Analysis of arrays by laser induced breakdown spectroscopy

• US 20090290151A1
• Filed: 02/26/2009
• Published: 11/26/2009
• Est. Priority Date: 03/03/2008
• Status: Active Grant

• Current Assignee: Ajjer, LLC
• Original Assignee: Ajjer, LLC
• Inventors: Agrawal, Anoop, Tonazzi, Juan Carlos L.
• Granted Patent: US 8,687,189 B2
• Time in Patent Office: Days
• US Class Current: 356/318
• CPC Class Codes: G01N 2021/0346 Capillary cells; Microcells
• CPC Class Codes: G01N 2021/0357 Sets of cuvettes
• CPC Class Codes: G01N 21/03 Cuvette constructions
• CPC Class Codes: G01N 21/6452 Individual samples arranged in a regular 2D-array, e.g. multiwell plates
• CPC Class Codes: G01N 21/718 Laser microanalysis, i.e. with formation of sample plasma

Abstract

The present invention relates to the detection of materials using laser induced breakdown spectroscopy (LIBS). This invention discloses methods to draw the analyte of interest in a homogeneous matrix and subsequent analysis of these matrices, wherein the said matrices are preferably arranged in an array format. This invention is particularly applicable to analysis of Liquid samples arranged in an array format.

Claims

1. A method of determining the presence or amount of an analyte in a sample that is extracted in a homogeneous matrix, and then forming an array of several array-elements wherein each of such array-elements is formed by samples extracted into homogenous matrices, and then subjecting the said array for compositional analysis by LIBS.

2. A method of determining the presence or amount of an analyte as in claim 1 wherein the said array includes array-elements comprising of the analyte, calibration standards and references.

3. A method of determining the presence or amount of an analyte as in claim 1, where the said analyte comprises at least one of lead, mercury, cadmium, arsenic, beryllium, thallium, antimony, uranium and selenium.

4. A method of determining the presence or amount of an analyte as in claim 1 where the matrix is a solid or a liquid.

5. The method in claim 1 wherein the array is located on a plate with 24, 96, 384 or 1536 elements.

6. A method of determining the presence or amount of an analyte by LIBS in several samples, wherein

a. the samples are located on an array as separate array-elements;

b. the samples are in a homogenous liquid matrix;

c. the array-elements are sealed with a lid wherein the sealed array element is permeable to the excitation laser and the said laser ablates a part of the liquid from within the said array element,

d. and the sealed array element is permeable to at least one of the resulting “

ablation products” and

the “

emission spectra”

.

7. A method of determining the presence or amount of an analyte by LIBS in several samples, wherein

a. the samples are located on an array plate as separate array-elements;

b. the samples are in a homogenous liquid matrix;

c. A robotic arm is used to insert the array plate in and out of the LIBS analyzer automatically.

8. A method of determining the presence or amount of an analyte as in claim 7, wherein the said robotic arm is integrated with a liquid handling system which is used in preparation of the array plate.

9. A method of determining the presence or amount of an analyte by LIBS in several liquid samples, wherein the samples are located on an array plate as separate array-elements, and the liquids are constrained in each array element by using one or more of an additive or a medium or a method that is

a. Porous

b. Swells in presence of the said liquid

c. Changes viscosity or forms a gel

d. Solidifies the liquid

e. Restrained as a thin film

10. A method of determining the presence or amount of binding of a protein to a chemical by LIBS, wherein several samples are arranged in an array format.

11. A plate for analysis comprising an array of wells, wherein the sample is prepared by concentrating the solution in the wells, and the walls of the well are nonwetting towards the liquid in the well and the bottom of the well is either wetting towards the liquid in the well or textured.

12. A plate for analysis comprising an array of wells as in claim 11 wherein the analysis is done by LIBS or fluorescence.

14. A plate for analysis as in claim 12 wherein fluorescence includes optical fluorescence and X-ray fluorescence.

13. A plate for analysis comprising an array of wells, wherein the bottom of the plate can be separated from the walls of the said plate, and the residual material array on the said plate is analyzed.