Abstract: Ultrasound contrast agents comprising microbubbles of biocompatible gas, e.g. a sulphur halide or a perfluorocarbon, stabilized by opsonisable amphiphilic material, e.g. a membrane-forming lipid such as a phospholipid, especially a negatively charged phospholipid such as a phosphatidylserine, may exhibit prolonged contrast-generating residence time in the liver following intravenous administration.

Abstract: This invention relates generally to non-ionic X-ray contrast agents. It further relates to the synthesis of iodixanol. In particular, it relates to alternative dimerisation reagents in the conversion of 5-acetamido-N,N?-bis(2,3-dihydroxypropyl)-2,4,6-triiodoisophthalamide (“Compound A”) to iodixanol.

Abstract: Microbubble dispersions stabilised by phospholipids predominantly comprising molecules which individually have an overall net charge exhibit advantageous stability, rendering them useful as efficacious contrast agents. An improved process for preparing microbubble-containing contrast agents is also disclosed, this comprising lyophilising an aqueous dispersion of gas microbubbles stabilised by one or more membrane-forming lipids to yield a dried product which may be reconstituted in an injectable carrier liquid to generate a microbubble-containing contrast agent.

Abstract: Microbubble dispersions stabilised by phospholipids predominantly comprising molecules which individually have an overall net charge exhibit advantageous stability, rendering them useful as efficacious contrast agents. An improved process for preparing microbubble-containing contrast agents is also disclosed, this comprising lyophilising an aqueous dispersion of gas microbubbles stabilised by one or more membrane-forming lipids to yield a dried product which may be reconstituted in an injectable carrier liquid to generate a microbubble-containing contrast agent.

Abstract: The invention provides a method of contrast agent drug candidate selection which involves: (i) obtaining a combinatorial library comprising an admixture of potential contrast agent drug candidates each incorporating a reporter moiety which is detectable in the animate human or non-human animal body (e.g. mammalian, avian or reptilian body), said library comprising a plurality of said reporter moieties which are interdistinguishably detectable in said body; (ii) administering said library to an animate human or non-human animal body; (iii) identifying in vivo one or more of said reporter moieties which has a desired distribution and/or elimination pattern in said body and thereby identifying a member of said library which has said pattern site or a sub-set of said library which contains a member of said library which has said pattern.

Abstract: Ultrasound contrast agents comprising microbubbles of biocompatible gas, e.g. a sulphur halide or a perfluorocarbon, stabilized by opsonisable amphiphilic material, e.g. a membrane-forming lipid such as a phospholipid, especially a negatively charged phospholipid such as a phosphatidylserine, may exhibit prolonged contrast-generating residence time in the liver following intravenous administration.

Abstract: The stability of phospholipid compositions is enhanced by the inclusion of a buffer system comprising ammonia or a water soluble amine having a pH at 15° C. of less than or equal to 9.5.

Abstract: The invention provides low viscosity iodinated aryl compounds, useful as X-ray contrast agents, of formula C6R6 wherein three non-adjacent R groups are iodine and the remaining R groups are non-ionic, hydrophilic moieties, said compound being water soluble at 20° C. to a concentration of at least 350 mgl/ml and which in aqueous solution at 20° C. at a concentration of 350 mgl/ml has a viscosity no greater than 13.8 mPas.

Abstract: Oil-in-water emulsions in which the oil phase comprises condensed or dissolved oil-soluble gas/fluid or gas precursor are useful as ultrasound contrast agents. Such products contain insignificant amounts of free gas bubbles or microbubbles in their stored form and exhibit good stability, but may be designed to promote rapid microbubble generation immediately before or upon administration.

Abstract: Microparticulate contrast agents comprising gas or a gas precursor encapsulated by a non-polymeric and non-polymerisable wall-forming material are readily characterisable materials exhibiting surprising structural integrity and stability.

Abstract: Microbubble dispersions stabilized by phospholipids predominantly comprising molecules which individually have an overall net charge exhibit advantageous stability, rendering them useful as efficacious contrast agents. An improved process for preparing microbubble-containing contrast agents is also disclosed, this comprising lyophilising an aqueous dispersion of gas microbubbles stabilized by one or more membrane-forming lipids to yield a dried product which may be reconstituted in an injectable carrier liquid to generate a microbubble-containing contrast agent.

Abstract: Microbubble dispersions stabilised by phospholipids predominantly comprising molecules which individually have an overall net charge exhibit advantageous stability, rendering them useful as efficacious contrast agents. An improved process for preparing microbubble-containing contrast agents is also disclosed, this comprising lyophilising an aqueous dispersion of gas microbubbles stabilised by one or more membrane-forming lipids to yield a dried product which may be reconstituted in an injectable carrier liquid to generate a microbubble-containing contrast agent.

Abstract: Microbubble dispersions stabilised by phospholipids predominantly comprising molecules which individually have an overall net charge exhibit advantageous stability, rendering them useful both as efficacious contrast agents per se and as intermediates in the preparation of contrast agents wherein the phospholipids are crosslinked or polymerised. An improved process for preparing microbubble-containing contrast agents is also disclosed, this comprising lyophilising an aqueous dispersion of gas microbubbles stabilised by one or more membrane-forming lipids to yield a dried product which may be reconstituted in an injectable carrier liquid to generate a microbubble-containing contrast agent.

Abstract: Ultrasound contrast agents having microbubbles of gas or a gas precursor encapsulated by non-proteinaceous crosslinked or polymerised amphiphilic moieties, e.g. in the form of micelles, exhibit good stability in vivo upon administration and may if desired incorporate biodegradable linkages so as to possess particular desired levels of biodegradability.

Abstract: The invention provides low viscosity iodinated aryl compounds, useful as X-ray contrast agents, of formula I ##STR1## (wherein n is 0 or 1, and where n is 1 each C.sub.6 R.sub.5 moeity may be the same or different; each group R is a hydrogen atom, an iodine atom or a hydrophilic moiety M or M.sub.1, two or three non-adjacent R groups in each C.sub.6 R.sub.5 moiety being iodine and at least one, and preferably two or three, R groups in each C.sub.6 R.sub.5 moiety being M or M.sub.1 moieties; X denotes a bond or a group providing a 1 to 7 atom chain linking two C.sub.6 R.sub.5 moieties or, where n is 0, X denotes a group R; each M independently is a non-ionic hydrophilic moiety; and each M.sub.1 independently represents a C.sub.1-4 alkyl group substituted by at least one hydroxyl group and optionally linked to the phenyl ring via a carbonyl, sulphone or sulphoxide group, at least one R group being an M.sub.1 moiety; with the proviso that where n is zero either at least one M.sub.

Abstract: Novel extended polymer surfactants comprising a methoxy-terminated polyethylene glycol hydrophilic block acylated with a hydrophobic moiety comprising a chain of at least two fatty acid units, e.g. an acyloxyacyl group such as 16-hexadecanoyloxyhexadecanoyl, are useful in the preparation of polymer-based gas-containing contrast agents by emulsion techniques.

Abstract: The present invention provides a polyethylene glycol (PEG) ester surfactant comprising at least one polyethylene glycol moiety and at least one fatty acyl moiety characterized in that said moieties are linked by a linkage incorporating a biodegradable methylene diester unit of formula (I)--CO.O.C(R.sup.1)(R.sup.2).O.CO-- (I)where R.sup.1 and R.sup.2 may, for example, each be a hydrogen atom or a monovalent organic group attached through a carbon atom or R.sup.1 and R.sup.2 together may, for example, form a divalent organic group attached through carbon atoms.

Abstract: The present invention provides a polychelant compound of formula (VII), (wherein each X which may be the same or different is NZ, O or S, at least two Xs being NZ; B is (CR.sup.1 Y) or --N(CR.sup.1.sub.2 Y)--; each Z is a group R.sup.1 or a group CR.sup.1.sub.2 Y, at least one Z being a group CR.sup.1.sub.2 Y; each Y is a group CO.sub.2 H, PO.sub.3 H, SO.sub.3 H, CONR.sup.1.sub.2, CON(OR.sup.1)R.sup.1, CNS or CONR.sup.1 NR.sup.1.sub.2 ; m is 0 or 1 or 2; each n is 2 or 3; q is 0 or 1 when B is (CR.sup.1 Y) and 2 when B is N(CR.sup.1.sub.2 Y); p is an integer having a value of at least 2; each R.sup.1 which may be the same or different is a hydrogen atom or an alkyl, aryl or aralkyl group optionally substituted by one or more hydroxy or alkoxy groups, or two R.sup.1 groups on ring atoms or in Z groups together represent a linker group L; each L which may be the same or different represents a bond or an organic linker group having a molecular weight of less than 1000 and salts and chelates thereof.

Abstract: An x-ray contrast medium containing a multinuclear complex of the formula (M.sub.6 (.mu..sub.3 B).sub.8 A.sub.v).sub.x L.sub.w, wherein M is Mo, W, Re Tc, V, Nb, Ta, Ru, or Fe; .mu..sub.3 B represent a tridentate bridging atom; A is a non-bridging atom; L is a ligand coordinately bonded to at least one M atom; x is a positive integer; and v and w are independently zero or positive integers.

Abstract: The present invention relates to polymer-based gas-containing contrast agents in which microbubbles of gas are encapsulated by non-polymerizable wall-forming block or graft copolymer surfactants. The polymer surfactants are preferably biodegradable and include block and graft copolymers containing linkages of formula (I):--(O).sub.m --CO--O--C(R.sup.1 R.sup.2)--O--CO--(O).sub.n --(I)where R.sup.1 and R.sup.2 each represent a hydrogen atom or a carbon-attached monovalent organic group, or R.sup.1 and R.sup.2 together form a carbon-attached divalent organic group and m and n are each zero or 1.