| Molecular recognition at surfaces derivatized with self-assembled monolayers -> Monitor Keywords |
|
|
  Molecular recognition at surfaces derivatized with self-assembled monolayersUSPTO Application #: 20060040276Title: Molecular recognition at surfaces derivatized with self-assembled monolayers Abstract: An article suitable for use as a biosensor includes a molecule of a formula X—R-Ch adhered to a surface of the article as part of a self-assembled monolayer. X is a functionality that adheres to the surface, R is a spacer moiety, and Ch is a chelating agent. A metal ion can be coordinated by the chelating agent, and a polyamino acid-tagged biological binding partner of a target biological molecule coordinated to the metal ion. A method of the invention involves bringing the article into contact with a medium containing or suspected of containing the target biological molecule and allowing the biological molecule to biologically bind to the binding partner. The article is useful particularly as a surface plasmon resonance chip. (end of abstract) Agent: Foley Hoag, LLP Patent Group, World Trade Center West - Boston, MA, US Inventors: Cynthia C. Bamdad, George B. Sigal, Jack L. Strominger, George M. Whitesides USPTO Applicaton #: 20060040276 - Class: 435006000 (USPTO) Related Patent Categories: Chemistry: Molecular Biology And Microbiology, Measuring Or Testing Process Involving Enzymes Or Micro-organisms; Composition Or Test Strip Therefore; Processes Of Forming Such Composition Or Test Strip, Involving Nucleic Acid The Patent Description & Claims data below is from USPTO Patent Application 20060040276. Brief Patent Description - Full Patent Description - Patent Application Claims
RELATED APPLICATIONS [0001] This application is a continuation-in-part, and a divisional, of U.S. patent application Ser. No. 08/312,388, filed Sep. 26, 1994 by Bamdad, et al., now pending. FIELD OF THE INVENTION [0002] The present invention relates generally to the derivatization of surfaces for determination of analytes, for example from a fluid medium using a biological binding partner of the analyte. More particularly, the invention relates to the formation on a metal surface of a self-assembled molecular monolayer that exposes a binding partner to an analyte medium in a manner such that analysis of high sensitivity obtains. BACKGROUND OF THE INVENTION [0003] Biochemical analyses are invaluable, routine tools in health-related fields such as immunology, pharmacology, gene therapy, and the like. In order to successfully implement therapeutic control of biological processes, it is imperative that an understanding of biological binding between various species is gained. Indeed, an understanding of biological binding between various species is important for many varied fields of science. [0004] Many biochemical analytical methods involve immobilization of a biological binding partner of a biological molecule on a surface, exposure of the surface to a medium suspected of containing the molecule, and determination of the existence or extent of molecule coupling to the surface-immobilized binding partner. [0005] One such technique recently introduced is surface plasmon resonance. This technique utilizes a glass slide having a first side on which is a thin metal film and a second side opposite the first side (known in the art as a sensor chip), a prism, a source of monochromatic and polarized light, a photodetector array, and an analyte channel that directs a medium suspected of containing an analyte to the exposed surface of the metal film. A face of the prism is separated from the second side of the glass slide (the side opposite the metal film) by a thin film of refractive index matching fluid. Light from the light source is directed through the prism, the film of refractive index matching fluid, and the glass slide so as to strike the metal film at an angle at which total internal reflection of the light results, and an evanescent field is therefore caused to extend from the prism into the metal film. This evanescent field can couple to an electromagnetic surface wave (a surface plasmon) at the metal film, causing surface plasmon resonance. [0006] Coupling is achieved at a specific angle of incidence of the light with respect to the metal film (the SPR angle), at which the reflected light intensity goes through a minimum due to the resonance. This angle is determined by a photodetector array as the angle of reflectance and is highly sensitive to changes in the refractive index of a thin layer adjacent to the metal surface. Thus it is highly sensitive to coupling of an analyte to the surface of the metal film. For example, when a protein layer is adsorbed onto the metal surface from an analyte-containing medium delivered to the surface by the analyte channel, the SPR angle shifts to larger values, and this shift is measured by the photodetector array. An article by Stenberg, Persson, Roos, and Urbaniczky, entitled "Quantitative Determination of Surface Concentration of Protein with Surface Plasmon Resonance Using Radiolabeled Proteins", Journal of Colloid and Interface Science, 43: 2, 513-526 (1991), and references therein, describe the technique of surface plasmon resonance. Instrumentation for analysis via surface plasmon resonance is available from Pharmacia Biosensor, Piscataway, N.J., under the trademark BIAcore.TM.. [0007] Although the introduction of SPR represents an extremely valuable contribution to the scientific community, current state-of-the-art SPR instrumentation lacks the sensitivity needed to detect and analyze certain biological interactions that are at the forefront of scientific inquiry. Experimentation conducted in connection with the instant invention has led to identification of several complications associated with prior art sensor chips, which complications hinder the sensitivity of current SPR techniques. According to one technique for immobilization of a binding partner of an analyte on a surface plasmon resonance sensor chip, long-chain hydroxyalkyl thiols are adsorbed onto a gold surface as a monolayer, the monolayer's exposed hydroxy groups are activated with epichlorohydrin under basic conditions to form epoxides, a carboxylated dextran gel layer is covalently attached to the monolayer, and a proteinaceous binding partner of an analyte is first electrostatically adsorbed onto the dextran gel layer and then covalently attached thereto. This technique is described in an article by Lofas and Johnsson entitled, "A Novel Matrix on Gold Surfaces in Surface Plasmon Resonance Sensors for Fast and Efficient Covalent Immobilization of Ligands", J. Chem. Soc. Chem. Comm. 1526-1528 (1990). [0008] The effectiveness of this approach is hindered by several factors. First, covalent attachment of the proteinaceous binding partner to the gel can affect the binding partner's viability, or activity. Second, covalent attachment of the binding partner to the gel can not be effected with control over the orientation of the binding partner with respect to the surface of the chip (and, importantly, with respect to an analyte-containing medium). Third, non-specific interactions at the gel are promoted by the negative charge that it carries. [0009] According to another technique, a mixed monolayer of hydroxyl and biotin-terminated alkane thiols is prepared on a gold surface, streptavidin is bound to the surface-bound biotin, and biotin-labeled proteins, that are binding partners of analytes, then are attached to empty sites on the streptavidin. However, because biotin must be covalently attached to the protein, this approach lacks control over orientation of the binding partner with respect to the analyte medium, and inactivation of the proteinaceous binding partner due to the formation of covalent linkage can occur. This technique is described in an article by Spinke, Liley, Guder, Angermaier, and Knoll entitled, "Molecular Recognition at Self-Assembled Monolayers: The Construction of Multicomponent Multilayers", Langmuir, 9, 1821-1825 (1993). [0010] Accordingly, a general purpose of the present invention is to provide an easily-synthesized chemical species that readily adheres to a surface, and that facilitates surface immobilization of a binding partner of a molecule desirably captured at the surface with a high degree of sensitivity and minimal to zero non-specific binding. It is another purpose of the invention to provide an article with a surface having a high degree of sensitivity for a biological molecule. Another purpose of the invention is to provide a method of capturing a biological molecule, for example at a biosensor surface, by exploiting biological binding interactions that are extremely sensitive to molecular conformation and molecular orientation. Nomenclature [0011] The following definitions are provided to facilitate a clear understanding of the present invention. [0012] The term, "chelating agent" refers to an organic molecule having unshared electron pairs available for donation to a metal ion. The metal ion is in this way coordinated by the chelating agent. Two or more neighboring amino acids can act as a chelating agent. [0013] The terms, "bidentate chelating agent", "tridentate chelating agent", and "quadradentate chelating agent" refer to chelating agents having, respectively, two, three, and four electron pairs readily available for simultaneous donation to a metal ion coordinated by the chelating agent. [0014] The term "biological binding" refers to the interaction between a corresponding pair of molecules that exhibit mutual affinity or binding capacity, typically specific or non-specific binding or interaction, including biochemical, physiological, and/or pharmaceutical interactions. Biological binding defines a type of interaction that occurs between pairs of molecules including proteins, nucleic acids, glycoproteins, carbohydrates, hormones and the like. Specific examples include antibody/antigen, antibody/hapten, enzyme/substrate, enzyme/inhibitor, enzyme/cofactor, binding protein/substrate, carrier protein/substrate, lectin/carbohydrate, receptor/hormone, receptor/effector, complementary strands of nucleic acid, protein/nucleic acid repressor/inducer, ligand/cell surface receptor, virus/ligand, etc. [0015] The term "binding partner" refers to a molecule that can undergo biological binding with a particular biological molecule. For example, Protein A is a binding partner of the biological molecule IgG, and vice versa. [0016] The term "biological molecule" refers to a molecule that can undergo biological binding with a particular biological binding partner. [0017] The term "recognition region" refers to an area of a binding partner that recognizes a corresponding biological molecule and that facilitates biological binding with the molecule, and also refers to the corresponding region on the biological molecule. Recognition regions are typified by sequences of amino acids, molecular domains that promote van der Waals interactions, areas of corresponding molecules that interact physically as a molecular "lock and key", and the like. [0018] The term "coordination site" refers to a point on a metal ion that can accept an electron pair donated, for example, by a chelating agent. [0019] The term "free coordination site" refers to a coordination site on a metal ion that is occupied by a water molecule or other species that is weakly donating relative to a polyamino acid tag, such as a histidine tag. [0020] The term "coordination number" refers to the number of coordination sites on a metal ion that are available for accepting an electron pair. Continue reading... Full patent description for Molecular recognition at surfaces derivatized with self-assembled monolayers Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Molecular recognition at surfaces derivatized with self-assembled monolayers patent application. Patent Applications in related categories: 20080182236 - Asthma susceptibility locus - The present invention describes a susceptibility locus which is functionally related to asthma. The locus maps within human chromosome 7p15-p14. The invention also describes a novel human gene, GPRA. The invention provides diagnostic methods and materials for analysing allelic variation in said locus and the GPRA gene. The invention also ... 20080182237 - Lung cancer-related nucleic acids - Described are polynucleotides associated with lung cancer. The polynucleotides are miRNAs, miRNA precursors, and associated nucleic acids. Methods and compositions are described that can be used for diagnosis, prognosis, and treatment of lung cancer. Also described are methods that can be used to identify modulators of the disease-associated polynucleotides. Also ... ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Molecular recognition at surfaces derivatized with self-assembled monolayers or other areas of interest. ### Previous Patent Application: Microarrays utilizing hydrogels Next Patent Application: Non-invasive prenatal genetic diagnosis using transcervical cells Industry Class: Chemistry: molecular biology and microbiology ### FreshPatents.com Support Thank you for viewing the Molecular recognition at surfaces derivatized with self-assembled monolayers patent info. IP-related news and info Results in 0.31852 seconds Other interesting Feshpatents.com categories: Accenture , Agouron Pharmaceuticals , Amgen , AT&T , Bausch & Lomb , Callaway Golf |
||
