Abstract: A three-dimensional printer uses inkjet-type printheads to rapidly prototype, or print, a three-dimensional model. A powder feeder includes a conveyor system and a metering system to deliver powder to a build area in measured quantities. The powder feeder also includes a vacuum system for loading powder into a feed reservoir or chamber. The vacuum system can also be used to cleanup excess powder. Other powder control features include powder gutters and magnetic powder plows. During printing, a cleaning system operates to remove powder from the printheads. In the event of a printhead or jet failure, the failure can be detected and corrective measures taken automatically. After printing, the model can be depowdered and infiltrated in an enclosure.

Abstract: The invention relates to apparatus and methods for producing three-dimensional objects and auxiliary systems used in conjunction with the aforementioned apparatus and methods. The apparatus and methods involve 3D printing and servicing of the equipment used in the associated 3D printer.

Abstract: The invention relates to apparatus and methods for producing three-dimensional objects and auxiliary systems used in conjunction with the aforementioned apparatus and methods. The apparatus and methods involve 3D printing and servicing of the equipment used in the associated 3D printer.

Abstract: The disclosed methods, apparatus and compositions are of use for nucleic acid sequencing. More particularly, the methods and apparatus concern sequencing single molecules of single stranded DNA or RNA by exposing the molecule to exonuclease activity, removing free nucleotides one at a time from one end of the nucleic acid, and identifying the released nucleotides by Raman spectroscopy or FRET.

Abstract: Methods and apparatus are provided for assaying cell samples, which may be living cells, using probes labeled with composite organic-inorganic nanoparticles (COINs) and microspheres with COINs embedded within a polymer matrix to which the probe moiety is attached. COINs intrinsically produce SERS signals upon laser irradiation, making COIN-labeled probes particularly suitable in a variety of methods for assaying cells, including biological molecules that may be contained on or within cells, most of which are not inherently Raman-active. The invention provides variations of the sandwich immunoassay employing both specific and degenerate binding, methods for reverse phase assay of tissue samples and cell microstructures, in solution displacement and competition assays, and the like. Systems and chips useful for practicing the invention assays are also provided.

Abstract: The methods and apparatus 100 disclosed herein are of use for sequencing and/or identifying nucleic acids 230, 310. Nucleic acids 230, 310 containing labeled nucleotides 235, 245, 315 may be synthesized and passed through nanopores 255, 310. Detectors 257, 345 operably coupled to the nanopores 255, 310 may detect the labeled nucleotides 235, 245, 315. By determining the time intervals at which labeled nucleotides 235, 245, 315 are detected, distance maps 140 for each type of labeled nucleotide 235, 245, 315 may be compiled. The distance maps 140 in turn may be used to sequence 150 and/or identify 160 the nucleic acid 230, 310. In different embodiments of the invention, luminescent nucleotides 235, 245 or nanoparticles 315 may be detected using photodetectors 257 or electrical detectors 310. Apparatus 100 and sub-devices 200, 300 of use for nucleic acid 230, 310 sequencing 150 and/or identification 160 are also disclosed herein.

Abstract: Provided herein are methods and systems for detecting biomolecular binding events using gigahertz or terahertz radiation. The methods and systems use low-energy spectroscopy to detect biomolecular binding events between molecules in an aqueous solution. The detected biomolecular binding events include, for example, nucleic acid hybridizations, antibody/antigen binding, and receptor/ligand binding.

Abstract: The methods and apparatus disclosed herein concern nucleic acid sequencing by enhanced Raman spectroscopy. In certain embodiments of the invention, nucleotides are covalently attached to Raman labels before incorporation into a nucleic acid 13. Exonuclease 15 treatment of the labeled nucleic acid 13 results in the release of labeled nucleotides 16, 130, which are detected by Raman spectroscopy. In alternative embodiments of the invention, nucleotides 16, 130 released from a nucleic acid 13 by exonuclease 15 treatment are covalently cross-linked to silver or gold nanoparticles 140 and detected by surface enhanced Raman spectroscopy (SERS), surface enhanced resonance Raman spectroscopy (SERFS) and/or coherent anti-Stokes Raman spectroscopy (CARS). Other embodiments of the invention concern apparatus 10, 100, 210 for nucleic acid sequencing.

Abstract: The methods and apparatus 100 disclosed herein are of use for sequencing and/or identifying nucleic acids 230, 310. Nucleic acids 230, 310 containing labeled nucleotides 235, 245, 315 may be synthesized and passed through nanopores 255, 310. Detectors 257, 345 operably coupled to the nanopores 255, 310 may detect the labeled nucleotides 235, 245, 315. By determining the time intervals at which labeled nucleotides 235, 245, 315 are detected, distance maps 140 for each type of labeled nucleotide 235, 245, 315 may be compiled. The distance maps 140 in turn may be used to sequence 150 and/or identify 160 the nucleic acid 230, 310. In different embodiments of the invention, luminescent nucleotides 235, 245 or nanoparticles 315 may be detected using photodetectors 257 or electrical detectors 310. Apparatus 100 and sub-devices 200, 300 of use for nucleic acid 230, 310 sequencing 150 and/or identification 160 are also disclosed herein.

Abstract: The disclosed methods and apparatus concern Raman spectroscopy using metal coated nanocrystalline porous silicon substrates. Porous silicon substrates may be formed by anodic etching in dilute hydrofluoric acid. A thin coating of a Raman active metal, such as gold or silver, may be coated onto the porous silicon by cathodic electromigration or any known technique. In certain alternatives, the metal coated porous silicon substrate comprises a plasma-oxidized, dip and decomposed porous silicon substrate. The metal-coated substrate provides an extensive, metal rich environment for SERS, SERRS, hyper-Raman and/or CARS Raman spectroscopy. In certain alternatives, metal nanoparticles may be added to the metal-coated substrate to further enhance the Raman signals. Raman spectroscopy may be used to detect, identify and/or quantify a wide variety of analytes, using the disclosed methods and apparatus.

Abstract: Embodiments of the present invention provide devices and methods for detecting, identifying, distinguishing, and quantifying modifications to nucleic acids, proteins, and peptides using SERS and Raman spectroscopy. Applications of embodiments of the present invention include proteome wide modification profiling and analyses with applications in disease diagnosis, prognosis and drug efficacy studies, enzymatic activity profiling and assays.

Abstract: The disclosed methods, apparatus and compositions are of use for nucleic acid sequencing. More particularly, the methods and apparatus concern sequencing single molecules of single stranded DNA or RNA by exposing the molecule to exonuclease activity, removing free nucleotides one at a time from one end of the nucleic acid, and identifying the released nucleotides by Raman spectroscopy or FRET.

Abstract: The invention relates to methods and apparatus for fabricating a three-dimensional object from a representation of the object stored in memory. The apparatus includes a stationary build table for receiving successive layers of a build material and at least one movable printhead disposed above the build table. The printhead deposits a binding material in a predetermined pattern on each successive layer of the build material to form the three-dimensional object.

Abstract: The methods and apparatus, disclosed herein are of use for sequencing and/or identifying proteins, polypeptides and/or peptides. Proteins containing labeled amino acid residues may be synthesized and passed through nanopores. A detector operably coupled to a nanopore may detect labeled amino acid residues as they pass through the nanopore. Distance maps for each type of labeled amino acid residue may be compiled. The distance maps may be used to sequence and/or identify the protein. Apparatus of use for protein sequencing and/or identification is also disclosed herein. In alternative methods, other types of analytes may be analyzed by the same techniques.

Abstract: The methods and apparatus disclosed herein concern nucleic acid sequencing by enhanced Raman spectroscopy. In certain embodiments of the invention, nucleotides are covalently attached to Raman labels before incorporation into a nucleic acid 13. Exonuclease 15 treatment of the labeled nucleic acid 13 results in the release of labeled nucleotides 16, 130, which are detected by Raman spectroscopy. In alternative embodiments of the invention, nucleotides 16, 130 released from a nucleic acid 13 by exonuclease 15 treatment are covalently cross-linked to silver or gold nanoparticles 140 and detected by surface enhanced Raman spectroscopy (SERS), surface enhanced resonance Raman spectroscopy (SERRS) and/or coherent anti-Stokes Raman spectroscopy (CARS). Other embodiments of the invention concern apparatus 10, 100, 210 for nucleic acid sequencing.

Abstract: The methods and apparatus 300 disclosed herein concern Raman spectroscopy using metal coated nanocrystalline porous silicon substrates 240, 340. In certain embodiments of the invention, porous silicon substrates 110, 210 may be formed by anodic etching in dilute hydrofluoric acid 150. A thin coating of a Raman active metal, such as gold or silver, may be coated onto the porous silicon 110, 210 by cathodic electromigration or any known technique. The metal-coated substrate 240, 340 provides an extensive, metal rich environment for SERS, SERRS, hyper-Raman and/or CARS Raman spectroscopy. In certain embodiments of the invention, metal nanoparticles may be added to the metal-coated substrate 240, 340 to further enhance the Raman signals. Raman spectroscopy may be used to detect, identify and/or quantify a wide variety of analytes, using the disclosed methods and apparatus 300.

Abstract: The invention provides methods for analyzing the protein content of a biological sample, for example to obtain a protein profile of a sample provided by a particular individual. The proteins and protein fragments in the sample are separated on the basis of chemical and/or physical properties and maintained in a separated state at discrete locations on a solid substrate or within a stream of flowing liquid. Raman spectra are then detected as produced by the separated proteins or fragments at the discrete locations such that a spectrum from a discrete location provides information about the structure or identity of one or more particular proteins or fragments at the discrete location. The proteins or fragments at discrete locations can be coated with a metal, such as gold or silver, and/or the separated proteins can be contacted with a chemical enhancer to provide SERS spectra. Method and kits for practicing the invention are also provided.

Abstract: The present methods and apparatus concern the detection and/or identification of target analytes using probe molecules. In various embodiments of the invention, the probes or analytes are attached to one or more cantilevers. Binding of a probe to an analyte results in deflection of the cantilever, detected by a detection unit. A counterbalancing force may be applied to restore the cantilever to its original position. The counterbalancing force may be magnetic, electrical or radiative. The detection unit and the mechanism generating the counterbalancing force may be operably coupled to an information processing and control unit, such as a computer. The computer may regulate a feedback loop that maintains the cantilever in a fixed position by balancing the deflecting force and the counterbalancing force. The concentration of analytes in a sample may be determined from the magnitude of the counterbalancing force required to maintain the cantilever in a fixed position.

Abstract: A nano-electrode or nano-wire may be etched centrally to form a gap between nano-electrode portions. The portions may ultimately constitute a single electron transistor. The source and drain formed from the electrode portions are self-aligned with one another. Using spacer technology, the gap between the electrodes may be made very small.

Abstract: Disclosed herein are methods, apparatuses, and systems for performing nucleic acid sequencing reactions and molecular binding reactions in a microfluidic channel. The methods, apparatuses, and systems can include a restriction barrier to restrict movement of a particle to which a nucleic acid is attached. Furthermore, the methods, apparatuses, and systems can include hydrodynamic focusing of a delivery flow. In addition, the methods, apparatuses, and systems can reduce non-specific interaction with a surface of the microfluidic channel by providing a protective flow between the surface and a delivery flow.