JPH0623202B2 - Method for producing chitosan granules - Google Patents
Method for producing chitosan granulesInfo
- Publication number
- JPH0623202B2 JPH0623202B2 JP16208886A JP16208886A JPH0623202B2 JP H0623202 B2 JPH0623202 B2 JP H0623202B2 JP 16208886 A JP16208886 A JP 16208886A JP 16208886 A JP16208886 A JP 16208886A JP H0623202 B2 JPH0623202 B2 JP H0623202B2
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- chitosan
- granules
- acid
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- concentration
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Description
【発明の詳細な説明】 （産業上の利用分野） 本発明はキトサン粒体の製造方法に関し、更に詳しく
は、医療品担体、注射薬材料、クロマトグラフィー用吸
着材、バイオリアクタ担体等として有用な種々の粒経の
高純度キトサン粒体の提供を目的とする。Description: TECHNICAL FIELD The present invention relates to a method for producing chitosan granules, and more specifically, it is useful as a carrier for medical products, an injectable material, an adsorbent for chromatography, a bioreactor carrier, and the like. It is intended to provide high-purity chitosan granules having various particle sizes.
（従来の技術） 従来、キチンを脱アセチル化して得られるキトサンは公
知であり、そのユニークな性質からして各種の吸着材、
医療品担体、医療材料としての研究が行なわれている。(Prior Art) Chitosan obtained by deacetylating chitin has heretofore been known, and due to its unique property, various adsorbents,
Research is being conducted as a carrier for medical products and a medical material.
例えば、各種担体として利用する場合には、キトサンを
粒状化する技術が重要であり、このような粒状化技術と
しては、キトサンが酸の水溶液に可溶であり、且つキト
サンの酸水溶液は、その中にアルカリを添加することに
よって再びキトサンを析出させるキトサンの酸水溶液を
調製し、これをアルカリにより中断して粒状化する技術
が最も多く提案されている。For example, when used as various carriers, a technique of granulating chitosan is important, and as such a granulating technique, chitosan is soluble in an acid aqueous solution, and an acid aqueous solution of chitosan is The most proposed technique is to prepare an acid aqueous solution of chitosan in which chitosan is precipitated again by adding an alkali therein, and discontinue this with an alkali to granulate.
これらの粒状化方法によれば、平均粒経が数ｍｍから数
１００μｍ程度の粒状キトサンが提供される。According to these granulation methods, granular chitosan having an average particle diameter of several mm to several hundreds of μm is provided.
（発明が解決しようとしている問題点） 上記の公知の方法は、いずれも水性媒体中において、キ
トサンの凝固を行うものであり、比較的平均粒経の大な
る粒状キトサンは得られるものの、例えば、数１０μｍ
程度のキトサン粒体を得るのは非常に困難であり、更に
数μｍ程度のキトサン粒体を得ることとはできない。こ
れは、キトサンの粒状化を水性媒体中で行う結果、キト
サン粒子が微小であるとそれらが水性媒体中で凝集を生
じ易いこと、および、このような微小な状態で凝集を生
じることなく乾燥するのは極めて困難なためである。(Problems to be solved by the invention) In any of the above-mentioned known methods, in an aqueous medium, chitosan is coagulated, and although granular chitosan having a relatively large average particle size is obtained, for example, Several tens of μm
It is very difficult to obtain chitosan granules of a certain degree, and it is not possible to obtain chitosan granules of a few μm. This is because, as a result of performing granulation of chitosan in an aqueous medium, if the chitosan particles are minute, they tend to aggregate in the aqueous medium, and dry in such a minute state without causing aggregation. Because it is extremely difficult.
また、従来方法の場合には、水性媒体中における凝固方
法を使用する結果、操作が煩雑で且つ適正条件の設定が
困難であり、安定した品質の粒体を得るのが困難であっ
た。更に、キトサンの粒状化に際しては、キトサンの酸
水溶液からキトサンを析出させるためのアルカリ等の凝
固剤、析出したキトサン粒子を安定に分散させるための
界面活性剤等の懸濁化剤等が必要であるため、これらの
各種補助剤が、得られるキトサン粒体中に混入し、不純
物を含んだキトサン粒体となるという問題がある。この
問題は、キトサン粒体を医療分野で使用しようとする時
には非常に重要であり、従来方法によるキトサン粒体は
殆ど医療分野では利用することができなかった。Further, in the case of the conventional method, as a result of using the coagulation method in an aqueous medium, the operation is complicated and it is difficult to set appropriate conditions, and it is difficult to obtain granules of stable quality. Furthermore, when granulating chitosan, a coagulant such as an alkali for precipitating chitosan from an acid aqueous solution of chitosan, a suspending agent such as a surfactant for stably dispersing the precipitated chitosan particles are required. Therefore, there is a problem that these various auxiliary agents are mixed in the obtained chitosan granules to form chitosan granules containing impurities. This problem is very important when attempting to use chitosan granules in the medical field, and chitosan granules obtained by the conventional method could hardly be used in the medical field.
また、最近では、キトサンが免疫活性効果があること、
また生理活性物の徐放性担体としての利用可能性等が報
告されているが、このような用途においては、キトサン
の平均粒経はμｍオーダーであること、および不純物を
含有しないことが要求されるため、従来技術によるキト
サン粒体は殆ど利用可能性が見い出し得ないものであっ
た。Also, recently, chitosan has an immunoreactive effect,
Further, it has been reported that the physiologically active substance can be used as a sustained-release carrier. However, in such applications, it is required that the average particle size of chitosan be in the μm order and that it does not contain impurities. Therefore, the chitosan granules according to the prior art could hardly find applicability.
従って、その平均粒経が１０μｍ以下のものから任意の
平均粒経の球状のキトサン粒体を提供できる方法が強く
要望されている。Therefore, there is a strong demand for a method capable of providing spherical chitosan particles having an average particle size of 10 μm or less and having an arbitrary average particle size.
（問題点を解決するための手段） 本発明者は上記の如き従来技術の問題点を解決し、上記
の要望に応えるべく鋭意研究の結果、本発明を完成し
た。(Means for Solving Problems) The present inventor has completed the present invention as a result of earnest research to solve the above-mentioned problems of the prior art and meet the above-mentioned demand.
すなわち、本発明は、キトサンの酸水溶液を噴霧乾燥す
ることを特徴とするキトサン粒体の製造方法である。That is, the present invention is a method for producing chitosan granules, which comprises spray-drying an aqueous acid solution of chitosan.
次に本発明を更に詳細に説明する。本発明者は従来から
キトサンの粒状化について鋭意研究のところ、キトサン
を酸の水溶液に適当な濃度で溶解し、従来技術の如く、
凝固浴中に加えて凝固させるのではなく、得られたキト
サン水溶液を種々の条件で加熱空気中に噴霧して乾燥す
る。すなわちスプレードライ方式で乾燥する時は、何ら
の凝固剤や懸濁化剤等を使用することなく、噴霧乾燥条
件に従って種々の平均粒経のキトサン粒体が極めて容易
に得られることを知見したものである。しかも、このよ
うにして得られる種々の平均粒経のキトサン粒体は、そ
の形状が殆ど角のない球状であり、しかも、凝固剤や懸
濁化剤等を使用しないため、得られるキトサン粒体は非
常に高純度であり、吸着材等の一般的用途は勿論、平均
粒経が１０μｍ以下のものは特に医療分野における担体
材料等として非常に適しているものであった。Next, the present invention will be described in more detail. The present inventor has been earnestly researching the granulation of chitosan, and the chitosan was dissolved in an aqueous solution of an acid at an appropriate concentration, as in the prior art.
Instead of being added to the coagulation bath to coagulate, the resulting aqueous chitosan solution is sprayed into heated air under various conditions to dry. That is, it was found that chitosan granules with various average particle diameters can be obtained very easily according to the spray drying conditions without using any coagulant, suspending agent, etc. when drying by the spray drying method. Is. Moreover, the thus-obtained chitosan granules having various average particle diameters are spherical with almost no corners, and since no coagulant, suspending agent, etc. are used, the obtained chitosan granules are obtained. Has a very high degree of purity, and is not only for general applications such as adsorbents, but also for those having an average particle size of 10 μm or less, which is very suitable as a carrier material in the medical field in particular.
以上の如き本発明方法は次の如くして行われ種々の平均
粒経のキトサン粒体が提供される。The method of the present invention as described above is carried out as follows to provide chitosan granules having various average particle diameters.
本発明において使用するキトサンとは、カニやエビの甲
殻類の外皮中に存在するキチンを脱アセチル化して得ら
れるものであり、それ自体としては周知の材料であり、
種々の脱アセチル化度、種々の分子量のものが市場から
入手できるし、また容易に製造し得るものである。本発
明において使用するキトサンは、これらの公知のキトサ
ン中で、酸の水溶液に溶解できるものはいずれの脱アセ
チル化度でもいずれの分子量のものでも使用できる。Chitosan used in the present invention is obtained by deacetylating chitin existing in the crustaceans and shrimp crustacean shells, and is a material known per se.
Those with various degrees of deacetylation and various molecular weights are commercially available and can be easily produced. The chitosan used in the present invention may be any one of these known chitosans that can be dissolved in an aqueous acid solution and have any degree of deacetylation and any molecular weight.
キトサンを溶解するための酸の水溶液は、酢酸や乳酸等
の有機酸および塩酸等の無機酸のいずれの水溶液でもよ
い。The aqueous solution of an acid for dissolving chitosan may be either an aqueous solution of an organic acid such as acetic acid or lactic acid or an inorganic acid such as hydrochloric acid.
酸の水溶液の酸濃度は、溶解するキトサンの濃度にもよ
るが、一般的には０．１〜１０重量％程度の濃度が好ま
しく、またキトサンの濃度はいずれの濃度でもよいが、
１般的には０．０５〜２０重量％、好ましくは０．１〜
１０重量％程度である。濃度が上記範囲未満であると経
済性が劣り、また上記濃度を越えると、キトサン水溶液
の粘度が高くなり、取扱不便となる。このようなキトサ
ンの濃度や噴霧する際の送液速度等を調製することによ
って、サブミクロンのものから１００μｍオーダーの種
々のキトサン粒体を製造することができる。The acid concentration of the aqueous acid solution depends on the concentration of dissolved chitosan, but is generally preferably about 0.1 to 10% by weight, and the concentration of chitosan may be any concentration.
Generally 0.05 to 20% by weight, preferably 0.1 to
It is about 10% by weight. If the concentration is less than the above range, the economy is poor, and if the concentration exceeds the above range, the viscosity of the chitosan aqueous solution becomes high, which is inconvenient to handle. By adjusting the concentration of such chitosan, the liquid-feeding speed at the time of spraying, etc., various chitosan granules of the order of 100 μm can be produced from submicron ones.
上記のキトサンの水溶液はキトサンの溶解によってｐＨ
は７に近くなるが、更に無害な塩基性物質を加えてｐＨ
を更に７に近づけることによって、一層容易にキトサン
粒体を得ることができる。またキトサンが凝固しない程
度にアルコール等の有機溶剤を添加してもよい。更に、
キトサン水溶液中には予め有用な薬剤、例えば、酵素、
生理活性物質等を適当量添加させておくこともできる。The above-mentioned aqueous solution of chitosan has a pH due to the dissolution of chitosan.
Is close to 7, but the pH can be adjusted by adding harmless basic substances.
By further approaching to 7, chitosan granules can be obtained more easily. An organic solvent such as alcohol may be added to the extent that chitosan does not solidify. Furthermore,
A useful drug such as an enzyme in the chitosan aqueous solution is previously prepared.
It is also possible to add an appropriate amount of a physiologically active substance or the like.
本発明で使用する噴霧乾燥方法自体は公知の方法であ
り、いずれの公知の噴霧乾燥装置も有用である。The spray drying method itself used in the present invention is a known method, and any known spray drying apparatus is also useful.
このような噴霧乾燥機中で上記の如きキトサンの酸水溶
液を１００〜１８０℃程度の熱風中に噴霧することによ
り、溶液は微細な液滴のまま水分が蒸発し、本発明のキ
トサン粒体が得られる。このようにして得られた本発明
のキトサン粒体は、角の殆ど無い球状体であり、その平
均粒経は噴霧乾燥条件に従って１０μｍ以下のものから
１００μｍオーダーのものである。得られたキトサン粒
体には若干酸が残っていることもあるので、更に水洗し
たり、中和および水洗して残っている酸を十分に除去し
てもよく、少量の酸が残留しても問題のない用途ではそ
のままでもよい。By spraying the acid aqueous solution of chitosan as described above in hot air of about 100 to 180 ° C. in such a spray dryer, the solution evaporates water as fine droplets, and the chitosan granules of the present invention are obtained. can get. The thus-obtained chitosan granules of the present invention are spherical bodies having almost no corners, and the average particle diameter thereof is from 10 μm or less to 100 μm order according to the spray drying conditions. Since some acid may remain in the obtained chitosan granules, it may be further washed with water or neutralized and washed to remove the remaining acid sufficiently, and a small amount of acid remains. However, it may be left as it is in case of no problem.
また得られたキトサン粒体は、用途によってはポリイソ
シアネート、ポリエポキシ化合物、グルタルアルデヒド
等の架橋剤によって架橋処理を行い。その耐水性等を高
めてもよい。Further, the obtained chitosan granules are subjected to a crosslinking treatment with a crosslinking agent such as polyisocyanate, polyepoxy compound and glutaraldehyde depending on the use. You may raise the water resistance etc.
（作用・結果） 以上の如き本発明方法によれば、従来方法よりはるかに
簡便に粒度分布の狭いキトサン粒体が提供でき、また噴
霧乾燥条件を変化させることによって、従来方法では困
難な平均粒経が１０μｍ以下の微小のものから１００μ
ｍオーダーの粒体が提供できる。従って、本発明方法に
よるキトサン粒体は、従来公知の平均粒経の大きなキト
サン粒子と同様にゲルクロマトグラフィー、イオン交換
クロマトグラフィー等の交換材、透透析材、イオン交換
体、バイオリアクタの担体等として有用であることは勿
論、従来技術において球状の形状が要求される用途にお
いても有用である。更に平均粒経が１０μｍ以下のキト
サン微小粒体の場合には、高純度であることから、従来
では使用できなかった医療分野での用途、例えば、生理
活性物質の担体や静脈注射剤の材料等として有用であ
る。(Operation / Results) According to the method of the present invention as described above, it is possible to provide chitosan granules having a narrow particle size distribution much more easily than the conventional method, and by changing the spray drying conditions, it is difficult to obtain the average particle size. From microscopic diameter of 10μm or less to 100μ
M-order particles can be provided. Therefore, the chitosan granules according to the method of the present invention include gel chromatography, exchange materials such as ion exchange chromatography, permeation dialysis materials, ion exchangers, bioreactor carriers, etc., similar to conventionally known chitosan particles having a large average particle size. Of course, it is also useful in applications where a spherical shape is required in the prior art. Further, in the case of chitosan fine particles having an average particle size of 10 μm or less, since they are of high purity, they can be used in the medical field which could not be used in the past, for example, carriers of physiologically active substances and materials for intravenous injection. Is useful as
次に実施例を挙げて本発明を更に具体的に説明する。な
お、文中、部または％とあるのは特に断りのない限り重
量基準である。Next, the present invention will be described more specifically with reference to examples. In the text, parts or% are based on weight unless otherwise specified.
実施例１ １％の酢酸水溶液中に脱アセチル化度６３％のキトサン
（分子量約２３万）を０．１％の濃度に溶解してキトサ
ンの酸水溶液を調製し、これを入口温度１３０℃、噴霧
空気圧１kgf／cm2および送液量５．５〜６ml／min.で噴
霧乾燥して、本発明のキトサン粒体を得た。このキトサ
ン粒体の１００個を任意に取り出し、顕微鏡下で観察し
たところ殆どが真球状であり、平均粒経は２μｍであっ
た。このキトサン粒体は各種吸着材や静脈注射剤の材料
として有用である。Example 1 Chitosan (molecular weight of about 230,000) having a deacetylation degree of 63% was dissolved in a 1% acetic acid aqueous solution at a concentration of 0.1% to prepare an acid aqueous solution of chitosan, which was introduced at an inlet temperature of 130 ° C. Spray drying was carried out at a spray air pressure of 1 kgf / cm 2 and a liquid feed rate of 5.5 to 6 ml / min to obtain the chitosan granules of the present invention. When 100 particles of this chitosan granule were arbitrarily taken out and observed under a microscope, most of them were spherical and the average particle diameter was 2 μm. This chitosan granule is useful as a material for various adsorbents and intravenous injections.
実施例２〜６ 実施例１におけるキトサン、酸および噴霧乾燥条件を下
記第１表の如く変えたことを除いて、他は実施例と同様
にして本発明のキトサン粒体を得た。これらのキトサン
粒体はいずれも各種吸着材や静脈注射剤の材料として有
用である。Examples 2 to 6 Chitosan granules of the present invention were obtained in the same manner as in Example 1 except that the chitosan, acid and spray drying conditions in Example 1 were changed as shown in Table 1 below. All of these chitosan granules are useful as materials for various adsorbents and intravenous injections.
第 １ 表 実施例２ キトサン；脱アセチル化度９８％ 分子量３万 溶液濃度１０％ 酸； １０％酢酸 噴霧乾燥；入口温度１２０℃ 噴霧空気圧２kgf／cm2 送液速度５〜６ml／min. キトサン微小粒体の平均粒経；１００μｍ 実施例３ キトサン；脱アセチル化度７２％ 分子量５万 溶液濃度５％ 酸； ５％乳酸 噴霧乾燥；入口温度１４０℃ 噴霧空気圧２kgf／cm2 送液速度４〜５ml／min. キトサン微小粒体の平均粒経；６０μｍ 実施例４ キトサン；脱アセチル化度９９％ 分子量２３万 溶液濃度１％ 酸； １％酢酸 噴霧乾燥；入口温度１３０℃ 噴霧空気圧１kgf／cm2 送液速度５〜６ｍ／min. キトサン微小粒体の平均粒経；８μｍ 実施例５ キトサン；脱アセチル化度５０％ 分子量２０万 溶液濃度０．１％ 酸； ０．５％酢酸 噴霧乾燥；入口温度１２０℃ 噴霧空気圧１kgf／cm2 送液速度４〜５ml／min. キトサン微小粒体の平均粒経；２μｍ 実施例６ キトサン；脱アセチル化度８５％ 分子量３万 溶液濃度０．５％ 酸； ０．５％酢酸 噴霧乾燥；入口温度１１０℃ 噴霧空気圧１kgf／cm2 送液速度５〜５ml／min. キトサン微小粒体の平均速度；７μｍTable 1 Example 2 Chitosan; Deacetylation degree 98%, Molecular weight 30,000 Solution concentration 10% Acid; 10% Acetic acid Spray drying; Inlet temperature 120 ° C Spray air pressure 2 kgf / cm 2 Liquid transfer rate 5-6 ml / min. Chitosan minute Average particle size of granules: 100 μm Example 3 Chitosan; Deacetylation degree 72% Molecular weight 50,000 Solution concentration 5% Acid; 5% Lactic acid Spray drying; Inlet temperature 140 ° C. Spray air pressure 2 kgf / cm 2 Delivery speed 4-5 ml / Min. Average particle size of micro particles of chitosan; 60 μm Example 4 chitosan; degree of deacetylation 99%, molecular weight 230,000, solution concentration 1% acid; 1% acetic acid spray drying; inlet temperature 130 ° C., spray air pressure 1 kgf / cm 2 Liquid velocity 5-6 m / min. Average particle size of chitosan fine particles; 8 μm Example 5 Chitosan; Deacetylation degree 50%, Molecular weight 200,000 Solution concentration 0.1% Acid; 0.5% Acetic acid Spray drying; Inlet temperature 120 ° C spray . Pressure 1 kgf / cm 2 feed rate 4-5 ml / min chitosan fine granules average warp; 2 [mu] m Example 6 Chitosan; deacetylation degree of 85% molecular weight 30,000 solution concentration of 0.5% acid; 0.5% Acetic acid spray-drying; inlet temperature 110 ° C, spraying air pressure 1 kgf / cm 2 liquid feeding speed 5-5 ml / min. Average speed of chitosan fine particles; 7 μm
Claims (3)
特徴とするキトサン粒体の製造方法。1. A method for producing chitosan granules, which comprises spray-drying an aqueous acid solution of chitosan.
量％である特許請求の範囲第(1)項に記載のキトサン粒
体の製造方法。2. The method for producing chitosan granules according to claim 1, wherein the concentration of the chitosan aqueous solution is 0.05 to 20% by weight.
るキトサン粒体の平均粒経を制御する特許請求の範囲第
(1)項に記載のキトサン粒体の製造方法。3. The average particle size of the obtained chitosan granules is controlled by controlling the concentration of an aqueous chitosan solution.
The method for producing a chitosan granule according to the item (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16208886A JPH0623202B2 (en) | 1986-07-11 | 1986-07-11 | Method for producing chitosan granules |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16208886A JPH0623202B2 (en) | 1986-07-11 | 1986-07-11 | Method for producing chitosan granules |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6320302A JPS6320302A (en) | 1988-01-28 |
| JPH0623202B2 true JPH0623202B2 (en) | 1994-03-30 |
Family
ID=15747853
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16208886A Expired - Fee Related JPH0623202B2 (en) | 1986-07-11 | 1986-07-11 | Method for producing chitosan granules |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0623202B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DK602489A (en) * | 1988-11-30 | 1990-05-31 | Rhone Poulenc Sante | PREPARATIONS FOR THE COATING OF FOODS FOR DRUGS |
| GB9710699D0 (en) | 1997-05-24 | 1997-07-16 | Danbiosyst Uk | Gastro-retentive controlled release system |
| US6252003B1 (en) | 1998-06-04 | 2001-06-26 | Kao Corporation | Polymer emulsion and process for producing the same |
| ATE275392T1 (en) | 1999-04-12 | 2004-09-15 | Shionogi & Co | METHOD FOR PRODUCING MEDICINAL PRODUCTS OF A BASIC HYDROPHOBIC ACTIVE SUBSTANCE |
| CN102728079A (en) * | 2012-06-21 | 2012-10-17 | 厦门蓝湾科技有限公司 | Drying method of water-soluble low molecular weight chitosan |
-
1986
- 1986-07-11 JP JP16208886A patent/JPH0623202B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6320302A (en) | 1988-01-28 |
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