Patents Represented by Attorney Cynthia R. Moore
  • Patent number: 7651762
    Abstract: Articles of manufacture and devices and methods of forming and using the same are provided, wherein the article comprises a porous inorganic substrate contained in or bounded by a support made from an inorganic material are provided, wherein said porous substrate and support are heated to a temperature effective to shrink the support onto the porous substrate such that liquid tight contact is formed between the porous substrate and the support. In a preferred aspect, the porous inorganic substrate has a porosity of at least 5%, and is a porous monolith formed using a sol-gel method. The articles thus formed provide a confined fluid flow through the porous substrate, providing superior performance in separations, catalysis, filtration, and the like.
    Type: Grant
    Filed: March 13, 2007
    Date of Patent: January 26, 2010
    Assignee: Varian, Inc.
    Inventors: Dengfeng Xu, Robert Lee Grenz
  • Patent number: 7628915
    Abstract: A composition for use in chromatography is provided comprising a substrate modified with a metal-cyano bonded phase. This novel cyano bonded phase provides superior performance in high performance liquid chromatography (HPLC) and provides superior selectivity, improved peak shape for basic analytes, and the ability of provide rapid separation with outstanding resolution. The composition exhibits improved storage stability, and is chemically stable over a range of pH from 1.5 to 7.5 mobile phase conditions and for more than 2000 multiple injections. A baseline separation of eight tricyclic antidepressants was achieved in less than four minutes using an isocratic mobile phase with the metal-cyano bonded phase of the present invention, compared to the long retention times and poor separation observed for traditional cyano bonded phase. The composition of this invention is particularly useful in a wide variety of chromatographic applications.
    Type: Grant
    Filed: December 8, 2006
    Date of Patent: December 8, 2009
    Assignee: Varian, Inc.
    Inventors: Guang Qing Li, Yonglong Andrew Li
  • Patent number: 7595026
    Abstract: Solid phase extraction devices for sample preparation are disclosed, comprising a hollow conical tube having one narrower opening and one broader opening, wherein the narrower opening of the tube contains a solid phase extraction material comprising a functionalized monolithic sorbent, and wherein the solid phase extraction device is prepared by a combination of reduced pressure, positive pressure and mechanical compaction. The solid phase extraction devices are adapted for preparation of small sample volumes, and provide excellent recovery of analytes and good flow characteristics. Methods for preparing and using the solid phase extraction devices are disclosed.
    Type: Grant
    Filed: May 28, 2004
    Date of Patent: September 29, 2009
    Assignee: Varian, Inc.
    Inventors: William C. Hudson, Wilford C. Downs
  • Patent number: 7468281
    Abstract: Simultaneous sample purification, enrichment and analysis of pharmaceuticals, illicit drugs, pollutants, biotechnological products, synthetic organic reaction products and food/flavor ingredients from complex matrices can be performed using porous hollow fiber or porous-disk liquid-membrane devices. The devices are part of a multi-well (e.g. 96-well) plate. The devices can be used for selective separation and enrichment of complex mixtures containing trace levels of analytes, and can be used in tandem with analytical instruments which routinely handle multiple samples under high throughput screening conditions. A multi-well/multi-vial plate can into state-of-the-art HPLC or GC sampling systems or LC/MS or GC/MS instruments. Samples can be enriched several orders of magnitude and can directly be withdrawn from the fiber and injected into the chromatographic instruments. Alternatively, these enriched samples can be introduced directly into MS, CE or other detection devices.
    Type: Grant
    Filed: April 25, 2002
    Date of Patent: December 23, 2008
    Assignee: Varian, Inc.
    Inventors: Krishna Kallury, Joy Fan, Knut Rasmussen, Stig Pedersen-Bjergaard
  • Patent number: 7378035
    Abstract: The present invention relates to a material containing ionic groups that form an ionic pair with a free radical catalyst. In particular, the invention relates to materials that are magnetic, and to the methods of forming such materials. For example, a method of forming paramagnetic particles is disclosed, the method comprising contacting a substance having cationic groups with an aqueous solution of Fe3+ so that all the cationic groups are exchanged for Fe3+, adjusting the pH of the solution to between 9 and 10, to form Fe(III) hydroxide, reducing a portion of the Fe(III) hydroxide to Fe(II) hydroxide to obtain a blend of the Fe(III) hydroxide the Fe(II) hydroxide, and crystallizing the two iron hydroxides to form paramagnetic particles comprising magnetite. The invention also discloses the formation of polymers from the ionic groups within the material. Various applications of the resulting materials are also disclosed.
    Type: Grant
    Filed: November 3, 2005
    Date of Patent: May 27, 2008
    Assignee: Polymer Laboratories Limited
    Inventor: Graham Margetts
  • Patent number: 7056858
    Abstract: A polymeric sorbent that can be employed in the extraction and purification of polar and nonpolar molecules from a complex media (e.g. pharmaceuticals from biological matrices) by solid phase extraction (SPE). The sorbent exhibits a strong capacity for the retention of polar molecules and can facilitate the recovery of compounds possessing a range of polarities while furnishing clean extracts showing low ion suppression. The polymer is wettable and remains wetted over long periods of time.
    Type: Grant
    Filed: June 16, 2005
    Date of Patent: June 6, 2006
    Assignee: Varian, Inc.
    Inventors: Krishna M. R. Kallury, David C. Jones, Vipul J. Shah