to about 670 nm.
10. The nanofiber of claim 8 , wherein the oxygen sensor is selected from the group consisting of tris (4,7-diphenyl-1,10-phenanthroliine) ruthenium (II) dichloride, (4,7-diphenyl-1,10-phenanthroliine) ruthenium (II) tetraphenylboron, platinum (II) octaethylporphinedialkylcarbocyanine, and diocadecylcycloxacarbocyanine.
11. The nanofiber of claim 1 , wherein the nanofiber has a diameter of from about 400 nm to about 600 nm.
12. The nanofiber of claim 1 , wherein the the nanofiber has a diameter of from about 401 nm to about 960 nm.
13. The nanofiber of claim 1 , wherein the oxygen sensor and the first polymer are present in the core at weight ratio of the oxygen sensor to the first polymer of from about 1:1000 to about 1:200.
14. A method for measuring oxygen content in a sample, comprising
(a) contacting the sample with a nanofiber of claim 1 ; and
(b) evaluating the optical properties of the oxygen sensor to determine the oxygen content of the sample.
15. The method of claim 14 , wherein the optical property of the oxygen sensor is luminescence.
16. The method of claim 15 , wherein the luminescence is fluorescence.
17. The method of claim 14 , wherein the change in optical property includes a change in intensity of an emission signal.
18. The method of claim 14 , wherein the sample is an aqueous solution.
19. The method of claim 14 , wherein the sample comprises a biological sample.
20. The method of claim 19 , wherein the biological sample comprises cells.
21. The method of claim 14 , wherein the nanofiber monitors the oxygen content level of the sample in real time.
22. The method of claim 14 , wherein the nanofiber exhibits a response time of less than about 10 seconds to a change in oxygen content.
23. The method of claim 22 , wherein the response time is less than about 0.5 seconds.