Systems and methods for fluorescence detection with a movable detection module

• US 8,835,118 B2
• Filed: 07/05/2012
• Issued: 09/16/2014
• Est. Priority Date: 05/08/2003
• Status: Active Grant

• Current Assignee: Bio-Rad Laboratories Incorporated
• Original Assignee: Bio-Rad Laboratories Incorporated
• Inventors: Kordunsky, Igor, Goldman, Jeffrey A., Finney, Michael J.
• Primary Examiner(s): Kim, Young J
• Application Number:
  US13/542,587
• Publication Number:
  US 20130143308A1
• Time in Patent Office: 803 Days
• Field of Search: None
• US Class Current: 435/6.12
• CPC Class Codes: B01L 2300/0654 Lenses; Optical fibres
• CPC Class Codes: B01L 2300/0829 Multi-well plates; Microtitration plates
• CPC Class Codes: B01L 2300/1822 using Peltier elements
• CPC Class Codes: B01L 7/52 with provision for submitting samples to a predetermined sequence of different temperatures, e.g. for treating nucleic acid samples amplification or hybridisation processes per se C12Q1/68; controlling sequential reactions for synthesis B01J19/0046
• CPC Class Codes: C12Q 1/686 Polymerase chain reaction [PCR]
• CPC Class Codes: G01N 21/276 with alternation of sample and standard in optical path
• CPC Class Codes: G01N 21/6452 Individual samples arranged in a regular 2D-array, e.g. multiwell plates
• CPC Class Codes: G01N 2201/0446 Multicell plate, sequential

Abstract

A fluorescence detection apparatus for analyzing samples located in a plurality of wells in a thermal cycler and methods of use are provided. In one embodiment, the apparatus includes a support structure attachable to the thermal cycler and a detection module movably mountable on the support structure. The detection module includes one or more channels, each having an excitation light generator and an emission light detector both disposed within the detection module. When the support structure is attached to the thermal cycler and the detection module is mounted on the support structure, the detection module is movable so as to be positioned in optical communication with different ones of the plurality of wells. The detection module is removable from the support structure to allow easy replacement.

Claims

1. A thermal cycler apparatus comprising:

a housing;

a sample unit within the housing, the sample unit having a plurality of sample wells therein;

an electronic temperature control subsystem operable to regulate a temperature of the sample unit such that the sample wells are held at a succession of specific temperatures for specific lengths of time to complete a reaction cycle;

a heater disposed inside the housing and positioned adjacent to the sample unit, the heater having a plurality of openings therein to permit optical communication with each of the plurality of sample wells; and

a fluorometer assembly disposed inside the housing on a side of the heater opposite the sample wells, the fluorometer assembly including a support structure and a movable subassembly movably mounted on the support structure,

the movable subassembly including a detection module that includes;

a housing having an opening oriented toward the plurality of wells;

a light emitting diode (LED) light source disposed within the housing; and

an emission light detector disposed within the housing,

wherein, during operation of the thermal cycler apparatus, the detection module is movable to be positioned in optical communication with different sample wells of the plurality of sample wells through the plurality of openings in the heater.

2. The thermal cycler apparatus of claim 1 wherein an excitation optical path from the LED light source to the opening has a fixed length and a detection optical path from the opening to the emission light detector has a fixed length.

3. The thermal cycler apparatus of claim 1 further comprising:

a calibration element disposed such that the detection module is movable so as to be positioned in optical communication with the calibration element,

wherein the calibration element provides a known fluorescence response.

4. The thermal cycler apparatus of claim 3 wherein the calibration element is located between two or more of the plurality of wells.

5. The thermal cycler apparatus of claim 3 wherein the calibration element is located in an area peripheral to the plurality of wells.

6. The thermal cycler apparatus of claim 1 further comprising an electronic fluorometry control subsystem operable to move the detection module to interrogate each of the sample wells at a particular time during the reaction cycle.

7. The thermal cycler of claim 6 wherein the electronic fluorometry control system is further operable to coordinate movement of the detection module and operation of the LED light source and the emission light detector such that emission light is measured while the detection module is in motion.

8. The thermal cycler apparatus of claim 1 wherein operation of the LED light source and the emission light detector is controlled by an external computer.

9. The thermal cycler apparatus of claim 1 wherein the reaction cycle is a polymerase chain reaction (PCR) cycle.

10. The thermal cycler apparatus of claim 1 wherein the movable subassembly further includes:

a shuttle movably mounted on the support structure, the movable detection module being mounted on the shuttle.

11. The thermal cycler apparatus of claim 10 wherein the detection module is detachably mounted on the shuttle.

12. The thermal cycler apparatus of claim 10 wherein the fluorometer assembly further includes at least two stepper motors mounted on the support structure, the stepper motors being operable to move the shuttle in at least two dimensions.

13. The thermal cycler apparatus of claim 1 wherein the detection module includes at least two emission light detectors.

14. The thermal cycler apparatus of claim 1 wherein the detection module includes at least two LED light sources.

15. The thermal cycler apparatus of claim 1 wherein the detection module further includes a plurality of optical components defining an excitation optical path for light of an excitation wavelength from the LED light source to the opening of the housing and a detection optical path for light of a detection wavelength from the opening of the housing to the emission light detector.

16. The thermal cycler apparatus of claim 1 wherein the detection module includes a plurality of excitation/detection pairs, each excitation/detection pair being optically isolated from each other excitation/detection pair, and wherein each of the excitation/detection pairs includes:

an LED light source; and

an emission light detector.