Kemerovo, Kemerovo, Russian Federation
Factors causing the urgency of developing technology of capsules based on non-traditional raw materials, which are mainly plant analogues are considered. Carboxymethylcellulose (CMC), starches, agar, hydroxypropyl methylcellulose (HPMC) are those of economic viability due to cheaper raw materials, consumer demand for the encapsulated drugs and biologically active additives (BAA). New different characteristics that satisfy a wide range of consumers, including those who do not use animal products for religious and / or behavioral (vegetarians) reasons are presented. In the course of studies complex characteristics of organoleptic, physical- chemical, optical, buffering, rheological and structural-mechanical properties, chemical reactivity indices of plant analogues of pharmaceutical gelatin, and combinations thereof to produce capsules were determined. The tested plant analogues of pharmaceutical gelatin for capsules exhibit the properties of weak electrolytes. Active amount of titratable groups in plant analogues of pharmaceutical gelatin from agar and HPMC is small, that makes the contribution of these compounds impossible when predicting the properties of the acid-base complex mixtures or solutions. Plant analogues of pharmaceutical gelatin from starches exhibit sufficiently strong buffering properties, the average number of active groups in a 1% starch solution being 1.9 mM, and the solution’s pKa of plant analogues of pharmaceutical gelatin from pectins in the range from 4.3 to 4.9 pH units respectively. Solutions of plant analogues of pharmaceutical gelatin from carrageenans are chemically unstable in the presence of acid in the solution. Acidity tests showed, that among the studied samples of plant analogues of pharmaceutical gelatin from starch all the starch samples proved to have satisfactory characteristics. The complex properties of plant analogues of pharmaceutical gelatin were examined and the possibility of using plant analogues of pharmaceutical gelatin for soft capsules was proved.
Capsules, plant analogues of pharmaceutical gelatin, physical- chemical properties of hydrocolloids, microbiological parameters
INTRODUCTION
Market analysis of encapsulated drugs and biologically active food additives (BAA) suggests close attention of capsule manufacturing companies to seek alternatives to traditionally used gelatin. This trend is based on the laws of development of the global consumer market: economic viability due to cheaper raw materials, consumer demand for the encapsulated drugs and dietary supplements with new and diverse characteristics that meet a wide range of needs, including those who do not use animal products for religious and/or behavioral (vegetarians) motives. All these factors cause the urgency of developing technology of capsules based on non-traditional raw materials, which can act as the composition of the hydrocolloids of plant origin [1].
This project aims to develop technological opera-tions for obtaining of plant analogue of pharmaceutical gelatin and capsules out of it. Selection of materials for the production of pharmacological capsules must be based on the safety requirements for such products, technological requirements for raw materials at the production stage and basic requirements for capsules themselves - effective delivery and release of the drug or biologically active substance in a given location of gastrointestinal tract (stomach, gut). Ideally, the properties of the capsule as a vehicle for medicinal substances should facilitate the minimization of side effects of drugs, and, if necessary, prolong the effect of the drug due to its gradual release. Plant hydrocolloids - carboxymethylcellulose, sodium alginate, hydroxy-propyl methyl cellulose are used as raw materials and components to produce capsules in this project. The complex characteristics of raw materials to be used is a necessary step for the technology development of capsules production out of these components, including:
- organoleptic characteristics, physical-chemical properties and safety performance;
- analysis of the stability of raw materials and components for different operating conditions (temperature, pH, and others);
- characterization of the rheological properties of aqueous solutions of components, as this parameter is crucial for the preparation of capsules with the walls of specified and uniform thickness;
- analysis of the conditions of gelation (pH, tempe-rature, concentration of the gelling agent, and others);
- analysis of gel dry conditions, structure and properties of resulting polymer films.
Natural hydrocolloids are widely used in the pharmaceutical and food industries for stabilizing of cultures, reducing weight loss of the feedstock, improving consistency and for preventing "oedema" products. Currently, carboxymethylcellulose, sodium alginate, gelatin, collagen, and hydroxypropylmethyl-cellulose are widely used [2, 3].
1. Morris, V.J., Gromer, A., Kirby, A.R., et al., Using AFM and force spectroscopy to determine pectin structure and (bio) functionality, Food hydrocolloids, 2011, vol. 25, pp. 230-327.
2. Austarheim, I., Christiensen, B.E., Hegna, I.K., et al., Chemical and biological characterization of pectin-like polysaccharides from the bark of the Malian medicinal tree Cola cordifolia, Carbohydrate polymers, 2012, vol. 89, pp. 259-268.
3. Balysheva, V.I., et al., Immobilization of animal cells in alginate/chitosan microcapsules and their cultivation, XII International workshop on bioencapsulation, Faculty of pharmacy, Vitoria (Spain), 2004, pp. 166-169.
4. Dublier, J.-L., Nayouf, M., Tecante, A., and Loisel, C., Flow and viscoelastic properties of cereal starch/hydrocolloids pastes and gels. In: Starch- structure, properties and new technologies. (V.P. Yuryev, P. Tomasik, H. Ruck (Eds.) New York: Nova Science Publishers Inc., 2004, pp. 315.
5. Warrand, J. Flax et al., (Linum usitatissimum) seed cake: a potential source of high molecular weight arabinoxylans, J. Agric. Food Chem., 2005, no. 9, pp. 1449-1452.
6. Warrand J., et al., Structural investigations of the neutral polysaccharide of Linum usitatissimum L. seeds mucilage, J. Biol. Macromol., 2005, vol. 35, no. (3-4), pp. 121-125.
7. Andreenkov, V.A., et al., Rossijskomu proizvoditelju - mnogofunkcional´nye kompozicii otechestvennogo proizvodstva (Multi-functional compositions to the Russian producer), Vestnik AROMAROS-M, 2004. no.1, pp. 3-6.
8. Tihonov, A.I., et al., Biofarmacija (Biopharmacy), Kharkov: NPhaU Publ. Golden Pages, 2003. 240 p.
9. Severin, E.S., and Nikolaev, A.Ja., Biohimija (Biochemistry), Moscow: GEOTAR-MED Publ., 2005. 488 p.
10. Vojuckij, S.S., Kurs kolloidnoj himii (The course of colloidal chemistry), Moscow: Himija, 1975. 512 p.
