Eric Bakker

US Patent:

7201876, Apr 10, 2007

Filed:

Mar 7, 2003

Appl. No.:

10/384097

Inventors:

Shane Peper - Los Alamos NM, US
Yu Qin - Auburn AL, US
Eric Bakker - Auburn AL, US

Assignee:

Auburn University - Auburn AL

International Classification:

G01N 27/333
G01N 21/01
G01N 33/20
C07C 69/00
C07C 233/00

US Classification:

422 8203, 204416, 204418, 2057815, 422 56, 422 8201, 422 8202, 422 8205, 422 8206, 422 8207, 422 8208, 422 8209, 422 8211, 436 73, 436 74, 436 79, 436 80, 436 81, 436 82, 436 83, 436 84, 436149, 436150, 436151, 436169, 436172, 560130, 560138, 564123, 564152, 564155, 564192

Abstract:

Ion-detecting sensors for detecting a target ion in a sample are provided. The sensor comprises a plasticizer-free copolymer comprised of polymerized units of methacrylate monomers having pendent alkyl groups of different length and a functionalized ionophore of said ion, wherein at least a portion of the functionalized ionophore is grafted into the copolymer through covalent linkages. Sensors may comprise ionophores such as hydrophilic crown ethers or functionalized derivative of 3-oxapentandiaminde-type ionophores. This invention further provides sensors for detecting target ions in a sample, comprising plasticizer-free molecularly imprinted polymers, wherein the polymers comprise polymerized units of methacrylate monomers having pendent alkyl groups of different length and a functionalized ionophore of said ion. In particular, a magnesium ion sensor comprising a functionalized derivative of a 3-oxapentandiaminde-type calcium ion-selective ionophore is provided. Sensors of this invention include carrier-based ion-selective electrodes or optodes such as thin film ion-specific optodes, particle-based optodes, or bulk optodes.

US Patent:

7208121, Apr 24, 2007

Filed:

Dec 5, 2002

Appl. No.:

10/313090

Inventors:

Shane Peper - Los Alamos NM, US
Yu Qin - Auburn AL, US
Eric Bakker - Auburn AL, US

Assignee:

Auburn University - Auburn AL

International Classification:

G01N 27/333
G01N 21/01
G01N 21/64
G01N 33/20

US Classification:

422 8203, 204416, 204418, 2057815, 422 56, 422 8201, 422 8202, 422 8205, 422 8206, 422 8207, 422 8208, 422 8209, 422 8211, 436 73, 436 74, 436 79, 436 80, 436 81, 436 82, 436 83, 436 84, 436166, 436169, 436172

Abstract:

A plasticizer-free ion detective sensor for detecting a target ion in a sample is provided. The sensor comprises a copolymer of methacrylate monomers with pendant alkyl groups of different length, and an ionophore for detecting the target ion. The copolymer matrix of the present invention may be in a form of membrane or particles. The sensors of the present invention may be Carrier-based ion-selective electrodes (ISEs) or optodes such as thin film ion-specific optodes or particle-based optodes. The ionophore may be a target ionophore selective for a target ion H, Li, Na, K, Ca, or Mg. The ion detective sensor of the present invention may further include an ion exchanger such as halogenated carboranes. Also provided is an ion detective sensor comprising halogenated carboranes as ion exchangers. Particularly, trimethylammonium-2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 undecabromocarborane (TMAUBC) is used as ion exchangers.

US Patent:

7226563, Jun 5, 2007

Filed:

May 28, 2004

Appl. No.:

10/856665

Inventors:

Eric Bakker - Auburn AL, US
Yu Qin - Auburn AL, US

Assignee:

Auburn University - Auburn AL

International Classification:

G01N 27/333
G01N 21/01
G01N 33/20

US Classification:

422 8203, 204416, 204418, 2057815, 422 56, 422 8201, 422 8202, 422 8205, 422 8206, 422 8207, 422 8208, 422 8209, 422 8211, 436 73, 436 74, 436 79, 436 80, 436 81, 436 82, 436 83, 436 84, 436149, 436150, 436151, 436169, 436172

Abstract:

Plasticizer-free ion-detecting sensors for detecting a target ion in a sample are provided. The sensor comprises a plasticizer-free copolymer comprised of polymerized units of methacrylate monomers and a polymerizable ion exchanger, wherein the methacrylated monomers have pendent alkyl groups of different length and wherein the functionalized ion-exchanger is grafted into the copolymer through covalent linkages. The ion exchanger comprises a C-derivative of a halogenated closo-dodecacarborane anion having a polymerizable moiety. Sensors of this invention include carrier-based ion-selective electrodes or optodes such as thin film ion-specific optodes, particle-based optodes, or bulk optodes.

US Patent:

7247489, Jul 24, 2007

Filed:

Mar 7, 2003

Appl. No.:

10/384082

Inventors:

Eric Bakker - Auburn AL, US
Mike Bell - Fullerton CA, US

Assignee:

Auburn University - Auburn AL
Beckman Coulter, Inc. - Fullerton CA

International Classification:

G01N 33/20
G01N 33/52

US Classification:

436 74, 422 8205, 422 8206, 422 8207, 422 8208, 422 8209, 422 8211, 436 73, 436 79, 436 80, 436 81, 436 82, 436 83, 436 84, 436169, 436172, 436523, 436528, 436531, 526318, 5263184, 526319, 526330

Abstract:

This invention provides methods of using ion-detecting microspheres containing an ionphore and a chromoionphore in clinical laboratory instrumentation such as flow cytometry for sample analysis. In one embodiment, the microspheres are contacted with a flowing stream of a sample under conditions that allow the ion-selective ionophores to complex with the ions in the sample, and to cause deprotonation of the chromoionophore. The complexes are then exposed to an excitation wavelength light source suitable for exciting the deprotonated chromoionophore to emit a fluorescence signal pattern. Detection of the fluorescence signal pattern emitted by the deprotonated chromoionophore in microspheres containing the complexes allows for determination of the presence of the target ions in the sample. In one embodiment, lead ion-detecting microspheres are provided that can detect nanomolar levels of lead ions with response times on the order of minutes.

US Patent:

7553403, Jun 30, 2009

Filed:

Jul 8, 2004

Appl. No.:

10/887251

Inventors:

Eric Bakker - Auburn AL, US
Alexey Shvarev - Auburn AL, US

Assignee:

Auburn University - Auburn AL

International Classification:

G01N 27/327
G01N 27/333

US Classification:

2057895, 205789, 205792, 204296, 204418

Abstract:

The present invention is directed to a reversible electrochemical sensor for polyions. The sensor uses active extraction and ion stripping, which are controlled electrochemically. Spontaneous polyion extraction is suppressed by using membranes containing highly lipophilic electrolytes that possess no ion-exchange properties. Reversible extraction of polyions is induced by constant current pulse of fixed duration applied across the membrane. Subsequently, polyions are removed by applying a constant stripping potential. The sensors provide excellent stability and reversibility and allow for measurements of heparin concentration in whole blood samples via protamine titration.

US Patent:

7651858, Jan 26, 2010

Filed:

Jul 17, 2007

Appl. No.:

11/779173

Inventors:

Eric Bakker - Auburn AL, US
Mike Bell - Fullerton CA, US

Assignee:

Auburn University - Auburn AL
Beckman Coulter, Inc. - Fullerton CA

International Classification:

G01N 33/20
G01N 33/52

US Classification:

436 74, 422 8205, 422 8207, 422 8208, 436 73, 436 79, 436 80, 436 81, 436 82, 436 83, 436 84, 436169, 436172, 436523

Abstract:

This invention provides methods of using ion-detecting microspheres containing an ionphore and a chromoionphore in clinical laboratory instrumentation such as flow cytometry for sample analysis. In one embodiment, the microspheres are contacted with a flowing stream of a sample under conditions that allow the ion-selective ionophores to complex with the ions in the sample, and to cause deprotonation of the chromoionophore. The complexes are then exposed to an excitation wavelength light source suitable for exciting the deprotonated chromoionophore to emit a fluorescence signal pattern. Detection of the fluorescence signal pattern emitted by the deprotonated chromoionophore in microspheres containing the complexes allows for determination of the presence of the target ions in the sample. In one embodiment, lead ion-detecting microspheres are provided that can detect nanomolar levels of lead ions with response times on the order of minutes.

US Patent:

7678252, Mar 16, 2010

Filed:

Jun 14, 2006

Appl. No.:

11/424185

Inventors:

Eric Bakker - West Lafayette IN, US
Yu Qin - Beijing, CN

Assignee:

Auburn University - Auburn AL

International Classification:

G01N 27/26

US Classification:

204418, 424450, 600317, 604 20

Abstract:

A graft copolymer having metalloporphyrin ionophores covalently attached in a manner that prevents dimer formation is provided. A method of making the graft copolymer comprises polymerizing a functionalized metalloporphyrin monomer, which includes a polymerizable group, with a co-monomer. Methods for synthesizing the polymerizable metalloporphyrin monomers are provided. The graft copolymer can be incorporated into anion-selective membranes for use in anion-detecting sensors, which have improved longevity and response times.

US Patent:

8097135, Jan 17, 2012

Filed:

Jul 27, 2006

Appl. No.:

11/494885

Inventors:

Eric Bakker - West Lafayette IN, US
Alexey Shvarev - Corvalis OR, US

Assignee:

Auburn University - Auburn AL

International Classification:

G01N 27/327
G01N 27/333

US Classification:

204418, 205789, 205792, 2057895, 204296

Abstract:

The present invention is directed to a reversible electrochemical sensor for polyions. The sensor uses active extraction and ion stripping, which are controlled electrochemically. Spontaneous polyion extraction is suppressed by using membranes containing highly lipophilic electrolytes that possess no ion-exchange properties. Reversible extraction of polyions is induced by constant current pulse of fixed duration applied across the membrane. Subsequently, polyions are removed by applying a constant stripping potential. The sensors provide excellent stability and reversibility and allow for measurements of heparin concentration in whole blood samples via protamine titration. The sensors can also monitor a polyion concentration and an enzyme activity, wherein the polyion decomposition is directly proportional to the enzyme activity in a sample. Additionally, the sensors can monitor an enzyme inhibitor activity. Also, an immunoassay can be used to detect analytes by employing one of a polyion and an enzyme as markers.