Devices for real-time polymerase chain reaction
An improved device and system for facilitating polymerase chain reaction including a light source, detector, waveguide, and filters that occupy minimal space and facilitate detection of stationary samples, reduced sample read time, and simultaneous reading of multiple light wavelengths.
1. An instrument for performing polymerase chain reaction with real-time detection comprising:
a sample holder configured to receive one or more sample that each have at least one portion that is generally optically transparent, and that receives a biological sample comprising a nucleic acid to be amplified and at least one fluorescing agent that interacts with the nucleic acid during amplification and that emits light upon excitation by light of a known wavelength;
at least one light emitting diode device that is carried on at least one support substrate and is in electrical communication with a power source, and is adapted to emit light at a plurality of different wavelengths and arranged to emit light in a light pattern;
at least one photodiode array detector adapted to issue signals based upon intensity of light it receives;
a filter wheel including at least one filter pair such that one filter in each pair is an emission filter and one filter in each pair is an excitation filter;
a first excitation doublet lens disposed within the excitation path, the first excitation doublet lens stationary with respect to the filter wheel;
a second excitation doublet lens disposed within the excitation path, the second excitation doublet lens disposed on an opposite side of the filter wheel as the first excitation doublet lens; and
an array of fiber optic bundles, each of the fiber optic bundles having a first end aligned with a light spot of the light pattern of the at least one light emitted diode device and a second end aligned with one of the samples.
2. The instrument of claim 1 , wherein the photodiode array detector reads fluorescence emitted by the fluorescing agent in less than 0.25 seconds.
3. The instrument of claim 1 , wherein the photodiode array detector reads fluorescence emitted by the fluorescing agent in less than 0.1 seconds.
4. The instrument of claim 1 , wherein the photodiode array detector reads fluorescence emitted by the fluorescing agent in less than 0.01 seconds.
5. The instrument of claim 1 , wherein the sample holder is sandwiched between opposing thermoelectric devices.
6. The instrument of claim 1 , wherein each filter allows two or more bands of light wavelengths to pass.
7. The instrument of claim 1 , wherein the instrument simultaneously detects light at multiple wavelengths.
8. The instrument of claim 1 , wherein the filter wheel is configured such that alignment of the excitation filter in an excitation path of light emitted by the at least one light emitting diode device further aligns the emission filter to be within an emission path of light emitted from the at least one fluorescing agent.
9. The instrument of claim 1 , wherein the at least one light emitting diode device comprises a plurality of light emitting diode devices.
10. The instrument of claim 9 , wherein the plurality of light emitting diode devices emit light in a first excitation light pattern, the light passing through the first excitation doublet lens, the excitation filter, and the second excitation doublet lens to produce a second excitation light pattern, the second excitation light pattern being a mirrored to the first excitation light pattern.
11. The instrument of claim 10 , wherein each of the fiber optic bundles has a first end aligned with a light spot of the second excitation light pattern and a second end aligned with one of the samples.
12. The instrument of claim 11 , wherein each fiber optic bundle includes at least one fiber optic cable aligned with each of the samples.
13. The instrument of claim 1 , further comprising first and second emission lenses disposed within an emission path of light emitted from the at least one fluorescing agent, the first and second emission lenses stationary with respect to and disposed on opposite sides of the filter wheel.