Liquid expansion thermometer and microcalorimeter

• US 7,642,096 B2
• Filed: 12/08/2005
• Issued: 01/05/2010
• Est. Priority Date: 12/20/2004
• Status: Expired due to Fees

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Hunter, Ian Warwick, David, Robert
• Primary Examiner(s): Siefke; Samuel P
• Assistant Examiner(s): Handy; Dwayne K
• Application Number:
  US11/297,107
• Publication Number:
  US 20060133951A1
• Time in Patent Office: 1,489 Days
• Field of Search: 422/82.05, 422/82.06, 422/82.09, 436/147, 436/149, 436/150, 436/164, 436/165, 356/43, 356/44, 356/450, 356/451, 356/453, 356/454, 356/477
• US Class Current: 436/147
• CPC Class Codes: G01K 1/065 of liquid column thermometers
• CPC Class Codes: G01K 17/00 Measuring quantity of heat measuring temperature by calorimetry G01K3/00 - G01K11/00; specially adapted for measuring thermal properties of materials, e.g. specific heat, heat of combustion G01N
• CPC Class Codes: G01K 17/006 Microcalorimeters, e.g. using silicon microstructures
• CPC Class Codes: G01K 5/02 the material being a liquid contained in a hollow body having parts which are deformable or displaceable under the pressure developed by the material G01K5/32
• CPC Class Codes: G01N 25/482 concerning the temperature responsive elements measuring temperature or quantity of heat, thermally-sensitive elements G01K; thermoelectric devices H10N10/00, H10N15/00

Abstract

A calorimeter is provided for measuring a quantity of heat. The calorimeter has a liquid constrained so as to allow expansion of the liquid solely in one dimension along a single axis such that liquid expansion may be measured on the basis of light impinging along the single axis of liquid expansion by means of a non-contact displacement transducer. Interferometric optical means for remote measurement of multiple microcalorimeters permits parallel monitoring of multiple chemical reactions and the performance of parallel biochemical assays.

Claims

1. A method for monitoring heat evolved in a chemical reaction, the method comprising:

a. constraining a liquid in a capillary providing a liquid expansion calorimeter, having a liquid therein;

b. conducting heat from the chemical reaction to the liquid expansion calorimeter; and

c. interferometrically measuring the displacement of a surface of the liquid in the capillary and inferring therefrom the heat evolved in the chemical reaction.

2. A method in accordance with claim 1, wherein the chemical reaction is initiated by combining two reactants on the liquid expansion calorimeter.

3. A method in accordance with claim 1, wherein a combination of the two reactants comprises an expansion liquid of the liquid expansion calorimeter.

4. A method for monitoring an array of parallel biochemical assays, the method comprising:

a. constraining a liquid associated with each biochemical assay within a volume including a capillary segment,

b. interferometrically measuring a change in optical pathlength to a surface of the liquid; and

c. correlating the change in optical pathlength to the surface of the liquid with a thermodynamic variable selected from the group of heat, temperature, volume, and pressure.

5. A method in accordance with claim 4, wherein the parallel biochemical assays are conducted within an array of microwells.