Compact wide-field fluorescent imaging on a mobile device
Wide-field fluorescent imaging on a mobile device having a camera is accomplished with a compact, light-weight and inexpensive optical components that are mechanically secured to the mobile device in a removable housing. Battery powered light-emitting diodes (LEDs) contained in the housing pump the sample of interest from the side using butt-coupling, where the pump light is guided within the sample holder to uniformly excite the specimen. The fluorescent emission from the sample is then imaged using an additional lens that is positioned adjacent to the existing lens of the mobile device. A color filter is sufficient to create the dark-field background required for fluorescent imaging, without the need for expensive thin-film interference filters.
1. A fluorescent imager comprising:
a mobile phone device having a camera element;
a housing secured to the mobile phone device via gripping elements, the housing having a size less than 100 cm 3 ;
an array of capillary tubes disposed in the housing, the array of capillary tubes containing fluorescently labeled particles;
an excitation light source disposed in the housing and butt-coupled with the array of capillary tubes to illuminate the capillary tubes with a first wavelength in a first direction and wherein the fluorescently labeled particles emit fluorescent light at a second, different wavelength;
a filter holder disposed in the housing and interposed in an optical path formed between the capillary tubes and the camera element and configured to hold filter media therein that receives fluorescent light directed substantially orthogonal to the first direction and permits transmission of the fluorescent light but prevents transmission of excitation light; and
a lens disposed in the housing, wherein the lens is positioned adjacent to the camera element of the mobile phone and within the optical path and receives fluorescent light passing through the filter when the housing is secured thereto, the lens focusing fluorescent light onto the camera element.
2. The fluorescent imager of claim 1 , wherein the gripping elements comprise snap-fit flanges or clips.
3. The fluorescent imager of claim 1 , wherein the filter holder is one of fixed or moveable.
4. The fluorescent imager of claim 1 , further comprising a battery configured to power the excitation light source.
5. The fluorescent imager of claim 1 , wherein the fluorescently labeled particle comprises a pathogen or cell.
6. The fluorescent imager of claim 5 , wherein the fluorescently labeled particle comprises a bacterium.
7. The fluorescent imager of claim 6 , wherein the fluorescently labeled particle comprises E. coli.
8. The fluorescent imager of claim 6 , wherein the capillary tubes are functionalized with anti- E. coli O 157:H7 antibodies.
9. The fluorescent imager of claim 1 , wherein the fluorescently labeled particle comprises an antibody.
10. The fluorescent imager of claim 1 , wherein the housing weighs less than or equal to 30 grams.
11. The fluorescent imager of claim 1 , wherein the fluorescently labeled particle comprises quantum dot based antibody sandwich.
12. The fluorescent imager of claim 1 , further comprising anti-bacteria antibodies covalently attached to an inner surface of the capillary tubes.
13. The fluorescent imager of claim 12 , wherein the anti-bacteria antibodies comprise anti- E. coli antibodies.