Abstract: A process for purification of water soluble polymers is provided. A polymer of interest can be separated from a mixture of polymers, provided the polymer of interest differs from other polymers in the mixture in the number of reactive terminal groups. The process involves derivatizing polymers at the reactive terminal groups with a derivatizing molecule, bearing either (i) two or three cationic or anionic ionizable groups, and a group capable of covalent bonding to the reactive terminal groups or (ii) three or four ionizable groups, at least one of which is capable of covalent bonding to the reactive terminal groups; followed by ion exchange. The process allows removal of PEG from MPEG, and can be used for polymers having an average size greater than 9,000 Da Derivatization may be reversible in order to allow re-use of recovered contaminant polymers.

Abstract: The present invention relates to a method of preparing modified polypeptides, by linking a target polypeptide to a carrier molecule that is designed to bear one or more water-soluble polymer molecules, via protein trans-splicing. The polymer molecules can be attached to the carrier molecule either before or after ligation to the target polypeptide. Novel protein trans-splicing elements (known as “split inteins”) and trans-splicing partners are also provided.

Abstract: A process for purification of water soluble polymers is provided. A polymer of interest can be separated from a mixture of polymers, provided the polymer of interest differs from other polymers in the mixture in the number of reactive terminal groups. The process involves derivatizing polymers at the reactive terminal groups with a derivatizing molecule, bearing either (i) two or three cationic or anionic ionizable groups, and a group capable of covalent bonding to the reactive terminal groups or (ii) three or four ionizable groups, at least one of which is capable of covalent bonding to the reactive terminal groups; followed by ion exchange. The process allows removal of PEG from MPEG, and can be used for polymers having an average size greater than 9,000 Da Derivatization may be reversible in order to allow re-use of recovered contaminant polymers.

Abstract: This invention describes a method for the rapid identification of the presence of microorganisms in a sample. Briefly, in the method of this invention the sample container is divided into a plurality of discrete zones, each of which can be separately monitored for microbial presence. When a sample is placed into this container, detection is simplified as the volume monitored is low (as compared with the sample); since microbial detection is a concentration dependent phenomenon, the speed with which the presence of microbial contamination can be detected is increased.

Abstract: This invention presents methods for detection and evaluation of metabolic activity of microorganisms based upon their ability to consume dissolved oxygen. The methods utilize a fluorescence detection system which makes use of the sensitivity of the fluorescent emission of certain compounds to the presence of oxygen, which quenches (diminishes) the compound's fluorescent emission in a concentration dependent manner. Respiring microorganisms will affect the oxygen concentration of a liquid medium in which they are immersed. Thus, this invention provides a convenient system to gather information on the presence, identification and metabolic activity of microorganisms by determining their effect on the oxygen concentration of the media in which they are present.

Abstract: A method for receiving, distributing and storing a sample into numerous aliquots of small volume without air entrapment and with retention of aliquots when the device is manipulated and for the treatment of any or all of the aliquots with the same or different reagents and/or other chemical additives.

Abstract: The present invention is a device and method for breaking an ampoule. In particular, the device is preferably for use in an apparatus for collecting and transporting biological specimens. The device comprises a guard arrangement that surrounds a frangible ampoule. With appropriate force applied to the guard arrangement, the frangible ampoule is ruptured.

Abstract: The present invention is a device which allows for receiving, distributing and storing a sample into numerous aliquots of small volume without air entrapment and with retention of aliquots when the device is manipulated. The device allows for the treatment of any or all of the aliquots with the same or different reagents and/or other chemical additives. The device comprises a housing for containing a body for guiding a sample into a plurality of wells without the need for pipetting aids, without multiple manipulations, without the retention of air and for retaining sample in the wells.

Abstract: A microbiological culture collection and transport device maintains viable organisms for periods of time longer than possible with existing sampling devices. It also allows recovery of detectable antigen at levels not achievable with conventional swabs. The new device has a sterile swabbing tip made with a non-toxic polyurethane foam having open cells at its exposed surface. It does not require a transport medium and can be used dry. The device may further include a sample inoculator to distribute organisms collected onto a solid or semi solid medium. Methods for collecting and transporting microbiological specimens and for recovering detectable antigen are also described.

Abstract: A microbiological culture collection and transport device maintains viable organisms for periods of time longer than possible with existing sampling devices. It also allows recovery of detectable antigen at levels not achievable with conventional swabs. The new device has a sterile swabbing tip made with a non-toxic polyurethane foam having open cells at its exposed surface. It does not require a transport medium and can be used dry. The device may further include a sample inoculator to distribute organisms collected onto a solid or semi solid medium. Methods for collecting and transporting microbiological specimens and for recovering detectable antigen are also described.

Abstract: A self-contained specimen collecting and transporting unit is provided which has all of the advantages of the known specimen collecting and transporting units and which is characterized by the ability to preserve microorganisms during the transporting thereof in the transporting unit. The improved specimen collecting and transporting unit has a pledget composed of carbon fiber. The use of a carbon fiber pledget has been found to have a synergistic effect in preserving the viability of microorganisms which are obtained by use of the swab of the specimen collecting and transporting unit.

Abstract: An assay method suitable for antigens (or haptens) including proteins and polypeptides utilizing antibodies for the unknown protein or polypeptide in which the antibodies are covalently bound to water insoluble hydrophilic polymeric particles. Appropriate fluorescently labeled immune reactants are introduced during the method and together with the unknown antigen are immunologically bound, directly or indirectly, to the particles for separation from the reaction liquid. The particles have a size of about 0.1-10 microns and can be resuspended for direct measurement of the fluorescent labels in a fluorometer from which the unknown can be determined.

Abstract: A method and apparatus for casting gel slabs useful in electrophoretic procedures is provided. Glass plates are horizontally positioned in parallel a capillary action-inducing distance apart to form an unsealed space. Gel-forming liquid, e.g. polyacrylamide is introduced between the plates and fills the space by capillary action. The surface tension of the gel-forming liquid is utilized to constrain the liquid between the plates at the unsealed or open edges. Once the desired sized space is filled the gel is formed by polymerization and/or cooling. Where an open faced gel slab is desired one of the plates is separated from the gel layer.

Abstract: Insoluble cationic acrylamide copolymers for use as cell growth carriers and a novel copolymer of dimethylaminopropylmethacrylamide, acrylamide and methylene-bis-acrylamide useful as both a carrier for cell growth and as a medium for ion exchange chromatography of aqueous protein solutions.

Abstract: An assay method suitable for antigens (or haptens) including proteins and polypeptides utilizing antibodies for the unknown protein or polypeptide in which the antibodies are covalently bound to water insoluble hydrophylic polymeric particles. Appropriate fluorescently labeled immune reactants are introduced during the method and together with the unknown antigen are immunologically bound, directly or indirectly, to the particles for separation from the reaction liquid. The particles have a size of about 0.1-10 microns and can be resuspended for direct measurement of the fluorescent labels in a fluorometer from which the unknown can be determined.

Abstract: Electrophoresis apparatus having a housing, a substantially horizontal cooling bed within the housing for supporting and cooling a medium during electrophoresis, a transparent cover overlying the bed, and first and second electrode troughs along opposed sides of the bed. A condenser coil has an open central area greater than the area of the bed and overlies the bed with the open area located above a vertical projection of the bed. Major segments of the condenser coil overlie the electrode troughs. The condenser coil and the cooling bed are arranged for serial fluid flow with coolant fluid introduced into the condenser coil and withdrawn from the cooling bed. The cooling bed itself has first and second generally parallel plates spaced apart by a core which defines a tortuous path for fluid flow. One of the plates has a higher thermal conductivity than the other. By inverting the cooling bed, differing cooling rates can be achieved.

Abstract: The method of this invention is characterized by the use of hydrolyzed cross-linked polyacrylamide particles to which have been bonded, by means of covalent bonds, antibiodies against the thyroid hormone to be determined. The particles selected are of a size which forms a stable hydrophyllic suspension. In the preferred embodiment a measured quantity of unextracted human serum is mixed together with a blocking agent in an amount sufficient to displace the thyroid hormone to be measured from thyroxine binding globulin (TBG), a radioactively labeled thyroid hormone of the type to be measured, and the antibody-polyacrylamide complex. The hormone to be measured is displaced by the blocking agent followed by the competitive binding of the labeled and unlabeled hormone to the antibody-polyacrylamide particles. The particles are readily separated from the sample liquid and the radioactivity of the particle material and/or in the liquid is determined.

Abstract: Electrophoretic gels are destained between two layers of ion exchange resin. Electrical current is passed from one layer of resin to the other through the gel in an electrically low-conductive surrounding medium such as de-ionized water. Virtually all of the current goes through the gel resulting in the highly efficient destaining technique.

Abstract: Gels for electrophoresis such as polyacrylamide gels are formed in a neutral pH medium containing a salt solution of preselected concentration. This salt is incorporated in the gel and in subsequent use in electrophoresis is displaced upon application of an electrical potential (direct current) by ionic species which form a pH buffer in the gel. Prior to introduction of the buffer, the gel containing the neutral salt is storage stable for prolonged periods of time. The gel is reproducible since it is always formed under the same conditions and the buffer only thereafter introduced.