Medicine, in particular medications for treating blood losses, hypoxic and ishemic states, for improving a blood oxygen supply and for preserving isolated perfused organs and tissues. The inventive medical emulsion of perfluororganic compounds includes rapidly excretable perfluororganic compounds such as perfluordecalin, perfluoractilbromide, a perfluoroganic additive embodied in the form of a mixture of perfluorinated tertiary amines and phospholipids in the form of a water-salt dispersion. The perfluordecalin and perfluoractilbromide are contained in the composition of the rapidly excretable perfluororganic compounds at a ratio ranging from 10:1 to 1:10. The mixture of perfluorinated tertiary amines is embodied in the form of the mixture of perfluorotpripropylamine and the co-products thereof: cis- and trans-isomers perfluor-1-propyl 3,4-dimethylpirrolidone and perfluor-1-propyl-4-methhylpiperidine. The inventive method for producing the emulsion includes producing the water-salt dispersion of phospholipids, in homogenizing the perfluororganic compounds therein at a high pressure and in sterilization of the final emulsion. The storage life of the inventive emulsion in the unfrozen state thereof at a temperature of +4.degree. C. is equal to at least 6 months during which the biocompatibility of the emulsion with a biological medium (blood, plasma or serum) is preserved.

Description of the Invention

SUMMARY OF THE INVENTION

One object of this invention resides in increasing the stability of the emulsion and in improving the quality of the emulsion, i.e. in obtaining biocompatibility with the biological medium (blood, plasma or serum) with a storage of at least 6-12 months in the non-frozen state.

The emulsion according to this invention for medicinal purposes contains rapidly eliminated perfluorodecaline or perfluorooctylbromide and also a perfluorinated supplement and a phospholipid. This emulsion is characterized in that a composition of mixed perfluorodecaline and perfluorooctylbromide is used as rapidly eliminated component, and the perfluorinated supplement represents a mixture of perfluorinated tertiary amines, and the phospholipids are used as a dispersion in the water-salt medium.

The emulsion is further characterized in that the total concentration of fluorocarbon compounds is in the range of 2 to 40% by volume.

The emulsion is further characterized in that the composition contains the rapidly eliminated perfluorodecaline and perfluorooctylbromide in a ratio of 10:1 to 1:10, in that the perfluorinated supplement is 1% to 50% of the total content of the fluorocarbon compounds and contains cis- and trans-isomers of perfluoro-1-propyl-3,4-dimethylpyrrolidone and perfluoro-1-propyl-4-methylpiperidine and also additional perfluoro-N-methylcyclohexylpiperidine and coproducts thereof.

The emulsion is further characterized in that it contains a dispersion of the egg and soya phospholipids or a mixture of these lipids in the water-salt medium in the concentration of 0.2 to 5% by weight.

The emulsion is further characterized in that the phospholipid dispersion in the water-salt medium contains an adjuvant of 1 to 15% of the total content of the phospholipids. Vegetable oil is used as adjuvant and in fact soya, sunflower seed or ricinus oil or a mixture of these oils in the effective ratio as a twofold or threefold mixture.

The emulsion is further characterized in that the water-salt medium contains sodium salts and potassium salts of chlorides and phosphates and also the monosaccharide mannitol in the injection water and the concentration of the components in the water-salt medium has an osmotic pressure in the range of 100 to 350 mosmol/l.

The emulsion is further characterized in that the mean particle size does not exceed 0.2 .mu.m and is in the range of 0.06-0.2 .mu.m.

The production method of the emulsion according to this invention by homogenization is characterized in that the method contains a plurality of steps which include a phospholipid dispersion in the water-salt medium, homogenization in the phospholipid dispersion, heat sterilization of the produced emulsion and subsequent storage of at least 6 months in the non-frozen state at a temperature of +4.degree. C.

The production method according to the invention is further characterised in that the phospholipid dispersion in the water-salt medium is produced by homogenisation at a high pressure of at least 100 atm and with a subsequent sterilisation.

The production method according to the invention is further characterized in that the fluorocarbon compounds in the phospholipid dispersion are homogenized at a pressure of 300 to 650 atm.

The production method according to this invention is further characterized in that the phospholipid dispersion and emulsion are sterilized at a temperature of 100.degree. C.

DETAILED DESCRIPTION OF THE INVENTION

As is indicated above, the object of the invention resides in increasing the emulsion stability and improving the emulsion quality, i.e. in obtaining biocompatibility in the biological medium (blood, plasma or serum) with storage of 6-12 months in the non-frozen state. The term biocompatibility includes different variables and should be made precise relative to the emulsion. In the above-mentioned patents [8-11], there is understood by biocompatibility a relatively high elimination rate of the chosen PFCs, the ability to preserve the tissues and organs through which the emulsion is perfused and a comparatively low toxicity for animals (at least 2 volumes of throughflowing blood). These ideas are not mutually exclusive but do not reflect the first step, namely the cooperation of the particles with plasma and blood in the bloodstream. In this invention, the biocompatibility begins with the level of significance of the cooperation (reaction) of the emulsion with the biological medium (blood, plasma or serum). The results of this cooperation can be evaluated not only in vivo but also above all in tests in vitro according to the stabilization level of the emulsion with the influence of a series of factors which simulate damage to the absorption layer during storage and penetration of the emulsion into the bloodstream.

The quality and stability of the emulsions is normally characterized on the basis of particle size and in fact the mean particle average should not exceed 0.2-0.3 .mu.m. Such an approach is not adequate for biomedicinal, dispersed preparations for intravenous injection. This is based on the fact that the fluorocarbon particles cooperate as foreign material with proteins and molecules of other compounds found in the plasma and also with blood cells during penetration into the bloodstream. The general character of the cooperation depends upon the properties of the particle surface. The functional activity (gas transport function) of the emulsions depends substantially upon the compatibility of the surface of the emulsified particles with blood and plasma since a reaction cascade is initiated for example during system activation of the complement on the foreign surface, said reaction cascade being caused by vascular spasm and interference in the regional blood flow. It should also be noticed that the emulsion stability in vitro is greatly affected by the properties of the absorption layer of surfactants around the particles (strength, topography of the surface etc.). In the sense of what has just been mentioned, the problem of emulsion stability can be resolved only by normal chemical colloid methods of particle examination without evaluation of the structural particularities. Development in this respect of simple methods and approaches which can provide information about the particle size and totality of the particle structure is extremely topical. The term structure itself is thereby intended to be made precise with respect to emulsions.

Progress in the examination of emulsion stability in vitro and in vivo is connected to the broadening and extension of the term structure and also upon the development of examination methods of the structure. The term stability of a preparation or of a substance is determined by the stability of the properties of the diverse preparation or of this substance. The parameters determining the properties of the emulsion do not adequately characterize the stability of the emulsion. In tests on this side, ideas about the stability of the emulsions taking into account peculiarities of the structure of the emulsion are broadened.

The stability of the carbon emulsions is normally evaluated after alteration of the particle size of the emulsion during storage. This purely chemical colloid approach is inadequate. For emulsions which represent the basis of preparations and are intended to be used for intravenous injections, information about the emulsion stability is not only of great significance in in vitro tests but also the possibility of predicting the emulsion stability when flowing through the bloodstream. This information can be obtained if ideas about the emulsion structure can be fixed clearly. The particles of the emulsions have the shape of a two-layer ball, in the middle of which there is a PFC (particle core) and on the surface of which there is an emulsifier layer (shell) [12]. The shell thickness of the emulsifier is low and is 5-10% of the particle diameter. The behavior of the emulsions in the bloodstream (cooperation with plasma proteins and blood cells, elimination rate etc.) and the stability during long-term storage depend greatly however upon the strength and the state of the surface-active substance around the particles. For this reason, it is necessary to obtain information at the same time about the particle size and the structural change in the media to be examined in the case of those or other effects.

For the theoretical description and analysis of structural change in emulsions as the basis of infusion media, the following ideas should be emphasised [13]:

1) The "total structure" of the emulsions and their change is characterized by the mean particle average and the distribution according to the particle size.

2) The "microstructure" is characterized by the emulsifier state in the shell and the degree of cooperation of the emulsifier with PFCs, the mutual position of the surfactant molecules, their arrangement, packing density, degree of oxidation and the phase state of the structured molecules.

To date, all researchers have restricted themselves to the analysis of a "general structure" which is totally inadequate because the emulsion stability, biocompatibility and in particular the particle surface properties and the absorption capacity of the particles are determined by the microstructure.

The emulsions according to this invention were compared with the prototype and above all examined for parameters which characterize the change in the general structure with different storage times of produced emulsions.

Secondly, the effect of destructive factors on the emulsion was simulated under conditions which allow the microstructure state of the emulsion to be evaluated. Namely a "stress effect" in the form of a dilution with water was used and a specific change in the parameters in comparison to the native emulsion was undertaken. The water dilution of the emulsions disturbs the set equilibrium between the absorption layer of the surfactants (shell) and the surfactant molecules in the dispersion medium. For this reason, it has a specific prognostic meaningfulness with respect to maintaining the stability of the metastable system (fluorocarbon emulsion) or the decomposition thereof.

Furthermore, the change in microstructure and the compatibility of the emulsions during contact with blood serum as system model was examined (examination of the biocompatibility of the emulsion in in vitro tests). The cooperation of two heterogeneous disperse systems, blood serum and fluorocarbon emulsion, characterizes the change in surface particle properties during penetration into the bloodstream and the microstructure change in the emulsion during storage. The change in the general structure and the microstructure was examined at equal periods of time in the course of 12 months.

In order to detect the changes in the mentioned state parameters during storage, methods and approaches were needed which would not have introduced additional disturbances into the system to be examined during measurements. As such, optical testing methods were selected, tested and developed.

In order to evaluate the general structure, a turbidimetric method or turbidity spectrum method [14] was chosen by the inventors. This method was used also for evaluating the particle size distribution in the emulsions to be examined after centrifugation and fractionation. The change in microstructure of the emulsion or of the particle surface properties which were caused by change in the interrelation of the surfactant molecules in the absorption layer around the fluorocarbon compounds were evaluated with an indirect method in order to find the interaction index (K.sub..tau.) of the emulsion to be examined with blood serum relative to the physiological common salt solution: the relative turbidity K.sub..tau.=.tau..sub.1/.tau..sub.2, .tau..sub.1 and .tau..sub.2 meaning the turbidity of the mixtures of serum/emulsion and serum/physiological common salt solution with a corresponding change in the ratio of components of the mixture [15]. In addition, calculated and experimental .tau.-values were compared in order to confirm the natural constancy of emulsified particles: .tau..sub.calculated=.SIGMA.N.sub.i.quadrature..tau..sub.i (.SIGMA.N.sub.i=1), .tau..sub.i and N.sub.i meaning the turbidity or the proportion of the eliminated fraction and .tau..sub.experiment the turbidity of the same emulsion sample before fractionation.

I. Concrete Compositions of the Emulsion According to this Invention are Indicated in the Following.

Composition 1

The emulsion contains 40% by volume of a fluorocarbon phase (C.sub.v) comprising perfluorodecaline and perfluorooctylbromide in the ratio 1:1 with a perfluorinated supplement as mixture of perfluorotripropylamine and its coproducts: cis- and trans-isomers of perfluoro-1-propyl-3,4-dimethylpyrrolidone and perfluoro-1-propyl-4-methylpiperidine in a quantity of 50% of the total content of fluorocarbon compounds, stabilized in the emulsified state with 5% phospholipid dispersion, which contains egg phospholipid and ricinus oil as adjuvant, the concentration of which is 15% of the total content of the egg phospholipid, in the water-salt medium of the following composition: 2 mmol (115 mg/l) sodium chloride, 2 mmol once-substituted potassium dihydrogen phosphate (310 mg water-free salt/l), 7.5 mmol twice-substituted sodium dihydrogen phosphate (460 mg water-free salt/l), 318 mmol mannite (58 g mannitol/l) in injection water. The osmotic pressure was 310 mosmol/l. The mean average diameter of the emulsion particles was 0.195 .mu.m.

Composition 2

The emulsion according to composition 1 was characterized in that it contained 20% by volume of a fluorocarbon phase (C.sub.v) comprising perfluorodecaline and perfluorooctylbromide in the ratio 10:1 with a supplement as mixture of perfluorotripropylamine and its coproducts: cis- and trans-isomers of perfluoro-1-propyl-3,4-dimethylpyrrolidone and perfluoro-1-propyl-4-methylpiperidine, with additional perfluoro-N-methylcyclohexylpiperidine in a quantity of 25% of the total content of the fluorocarbon compounds, stabilized in the emulsified state with 25% phospholipid dispersion, which contains soya phospholipid and soya oil as adjuvant, the concentration of which is 10% of the total content of the egg phospholipid, in the water-salt medium of the following composition: 2 mmol once-substituted, sodium dihydrogen phosphate (276 mg water-free salt/l), 7.5 mmol twice-substituted, sodium dihydrogen phosphate (460 mg water-free salt/l), 278 mmol mannite (50 g mannitol/l) in injection water. The osmotic pressure was 270 mosmol/l. The mean average diameter of the emulsion particles was 0.1 .mu.m.

Composition 3

The emulsion according to composition 1 was characterized in that it contained 15% by volume of a fluorocarbon phase (C.sub.v) comprising perfluorodecaline and perfluorooctylbromide in the ratio 1:10 with a supplement as mixture of perfluorotripropylamine and its coproducts: cis- and trans-isomers of perfluoro-1-propyl-3,4-dimethylpyrrolidone and perfluoro-1-propyl-4-methylpiperidine, with additional perfluoro-N-methylcyclohexylpiperidine in a quantity of 5% of the total content of the fluorocarbon compounds, stabilized in the emulsified state with 2% phospholipid dispersion, which contains soya and egg phospholipid and sunflower seed oil as adjuvant, the concentration of which is 5% of the total content of phospholipids, in the water-salt medium of the following composition: 1 mmol once-substituted, sodium dihydrogen phosphate (138 mg water-free salt/l), 3.7 mmol twice-substituted, sodium dihydrogen phosphate (230 mg water-free salt/l), 100 mmol mannite (18 g mannitol/l) in injection water. The osmotic pressure was 105 mosmol/l. The mean average diameter of the emulsion particles was 0.08 .mu.m.

Composition 4

The emulsion according to composition 1 was characterized in that it contained 10% by volume of a fluorocarbon phase (C.sub.v) comprising perfluorodecaline and perfluorooctylbromide in the ratio 2:1 with a supplement as mixture of perfluorotripropylamine and its coproducts: cis- and trans-isomers of perfluoro-1-propyl-3,4-dimethylpyrrolidone and perfluoro-1-propyl-4-methylpiperidine, with additional perfluoro-N-methylcyclohexylpiperidine in a quantity of 0.2% of the total content of the fluorocarbon compounds, stabilized in the emulsified state with 2% phospholipid dispersion, which contains egg phospholipid and sunflower seed and soya oil as adjuvant, the concentration of which is 2% of the total content of the egg phospholipids, in the water-salt medium of the following composition: 1 mmol once-substituted, sodium dihydrogen phosphate (138 mg water-free salt/l), 3.7 mmol twice-substituted, sodium dihydrogen phosphate (230 mg water-free salt/l), 90 mmol mannite (13 g mannitol/l) in injection water. The osmotic pressure was 100 mosmol/l. The mean average diameter of the emulsion particles was 0.07 .mu.m.

Composition 5

The emulsion according to composition 1 was characterized in that it contained 2% by volume of a fluorocarbon phase (C.sub.v) comprising perfluorodecaline and perfluorooctylbromide in the ratio 1:2 with a supplement as mixture of perfluorotripropylamine and its coproducts: cis- and trans-isomers of perfluoro-1-propyl-3,4-dimethylpyrrolidone and perfluoro-1-propyl-4-methylpiperidine, with additional perfluoro-N-methylcyclohexylpiperidine in a quantity of 10% of the total content of the fluorocarbon compounds, stabilized in the emulsified state with 0.2% phospholipid dispersion, which contains soya phospholipid and soya and ricinus oil as adjuvant, the concentration of which is 5% of the total content of the soya phospholipids, in the water-salt medium of the following composition: 2 mmol sodium chloride (115 mg water-free salt/l), 2 mmol once-substituted sodium dihydrogen phosphate (276 mg water-free salt/l), 7.5 mmol twice-substituted sodium dihydrogen phosphate (460 mg water-free salt/l), 318 mmol mannite (58 g mannitol/l) in injection water. The osmotic pressure was 350 mosmol/l. The mean average diameter of the emulsion particles was 0.06 .mu.m.

Composition 6

The emulsion according to composition 1 was characterized in that it contained 10% by volume of a fluorocarbon phase (C.sub.v) comprising perfluorodecaline and perfluorooctylbromide in the ratio 4:1 with a supplement as mixture of perfluorotripropylamine and its coproducts: cis- and trans-isomers of perfluoro-1-propyl-3,4-dimethylpyrrolidone and perfluoro-1-propyl-4-methylpiperidine, in a quantity of 4% of the total content of the fluorocarbon compounds, stabilized in the emulsified state with 2% phospholipid dispersion, which contains soya phospholipid and sunflower seed, soya and ricinus oil as adjuvant, the concentration of which is 4% of the total content of phospholipid, in the water-salt medium of the following composition: 2 mmol once-substituted, sodium dihydrogen phosphate (276 mg water-free salt/l), 7.5 mmol twice-substituted sodium dihydrogen phosphate (460 mg water-free salt/l), 200 mmol mannite (36 g mannitol/l) in injection water. The osmotic pressure was 225 mosmol/l. The mean average diameter of the emulsion particles was 0.09 .mu.m.
 

Claim 1 of 21 Claims

1. A perfluorocarbon emulsion for medicinal purposes, comprising: a water-salt medium; a phospholipid dispersion in the water-salt medium; and a plurality of perfluorocarbon compounds homogenized with the phospholipid dispersion, the plurality of perfluorocarbon compounds including a composition of perfluorodecaline and perfluorooctylbromide used as a rapidly eliminated component and a perfluorocarbon supplement including a mixture of perfluorinated tertiary amines, wherein the mixture of perfluorinated tertiary amines contains a mixture of perfluorotripropylamine and coproducts thereof, the mixture of perfluorotripropylamine and coproducts thereof comprising cis- und trans-isomers of perfluoro-1-propyl-3,4-dimethylpyrrolidone and perfluoro-1-propyl-4-methylpiperidine.

 

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