Abstract: Phospholipid conjugate compounds derived from cardiac glycosides and sters useful in liposome immunoassays are disclosed as well as their method of preparation.

Abstract: Phospholipid conjugate compounds derived from cardiac glycosides and steroids useful in liposome immunoassays are disclosed as well as their method of preparation.

Abstract: A method and reagent composition provide for the removal or blocking of serum interferences in liposome immunoassays. A carrier or liposome exhibiting at least one domain of phosphoryl ester groupings different from those of the marker liposome is introduced into the reaction mixture, whereby endogenous interfering species competitively bind to such carrier or liposome rather than to the marker liposome. Also, soluble phosphoryl ester groupings can be introduced into the reaction mixture which react with such endogenous species and further reduce serum interferences.

Abstract: A specific binding assay composition and method for determining a ligand in a sample are disclosed. The composition comprises (a) a binding partner for the ligand; (b) a detection system which has at least two components; (c) a selectively accessible vesicle having a surface-incorporated ligand or ligand analog and a first component of the detection system therein; (d) a substance which modifies vesicle accessibility in response to binding of surface-associated ligand or ligand analog and binding partner; and (e) at least one additional component of the detection system which is reactive with the first component to produce a detectable response which is reduced by association of the binding partner and vesicle modifying substance with the variabily accessible vesicle. A decrease in signal is measured upon reaction as compared to the signal of unreacted vesicles.

Abstract: Disclosed is a specific binding assay composition and method for determining a ligand in a sample. The composition comprises (a) a binding partner for the ligand; (b) a detection system which has at least two components; (c) a selectively accessible vesicle having a surface-incorporated ligand or ligand analog and a first component of the detection system therein; (d) a substance which modifies vesicle accessibility in response to binding of surface-incorporated ligand or ligand analog and the binding partner; (e) at least one additional component of the detection system which is reactive with the first component to produce a detectable response; and (f) at least one surfactant which does not modify vesicle accessibility. The composition and method are suitable for use with automated, including continuous flow-type, analyzers.

Abstract: Novel substrates for monitoring of catalytic activity resulting in hydrolytic release of products which can be readily detected by spectrophotometric or fluorometric means are provided. The substrates have the general formula: ##STR1## wherein B is a nucleotide base capable of assisting in hydrolysis of the phosphate ester at the 3'-position; R is a moiety selected from the group consisting of umbelliferonyl, 4-methylumbelliferonyl, 3-flavonyl, o-nitrophenyl, m-nitrophenyl, p-nitrophenyl, dinitrophenyl, cyanophenyl, acylphenyl, carboxyphenyl, phenylsulfonate, phenylsulfonyl and phenylsulfoxide; R' is a moiety selected from the group consisting of hydrogen, alkyl, alkenyl cycloalkyl, aryl, araalkyl, acyl, oxaalkyl, thioalkyl, oxacycloalkyl, and thiocycloalkyl and R" is hydrogen or a cation selected from the group consisting of calcium, barium, lithium, sodium, ammonium, substituted ammonium and pyridinium.

Abstract: Novel isocyanates such as, for example, blocked L-tyrosine methyl ester isocyanate, are reacted with compounds of biological, clinical interest or the like such as, for example, digoxin, to form derivatives receptive to tagging, as by radioliabeling. The tagged derivatives may then be employed to determine the presence of the compound of interest in nanomolar or even picomolar amounts by using clinical analysis techniques such as radioimmunoassay.

Abstract: Elastomeric high molecular weight alternating and random block copolymers are disclosed which comprise blocks of a soft carborane-siloxane elastomer and blocks of a high performance rigid polymer. Methods for preparing such block copolymers are also disclosed. These copolymers exhibit the advantages of high temperature elastomers while allowing the use of conventional thermoplastic fabrication techniques.

Abstract: Carborane-siloxane polymers are conveniently prepared by the polymerization of a carborane disilanol and either a silyl diamine, a ureido-silane, or a silyl dicarbamate. The resulting linear polymers are characterized by relatively high molecular weights and are elastomeric in nature. These gumstocks are compounded with suitable fillers and additives and fabricated into cured elastomeric articles. The carborane-siloxane elastomers exhibit excellent high temperature properties which render them especially useful for a wide variety of applications, such as gaskets, seals, wire and cable insulation and the like.

Abstract: Isocyanates are prepared directly from amines in a facile process which involves the reaction with halosilyl compounds to form novel halosilyl carbamates. The isocyanate may then be derived from the carbamate intermediate by gentle heating. In accordance with one aspect of the invention, isocyanates can be formed which contain a further reactive functional moiety, such as hydroxyl, amino, mercapto, nitro, sulfonamido, amido, carboxyl or the like.

Abstract: Novel isocyanates such as, for example, blocked L-tyrosine methyl ester isocyanate, are reacted with compounds of biological, clinical interest or the like such as, for example, digoxin, to form derivatives receptive to tagging, as by radiolabeling. The tagged derivatives may then be employed to determine the presence of the compound of interest in nanomolar or even picomolar amounts by using clinical analysis techniques such as radioimmunoassay.

Abstract: An apparatus and process are provided for the safe, economic and pollution-free exposure of articles to reactive gaseous fluids to alter their surface characteristics. The articles are exposed to one or more fluids which are transferred back and forth from a reaction chamber to a holding chamber. As the fluids are transferred they pass through a trap designed to remove reaction-by-products without affecting valuable reactant fluids. Since the fluids can be transferred under vacuum and the overall reaction can take place at relatively low temperatures, the process provides a convenient and safe method for handling reactive fluids. The process is particularly useful for the halogenation, for example fluorination, of a variety of articles, such as plastic containers, aerosol bottles and films to improve their barrier resistance to solvents and gases.

Abstract: Isocyanates are prepared directly from amines in a facile process which involves the reaction with halosilyl compounds to form novel halosilyl carbamates. The isocyanate may then be derived from the carbamate intermediate by gentle heating. In accordance with one aspect of the invention, isocyanates can be formed which contain a further reactive functional moiety, such as hydroxyl, amino, mercapto, nitro, sulfonamido, amido, carboxyl or the like.

Abstract: An apparatus and process are provided for the safe, economic and pollution-free exposure of articles to reactive gaseous fluids to alter their surface characteristics. The articles are exposed to one or more fluids which are transferred back and forth from a reaction chamber to a holding chamber. As the fluids are transferred they pass through a trap designed to remove reaction-by-products without affecting valuable reactant fluids. Since the fluids can be transferred under vacuum and the overall reaction can take place at relatively low temperatures, the process provides a convenient and safe method for handling reactive fluids. The process is particularly useful for the halogenation, for example fluorination, of a variety of articles, such as plastic containers, aerosol bottles and films to improve their barrier resistance to solvents and gases.