JPS6128501A - Production of dextrin/hydroxycarboxylic acid/polynuclear ferric compound complex - Google Patents

Abstract

PURPOSE:To obtain the title parenterally administrable complex useful for the treatment of iron deficiency anemia, by reacting a ferric polynuclear hydroxy compound with dextrin and a hydroxycarboxylic acid (alkali salt) in the presence of an alkali carbonated. CONSTITUTION:The purpose dextrin/hydroxycarboxylic acid/polynulear ferric compound complex is obtained by reacting a ferric polynuclear hydroxy compound with dextrinand a hydroxycarboxylic acid (alkali salt) selected from among citric, gluconic, tartaric, malic and succinic acids at a temperature of 100-130 deg.C in the presence of an alkali carbonate and, preferably, removing free dextrin from the obtained complex. Said ferric polynuclear hydroxy compound can be produced by, for example, a method comprising adding dropwise slowly an excess of an aqueous alkali carbonate slution to. e.g., an aqueous ferric chloride solution under agitation, filtering the formed suspended matter and washing it with distilled water.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an iron complex compound useful for the treatment of iron deficiency anemia, and more particularly to a method for producing a parenterally administrable dextrin-hydroxycarboxylic acid-ferric polynuclear complex.

Treatment for iron deficiency anemia mainly relies on oral administration of iron, but in cases where large doses of iron are required, or when orally administered iron is not absorbed properly, or because of side effects, etc. Parenteral administration of iron is used instead of oral administration in cases where the patient cannot tolerate oral administration of iron, or in cases where iron loss due to chronic persistent bleeding is higher than iron absorption and loss of stored iron is observed.

When iron is administered orally, the rate of absorption from the intestinal tract depends on the free iron concentration, so the therapeutic effect is higher when iron is released.As a result, ferrous iron, which can exist as free iron at high concentrations, is often used. There is.

On the other hand, in the case of parenteral iron preparations, it is known that free iron can put the administered body in an extremely dangerous state depending on the amount, so efforts are being made to manufacture iron formulas with a low proportion of free iron. In addition, parenteral iron preparations have a moderately high molecular weight, Cλ, which is excreted little in the urine, a high iron concentration, easy to obtain an injection solution that is isotonic with body fluids, and a near neutrality. It is required to be stable in solution and to have high storage stability in solution state, and has fundamentally different issues from oral iron preparations, and is incomparable in terms of maintaining product safety and stability. Moderately sophisticated manufacturing technology is required.

Several techniques have disclosed that complexes consisting of ferric salts, mono- or oligosancarides, and hydroxycarboxylic acids are effective in treating iron-deficiency anemia. For example, Japanese Patent Publications No. 40-7296 and No. 40-17782 disclose a method for obtaining iron preparations by reacting ferric salts, hexitol, and 1-3 basic hydroxycarboxylic acids in the presence of a dispersion stabilizer. has been done. However, this method only yields preparations with a relatively low iron content of 15-16% by weight, and also has the drawback of acute toxicity, which is as high as LDs*35/kg when administered intravenously to mice. . In addition, in Japanese Patent Publication No. 46-3196, 1 mole of ferric hydroxide, about 1.5 moles of tsurpinto, and about 0 gluconic acid.
．． 4 mol of dextrin, dextran, hydrogenated dextrin or 0.5 mol of hydrogenated dextran (as glucose) with an average molecular weight of 500 to 1.200 to obtain an iron preparation. It is shown. Even in this method, the iron content of the obtained iron preparation is only 21-26% by weight, and when administered to humans, 10% of the administered iron amount is excreted in the urine, resulting in LI)s in mice. It also has drawbacks that should be improved, such as relatively high toxicity of 380 μ/kg when injected intramuscularly. In addition to the drawbacks mentioned above, these saccharide/hydroxycarboxylic acid/ferric iron complexes have relatively small molecular weights, so there is a risk of damaging blood cells, blood vessels, muscles, etc., and the complex solution is far removed from blood and body fluids. It also has disadvantages as a parenteral iron preparation, such as being stable only at high pH.

In addition, in the dextran/ferric iron complex conventionally used as a parenteral iron preparation, dextran itself is expensive, decomposes extremely slowly in the body, and has a tendency to accumulate. When iron complexes are administered parenterally, they are poorly absorbed into the reticuloendothelial system in the body, accumulate in the blood, act as antigens and produce antibodies, and there are also reports that they are carcinogenic. Parenteral iron preparations have various drawbacks.

On the other hand, in the case of dextrin/ferric iron complexes, the composition dextrin has degrading enzymes in the body, so it does not accumulate as seen in dextran, does not produce harmful immune antibodies, and has a large molecular weight. Dextrin/ferric iron complexes have many advantages, such as not being filtered by the kidneys and being excreted in the urine. However, dextrins have reducing groups and tend to reduce ferric iron to ferrous iron, producing free ferrous ions. Further, the dextrin/ferric iron complex has drawbacks such as insufficient long-term storage stability and insufficient thermal stability in an aqueous solution state.

Therefore, the present inventors attempted to improve the stability of these preparations by using high-molecular-weight dextrins, but the desired effects could not be obtained and only products with low iron content and poor therapeutic effects were obtained. On the other hand, attempts were made to produce a dextrin/ferric iron complex that would enhance the therapeutic effect by increasing the iron content, reduce the influence of the reducing group of dextrin, and be less likely to generate free ferrous ions, but such a complex However, the water holding capacity decreased and only unstable products were obtained.

The present inventors have prepared a dextrin having a suitable molecular weight and at least one hydroxycarboxylic acid selected from citric acid, gluconic acid, tartaric acid, malic acid, and succinic acid or an alkali salt thereof, preferably sodium citrate or citric acid. The present invention has been completed by successfully creating an iron complex that satisfies these requirements by coordinating potassium ferric acid with a reactive polynuclear olated form of ferric iron at a preferable ratio. has an iron content of 35 to 47% by weight, hardly any of the administered iron is excreted in the urine, and contains virtually no free iron, providing a highly stable and safe parenteral iron preparation.

According to the present invention, the ferric iron polynuclear olated product and 2W/V%
No precipitation occurs when the solution is left at 4°C for 7 days, and the average molecular weight determined by the number of reducing ends measured by the Somogyi-Nelson method is 2.500 to 10,000, preferably 3.500 to 6,000. Dextrin (hereinafter simply referred to as dextrin) is 0.75 to 1.6 per mole of iron.
0 mol (glucose residue unit, same hereinafter) and at least one of hydroxycarboxylic M selected from citric acid, gluconic acid, tartaric acid, malic acid, succinic acid (hereinafter simply referred to as hydroxycarboxylic acid) or an alkali salt thereof
seeds, preferably citric acid or its sodium salt or potassium salt, from 0.02 to 0.20 mol per mol of iron;
Preferably in the range of 0.05 to 0.16 mol, and a small amount of alkali carbonate selected from sodium carbonate or potassium carbonate (both of which are mixed with water, and heated to 100° C. to 130° C., preferably in a stirrable container). is 102℃～
By heating and stirring at 120° C. for 1 to 5 hours, a crude dextrin/hydroxycarboxylic acid/ferric polynuclear complex solution is obtained.

The crude dextrin/hydroxycarboxylic acid/ferric polynuclear complex solution obtained by the above method is filtered, and the complex is obtained by adding at least one lower alkyl alcohol selected from methyl alcohol, ethyl alcohol, and isopropyl alcohol. The body is precipitated, centrifuged, and repeated as desired to obtain a purified dextrin/hydroxycarboxylic acid/ferric multinuclear complex.
The complex containing lower alkyl alcohol water is then dried by hot air or reduced pressure, crushed if desired, and stored, thereby preparing a parenteral iron preparation at the time of use.

This purification process consists of unreacted hydroxycarboxylic acid alkali salt,
``It is effective in removing free iron, low iron content complexes, and low-molecular complex parts, and is useful for improving the stability and safety of the complexes of the present invention.

The ferric polynuclear olate used in the present invention is, for example, a suspension formed by slowly adding a certain amount of an aqueous alkali carbonate solution dropwise to an aqueous ferric chloride solution while stirring well at cold or room temperature. Wash with distilled water or pure water.
It is relatively easily prepared by filtration or centrifugation. In the ferric polynuclear product obtained in this way, it is preferable that electrolytes, which interfere with coordination bonds with other components and cause a decrease in iron content, be removed as much as possible. , it is relatively easy if you follow the above method,
Economically more advantageous conditions can be achieved than by ion exchange, dialysis, etc.

Furthermore, the hydroxycarboxylic acid or alkali salt thereof used in the present invention and the amount used have important meanings. That is, by using hydroxycarposis acid or its alkali salt as a component of the complex of the present invention, it imparts a negative charge to the target substance, and its stability in solution is dramatically improved compared to the dextrin/ferric iron complex. do. In particular, 0.02 to 0.20 mole of alkali citric acid per mole of iron,
The most significant improvement in stability in solution is observed when the amount is preferably in the range of 0.05 to 0.16 mol.

In addition, as the amount of alkali hydroxycarboxylic acid reacted increases, the molecular weight of the resulting composite tends to decrease.
Therefore, it also has the meaning of controlling the molecular weight of the complex.

Furthermore, as is clear from the experiments described later, the amount of dextrin in the composite of the present invention greatly affects the stability of the composite in solution, and generally, as the amount of dextrin increases and the powder iron content decreases, the amount of free iron decreases. The result is that stability and safety generally decrease.

On the other hand, it is not preferable to reduce the amount of dextrin to an extremely low level since this will reduce the water retention of the complex and its stability in solution. Therefore, in the present invention, the amount of dextrin is kept to the necessary and minimum amount, and a complex with high iron content is made.
It is characterized by the use of hydroxycarboxylic acid to compensate for the decrease in hydrophilicity of the complex. Therefore, the complex of the present invention preferably contains dextrin in an amount within a range that does not reduce the stability of the complex in solution and has a suitably high molecular weight. A complex satisfying these conditions can be obtained by using 0.75 to 1.6 moles (glucose units) of dextrin per mole.

The dextrin/hydroxycarboxylic acid/ferric polynuclear complex thus obtained is a dark brown, odorless, amorphous powder that is gradually soluble in cold water but easily soluble in hot water, and once dissolved, even when cooled. It becomes a stable solution that does not precipitate. Moreover, this solution is sufficiently stable near neutrality. ethanol·
It is a polymer complex that is almost insoluble in organic solvents such as methanol, acetone, and ether, has a negative charge, and has a number average molecular weight distribution of about 140,000 as measured from osmotic pressure.

The iron composite produced according to the present invention has the following characteristics.

1. Due to its high iron content, it is extremely advantageous in terms of formulation and storage.

2. When administered intravenously, the bone marrow, liver,
It is taken up by endothelial cells such as those in the lungs, and does not exhibit cumulative effects in the blood like ferric dextran.

3. The aqueous solution of this complex is stable near neutrality, so there is no fear of damaging living tissue.

4. Since the components other than the iron component that make up this complex are all metabolizable substances, such as dextran and hydroxycarboxylic acid, there is no accumulation during administration, and no other serious side effects are observed.

5. Since it has extremely high storage and thermal stability in the form of a solution, it is extremely advantageous during preparation sterilization and during storage and distribution stages.

The toxicity and pharmacological effects of the complex obtained by the production method of the present invention were investigated.

When the acute toxicity of the dextrin-citrate-ferric polynuclear complex of the present invention was investigated using 8 male mice per administration group, the LD6° after intravenous administration was approximately 460@Fe/kg.
, 2+ showed 500 mgFe/kg or more when administered subcutaneously. Additionally, six male guinea pigs were given 10 m of the complex.
Sensitize by injecting gFe/kg subcutaneously into the abdomen or subcutaneously in the rear neck three times every other day, and after 3 weeks, induce systemic anaphylaxis.
Antigenicity was examined by ltz-Dale reaction, etc., but all tests were negative.

The dextrin-citric acid-ferric polynuclear complex of the present invention using 59pe containing 250+wg of iron was mixed with 201/V% glucose and injected intravenously to patients with agastric iron deficiency anemia to improve iron I investigated the dynamics. According to the blood iron disappearance curve, the iron half-life was approximately 29 minutes, the red blood cell drinking curve continued to rise until 14 days, and the iron utilization rate was over 70%. Also, 5? by body surface measurement of radioactivity? The distribution of pe in the body is highest in the liver after 24 hours, followed by the bone marrow, and then in the tile, and after 3 to 4 days, the highest value is in the bone marrow, which begins to decrease in the liver, and the number of counts in the heart, which represents the blood concentration. An increase in the number of cells was observed, and it was observed that the cells were being utilized by red blood cells.

In addition, for 55 patients with iron deficiency anemia due to gynecological diseases, 1 to 2 tubes per day (1 tube of 2 ml of the present invention dextrin/citric acid/ferric polynuclear complex 1) 0 to 145 I depending on the symptoms.
I1g (50mg as iron) Sorbitol 80mg.

As a result of intravenously or intramuscularly injecting an appropriate amount of distilled water for injection 2 to 7 times a week, the blood pigment concentration increased by 1.5 g/day.
38 cases with d1 or higher, 1.4 to 1.0 g/dl
There were 12 cases with 1.0 g/d1 or less, and 5 cases with 1.0 g/d1 or less.
Significant improvement in anemia was observed in most cases.

No side effects were observed on the gold side, and no symptoms of acute iron toxicity, allergic symptoms, or liver dysfunction were observed.

The complex obtained by the production method of the present invention is dissolved in distilled water as it is, preferably using a non-reducing isotonizing agent example t Lt
- An injection can be prepared by adding an appropriate amount of at least one of common salt, hexites such as turpinto and mannitol, or polyhydric alcohols such as glycerin and ethylene glycol.

Example 1 185 g of newly manufactured polynuclear olated ferric iron (0.25 mol in terms of iron atoms), 34 g of dextrin with molecular weight s, o o o, 1 7.4 g of sodium citrate dihydrate.
and 2.8 g of anhydrous sodium carbonate were charged into an autoclave together with a small amount of water, stirred well, and then heated for 12 hours while stirring.
The reaction was carried out at 0°C for 2 hours. A crude dextrin/citric acid/ferric polynuclear complex solution with a dark brown color was obtained. 500 ml of water was added to the solution and filtered to remove water-insoluble materials. Water was added to the filtrate to bring the total volume to 1, OOOm+, and then 640 ml of methyl alcohol was added to precipitate the product. After standing for a while, the supernatant was discarded, and the precipitate was centrifuged. 350 ml of water was added to the resulting precipitate, and the mixture was dissolved by heating in a boiling bath. Smeared pulp filtration was performed, and water was added to the filtrate to obtain 6001) 1).

600 ml of ethyl alcohol was added to the solution, and after allowing it to stand for a while, the supernatant was removed and centrifuged to obtain a purified dextrin/citric acid/ferric polynuclear complex containing ethyl alcohol water in the form of a cake. The dried crocodile was dried under reduced pressure over calcium chloride at room temperature, and the dried product was pulverized to obtain a dark brown powdered dextrin/citric acid/ferric polynuclear complex 26.
．． 3g was obtained. Iron content 43.5% by weight, yield (based on iron) 81.4% by weight.

Example 2 Newly produced ferric iron polynuclear olized product 78g (5.6g as iron)
19.5 g of dextrin with a molecular weight of 5.100 2-9 g (0.01 mol) of sodium citrate dihydrate and 1.2 g of anhydrous sodium carbonate were stirred together with a small amount of water in a glass simple autoclave while 1) At 5°C. The reaction was carried out for 3 hours to obtain a concentrated solution of dextrin/citric acid/ferric polynuclear complex. After adding 200+*I of water, it was filtered, and water was added to the filtrate to adjust the total volume to 400 ml. To this was added 285 ml of methyl alcohol to precipitate the complex, which was then centrifuged. After separation, the precipitate was dissolved by heating with 150 ml of precipitate, cooled, and then subjected to precise pulp filtration, and water was added to the filtrate to adjust the total volume to 230 ml.

250 ml of ethyl alcohol was added to this to precipitate the complex, which was then centrifuged. The obtained precipitate was dried over calcium chloride under reduced pressure to obtain 10.4 g of a dextrin/citric acid/ferric polynuclear complex. Iron content: 43.0% by weight
, yield (based on iron) 80.4% by weight.

Example 3 Dextrin, glycolic acid, and ferric iron were prepared in the same manner as in Example 2, using 1.0 g (0.01 mol) of sodium glycolate instead of sodium citrate dihydrate used in Example 2. Multinuclear complex 1). 9g was obtained. Iron content 38.7% by weight, yield (based on iron) 82.1% by weight.

Using 2.2 g (0.01 mol) of sodium gluconate, dextrin, gluconic acid,
10.9 g of ferric polynuclear complex was obtained. Iron content 42. yield (based on iron) 83.9% by weight.

Example 5 Using 2.3 g (0.01 mol) of sodium tartrate dihydrate in place of sodium citrate dihydrate, Example 2
Dextrin-tartaric acid-ferric polynuclear complex 1). Obtained 0g. Iron content 4261% by weight, yield (
(based on iron) 82.1% by weight.

Example 6 Dextrin/malic acid/ferric polynuclear complex 10. 8g was obtained. Iron content 39.3% by weight Yield (based on iron) 75.0% by weight.

The dextrin-citric acid-ferric polynuclear complex obtained in Example 2 and the dextrin-citric acid-ferric polynuclear complex prepared in Example 2 without adding sodium citrate dihydrate and under all other conditions. For ferric polynuclear complexes, iron concentration 25m from each
A thermal stability test was conducted by preparing an aqueous solution of g/ml, filling it into an ampoule, and heating the ampoule to 100°C. 25
Thermal stability was compared and determined based on the appearance and electrophoresis experiments of each sample every time.

As a result of the above test, no abnormality was observed in the appearance of the dextrin/rientic acid/ferric polynuclear complex sample even after 200 hours, and the electrophoretic condition was good. In the sample of the dextrin/ferric polynuclear complex without addition, gelation occurred in 25 hours, and origin residues were also observed in electrophoresis. Similar experiments were conducted with hydroxycarboxylic acid alkali salts that can be used in the present invention other than sodium citrate, and the results showed that although they are slightly inferior to sodium citrate, they have better thermal stability than dextrin/ferric iron complexes. Significant improvement was seen.

Note that the thermal stability test conducted below was conducted under the same conditions as the above method.

Examples 7 to 1) 0.01.0.02.0.10.0 for the iron component, respectively.
．． Sodium citrate 2 with a molar ratio of 15.0.3
Water salt, 146 g of newly manufactured ferric iron polynuclear olate (0.2 mol as iron), and 42 g of dextrin with a molecular weight of 5.600.
The yield, iron content, Thermal stability was investigated. The results are shown in Table 1.

*The complex of Example 1) had unfavorable characteristics such as higher pH 1 osmotic pressure and lower molecular weight than other dextrin/citric acid/ferric polynuclear complexes.

The structure of the complex of the present invention is that dextrin, hydroxycarboxylic acid, and ferric iron can stably branch in water by coordinately bonding hydrophilic dextrin and hydroxycarboxylic acid to hydrophobic ferric polynuclear chains. Although it is presumed to form a multinuclear complex, it is a polymer that contains some free dextrin and has a molecular weight distribution.

Regarding the complex of the present invention, the results of measurement experiments such as its elemental composition, residue composition, infrared absorption spectrum, molecular weight, particle size distribution, electrophoresis, thin layer chromatography, intrinsic viscosity, polarography, gel filtration, etc. are shown below. .

Soil-Tennolium grade bottom (Measurement method) 0-iron content analysis: After decomposing the sample with hydrochloric acid, reduce it with zinc powder to produce ferrous ions, and redox with ceric ammonium sulfate using 0-phenanthroline test solution as an indicator. Measured by titration method.

0 Sodium content analysis: Measured using a flame photometer needle.

(Result) The measurement results shown in Table 2 were obtained by the above method.

Table 2 Examples 0% H% Fe% Na%1 14
．． 42.443.52.1 (Measurement method) 0 Ferric polynuclear complex residue (Felon) i Calculated from the above iron content.

0 dextrin residue (C;'6H1005- and free dextrin"6'1005) i: Each sample was hydrolyzed with hydrochloric acid, and the total dextrin was determined as glucose by the Bertrand method and converted to the amount of dextrin.

The free dextrin content can be determined by coprecipitating the complex part with an excess amount of a positively charged colloid titration reagent methyl glycol chitozan solution, taking advantage of the fact that the complex part of the complex of the present invention has a negative charge. After precipitating the excess methyl glycol chitozan by adding a negatively charged colloidal titration reagent polyvinyl potassium sulfate solution, the free dextrin remaining in the supernatant was hydrolyzed with hydrochloric acid to produce glucose, and Bertrand The amount of dextrin was determined by the method and converted into the amount of dextrin. The difference between the total dextrin content and free dextrin content was defined as the dextrin residue content.

0 Citric acid residue [C61) 507]: After hydrolyzing each sample with 6N hydrochloric acid, it was passed through a column packed with a strongly acidic ion exchange resin (Amberlite IR-120) to remove iron that would interfere with the measurement. The passed liquid was concentrated to dryness, dissolved in ethanol water, and transferred to a conductivity titration cell.
Conductivity titration was performed using an I N, NaOH solution, and the amount of citric acid residue was determined from the amount of O, I N Na0 H required for neutralization.

(Result) The measurement results are shown in Table 3.

Table 3 Residues [compositional formula] Example 1 Ferric polynuclear residue (FeOOH) 69.3% by weight Dextrin residue [C6H1o05] 1Il 13.4% by weight Citric acid residue (C5H507) 12.9% by weight % free dextrin [C6H1oo5] 5 8.0% by weight (
Measurement method) Measurement was carried out by the potassium bromide tablet method using an infrared spectrophotometer needle (model EPI-G3, newly manufactured by Hitachi).

(Results) The infrared absorption spectra of the samples measured were in good agreement with each other, and as a representative example, the infrared absorption spectra and characteristic absorption attributes of the composite of Example 1 are shown in Figure 1 and Table 4. show.

Table 4 Absorption wavenumber Attribution Note 3.4
00c request Associative OH stretching vibration Strong absorption due to dextrin residue, ferric polynuclear olated product residue, weak absorption of citric acid Absorption 1.380cm' derived from citric acid residue Carboxylic acid C-O stretching, citric acid residue Origin 0-1 (Broad and strong absorption caused by bending vibration 1.150 cm Due to stretching vibration of C-0-C Weak absorption of dextrin residue Origin 1, 080 cm Weak absorption caused by dextrin residue due to stretching vibration of secondary OH Absorption Derived from enoic acid residues 1.
020 cm Stretching vibration of primary OH Broad and strong absorption due to dextrin residue 700 cm Absorption due to bending vibration of OR This supports the structure of the complex of the present invention, in which dextrin and citric acid are thought to be coordinately bonded to ferric polynuclear residues.

Jou-Kou Okubonshi I (Measurement method) The relationship between sample concentration (C) and osmotic pressure (π) was determined using a high-speed membrane osmometer for the complex of Example 1, and 1dn-RT
(π/C)C,. From the relational expression, number average molecule/deg m
ol, T = absolute temperature of the measurement system. ) The molecular weight of the portion excluding the present invention as much as possible was determined for reference2.
It was 34×10.

(Result) The above measurement results are summarized in Table 5.

Table 5 Example Team 6 1 1.4X10 (Measurement Method) A 5 w/v% aqueous solution of each complex in Example 1 was filtered through ultrafiltration membranes with various pore sizes, and the iron concentration of the filtrate was determined by o -
It was measured by a colorimetric method using phenanthroline, and the particle size distribution of each sample was determined from the iron component filtration rate.

(Results) The particle size of each sample in the aqueous solution has a distribution of approximately 0.03 to 0.1 μ, of which approximately 90% is 0.05 to 0.08 μ.
The particles had particle sizes in the range of .

1-1 Air bed movement (measurement method) Cellulose acetate membrane <5 x 6 cm) was soaked in each phosphate buffer solution (pH 5, 7, 6, 0, 6, 5, ?, 0.7).
．． 5 and 8.0), remove excess buffer by gently sandwiching it with filter paper, and place it in an electrophoresis cell containing phosphate buffer of the same pH, and add a 5 w/v% sample solution to cellulose. Deposit on the center line of the acetate film and apply a voltage of 90
A current was applied for 40 minutes at V, and the movement of the brown spot on the sample was observed.

(Results) All samples moved to the anode. The migration distances are shown in Table 6.

Table 6 pH of buffer solution 5,76,06,57,0? , 5 8.0
In addition, in this experiment, if free iron ions were present, pale yellow iron phosphate (FePO4
) is thought to be generated and remain at the origin, but no corresponding coarse spots were observed.

Chromatography (measurement method) The composite of Example 1 was spotted on a sintered thin layer plate (5X20c+a) of silica gel/glass powder, and the developing solution (1) n-butanol/acetone/water (4:5:
1), (If) Ethyl acetate/glacial acetic acid/water (3:1:
1), <m>ethanol/water/ammonia water <25:
3:4), and then colored with a potassium ferrocyanide test solution and a mixed solution of potassium dichromate and sulfuric acid to measure Rf.

Since the composite of the present invention is a polymer compound, the spot did not move from the origin. Also, free citric acid or sodium citrate and free glucose were not detected.

Sample solutions of various concentrations were prepared from each sample. The specific gravity of the solution and water was measured at 30 ± 0.1°C using a Schwrengel-Ostwald bichnometer, and
The flow time was measured at 30 ± 0.1°C using an Ubbelohde capillary viscometer, and the polar (ηSp: specific viscosity, C
: sample concentration).

(Result) Table 7 shows the intrinsic viscosity [η] of each sample.

Table 7 Example positive [η] 1 0.049 (Measurement method) Based on the method described in JIS-KOIII, supporting salt solution (
Warhole buffer pH 3, 50, 4, 50, 5, 45)
Transfer 5ml to an electrolysis bottle and add sample solution (60.0mg/m
1, Ca 25mgFe/ml) or ferric ammonium sulfate solution (25ml as ferric ion)
gFe/ml) was added, and the mixture was placed in a constant temperature bath at 25° C. and nitrogen was bubbled through it for about 15 minutes to remove dissolved oxygen, thereby preparing an electrolytic solution. For this electrolyte, a DC polarograph was operated with a mercury column of 60 cm, a current sensitivity of 30 nA/m+s, a damping of 5, and a saturated calomel electrode standard (vsSCE), and the half-wave potential (E!4) and wave height (i) were calculated from the obtained polarogram. It was measured.

(Results) Measured values of half-wave potential and wave height and schematic diagrams of polarograms for the complex and ferric ion of Example 1 are shown in Table 8.
and shown in FIG.

Table 8 Electrolyte 1st wave pH Iron concentration F,, A (V) i (mm)3
．． 50 --0.2128.5 fruit/male side 1
4.50 104.4 -0.30 29.55
．． 45 g/ml -0,3929,0 Ferric 3.50 0.07 29.0
Ion 4.50 25.0. 0.05
'30.05.45 g/ml -0,151
9.5 Second wave E! 4 (V)' i (mm) -1,2957,0 Example 1 -1.31 60.0-1.33
61.5 Ferric iron -1,2958,0 ion -1,3060,0 -1,3139,0 From this experiment, the half-wave potential of the complex of the present invention is the half-wave potential of ferric ion at any pH. It is considered that the complex of the present invention forms a stable complex. The wave height is as small as that of ferric ion when compared per unit iron concentration in the electrolyte, and this is thought to be due to the formation of a complex with a large molecular weight. Furthermore, under these conditions, no wave was observed in the half-wave potential corresponding to the second wave of ferric ions in the polarogram of the sample, and the presence of ferric ions was not observed.

-] Week I of Siri The complex of Example 1 was subjected to gel filtration under the following conditions, and iron and dextrin were quantified in each elution fraction.

(Conditions) Sample attachment amount 6.00mg, Gel Cef 10-z 6B
Column 40 x 2.5cm Buffer 0.05M citrate buffer (p) I 6
．． 0) Fractional amount 5I1) (Results) The measurement results are shown in Figure 3.

Weigh the amount of a sample containing 5 g of iron from the composite of Example 1,
Add 80ml of water, heat in a boiling water bath, and add 1
00ml, and this liquid was converted into a concentrated sample solution (1mgPe/m
l).

10 ml of the concentrated sample solution was accurately weighed and water was added to make 2 ml, and this solution was designated as sample solution I. Concentrated sample□Liquid 10m
Accurately weigh 1, dry dextrin 0.1g0.2g-
Add 0.4g and 0.8g and dissolve.

Then, add water to make 20% of the sample solution.

It was quiet. Total dextrin concentration of each sample solution.

Table 9 shows the iron content in terms of iron and complex.

Table 9 Sample number Example 1 Total dextrin Iron content concentration (mg/Tsukuda 1) (wt%) N[LI 13 44II
H840 1[123,37 TV 33 32 v 53 26 bottles Each sample solution was sealed in an ampoule and incubated in a boiling water bath for 1 hour, 3 hours, 6 hours, 10 hours, 2
After heating for 5 hours and 50 hours, the amount of free iron was measured.

0 The results are shown in Figure 4.

[Brief explanation of drawings]

Figure 1 shows potassium bromide tablet method 1 of the complex of Example 1.
The infrared absorption spectrum is shown. FIG. 2 shows a schematic representation of the polarogram of the complex of Example 1 in Walhole buffer solution at pH 5.45. FIG. 3 shows the gel filtration elution curve of the complex of Example 1. FIG. 4 shows the relationship between the heating time and the amount of free iron for the sample solution prepared from the composite of Example 1. (6891) Patent Attorney Murayama Sabube 2nd illustration & Kogo tR1 Netsuichii

Claims (5)

[Claims] (1) Adding dextrin and at least one hydroxycarboxylic acid selected from citric acid, gluconic acid, tartaric acid, malic acid, and succinic acid or an alkali salt thereof to a ferric polynuclear olated product in the presence of an alkali carbonate for 100 to 1
A method for producing a dextrin/hydroxycarboxylic acid/ferric polynuclear complex comprising reaction at 30°C. (2) Adding dextrin and at least one hydroxycarboxylic acid selected from citric acid, gluconic acid, tartaric acid, malic acid, and succinic acid or an alkali salt thereof to the ferric polynuclear olated product in the presence of an alkali carbonate to give 100 to 1
A method for producing a dextrin/hydroxycarboxylic acid/ferric polynuclear complex, which comprises reacting at 30°C and removing free dextrin from the resulting complex. (3) The amount of the hydroxycarboxylic acid or its alkali salt is in the range of 0.02 to 0.20 mol, preferably 0.05 to 0.16 mol, per 1 mol of iron; or The manufacturing method according to item 2. (4) Dextrin was added to its 2W/V% solution at 4°C.
No precipitation occurs when left for days, and the average molecular weight determined by the number of reducing ends measured by the Somogyi-Nelson method is 2,500 to 10,000, preferably 3,500 to 3,500.
6,000 dextrin. 6,000 dextrin. (5) Dextrin is 0.75 to 1% per mole of iron.
3. The manufacturing method according to claim 1 or 2, wherein the amount is in the range of 60 moles (glucose residue units).