High performance fluorescence imaging module for genomic testing assay
Fluorescence imaging system designs are described that provide larger fields-of-view, increased spatial resolution, improved modulation transfer and image quality, higher spatial sampling frequency, faster transitions between image capture when repositioning the sample plane to capture a series of images (e.g., of different fields-of-view), and improved imaging system duty cycle, and thus enable higher throughput image acquisition and analysis for genomics and other imaging applications.
1. A method for nucleotide identification comprising:
(a) providing a flow cell comprising (i) a first surface having coupled thereto a first plurality of primed nucleic acid sequences and (ii) a second surface having coupled thereto a second plurality of primed nucleic acid sequences, wherein said second surface is axially-displaced from said first surface;
(b) providing a multiplexed read-head comprising a plurality of microfluorometers, wherein a first microfluorometer of said plurality of microfluorometers is configured to acquire a first wide-field image of a first area of said first surface or said second surface that is different than a second area of said first surface or said second surface in a second wide-field image acquired by a second microfluorometer of said plurality of microfluorometers;
(c) contacting said first plurality of primed nucleic acid sequences coupled to said first surface and said second plurality of primed nucleic acid sequences coupled to said second surface with (1) a plurality of nucleotide moieties comprising a plurality of detectable labels, and (2) a polymerizing enzyme under conditions such that at least a subset of said first plurality of primed nucleic acid sequences and second plurality of primed nucleic acid sequences are subjected to a primer extension reaction; and
(d) imaging said first surface and said second surface using said multiplexed read-head to detect a plurality of signals from at least a subset of said plurality of detectable labels, thereby identifying a nucleotide of a primed nucleic acid sequence of said subset of said first plurality of primed nucleic acid sequences and second plurality of primed nucleic acid sequences.
2. The method of claim 1 , wherein a nucleotide moiety of said plurality of nucleotide moieties is conjugated to a polymer core to form a conjugated polymer-nucleotide.
3. The method of claim 2 , wherein said contacting in (c) comprises contacting said first plurality of primed nucleic acid sequences and said second plurality of said primed nucleic acid sequences with said conjugated polymer-nucleotide to form a transient binding complex between (i) at least one primed nucleic acid sequence of said first plurality of primed nucleic acid sequences or said second plurality of primed nucleic acid sequences and (ii) said nucleotide moiety of said conjugated polymer-nucleotide, wherein said nucleotide moiety is complementary to a nucleotide of said at least one primed nucleic acid sequence.
4. The method of claim 3 , wherein imaging in (d) comprises translating said multiplexed read-head in at least one direction parallel to said first surface or said second surface to detect said transient binding complex.
5. The method of claim 1 , wherein said plurality of nucleotide moieties comprises a nucleotide, a nucleotide analog, or a combination thereof.
6. The method of claim 1 , wherein said plurality of nucleotide moieties comprises a plurality of identical nucleotide moieties.
7. The method of claim 1 , wherein a nucleotide moiety of said plurality of nucleotide moieties further comprises a blocking group coupled thereto.
8. The method of claim 7 , wherein said blocking group comprises O-alkyl hydroxylamine, O-methyl, 3′-phosphorothioate, a 3′-O-malonyl, or a 3′-O-benzyl, or any combination thereof.
9. The method of claim 1 , further comprising repeating (c) and (d) to identify a plurality of nucleotides of said primed nucleic acid sequence.
10. The method of claim 1 , wherein a first subset of microfluorometers of said plurality of microfluorometers images said first surface of said flow cell, and a second subset of microfluorometers of said plurality of microfluorometers images said second surface of said flow cell.
11. The method of claim 1 , wherein said multiplexed read-head aligns with and images individual fluid channels of said flow cell comprising said first surface and said second surface.
12. The method of claim 1 , wherein said plurality of detectable labels comprises a first fluorophore and a second fluorophore, wherein said first fluorophore is different than said second fluorophore.
13. The method of claim 1 , wherein said plurality of detectable labels comprises a first fluorophore and a second fluorophore, wherein said first fluorophore and said second fluorophore are separated by a distance less than λ/2*NA, wherein λ is the center wavelength of a shorter center wavelength of said first fluorophore and second fluorophore, and wherein NA is the numerical aperture of said multiplexed read-head.
14. The method of claim 1 , wherein said plurality of microfluorometers comprises: (1) a first microfluorometer comprising a first sensor configured to detect a first fluorophore; and (2) a second microfluorometer comprising a second sensor configured to detect a second fluorophore, wherein said first fluorophore is different than said second fluorophore.
15. The method of claim 1 , wherein at least one microfluorometer of said plurality of microfluorometers autofocuses on said first surface or said second surface with a dedicated autofocus mechanism.
16. The method of claim 1 , wherein microfluorometers of said plurality of microfluorometers are arranged in an arrangement comprising a hexagonal close pack arrangement, a circular arrangement, or a spiral arrangement.
17. The method of claim 1 , wherein said plurality of signals comprises fluorescent signals.
18. The method of claim 1 , wherein imaging of said second surface comprises moving an optical element into an optical path between said flow cell and said multiplexed read-head.
19. The method of claim 1 , wherein said first wide-field image and said second wide-field image have a resolution of 10 microns or less.
20. The method of claim 1 , wherein said first area comprises said first surface, and said second area comprises said second surface.
21. The method of claim 1 , wherein:
a) said imaging in (d) produces images having a resolution comprising less than or equal to about 10 microns, and comprises moving an optical element into an optical path between said flow cell and said multiplexed read-head;
b) said plurality of microfluorometers further comprises: (1) at least one microfluorometer of said plurality of microfluorometers that autofocuses on said first surface or said second surface with a dedicated autofocus mechanism; and (2) microfluorometers of said plurality of microfluorometers that are arranged in an arrangement comprising a hexagonal close pack arrangement, a circular arrangement, or a spiral arrangement; and
c) said plurality of signals comprise fluorescent signals;
d) said first microfluorometer comprises a first sensor configured to detect a first fluorophore, and a second microfluorometer comprises a second sensor configured to detect a second fluorophore, wherein said first fluorophore and said second fluorophore are separated by a distance less than λ/2*NA, wherein λ is the center wavelength of a shorter center wavelength of said first fluorophore and second fluorophore, and wherein NA is the numerical aperture of said multiplexed read-head.