• Geomechanics and Engineering
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• v.34 no.3
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• pp.221-231
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• 2023

Biopolymer stabilization is a sustainable alternative to traditional techniques that cause a lesser negative impact on the environment during production and application. The study aims to minimize the biopolymer dosages by sizing the bio-additives to the nanoscale. This study combines the advantages of bio and nanomaterials in geotechnical engineering applications and attempts to investigate the behaviour of a low viscous biopolymer, nano sodium carboxymethyl cellulose (nCMC), to treat organic soil. Soil is treated with 0.25%, 0.50%, 0.75% and 1.00% of nano-bio additive, and its effect on the plastic behaviour, compaction characteristics, strength, hydraulic conductivity (HC) and compressible nature are investigated. The strength increased by 1.68 times after 90 days of curing at a dosage of 0.5% nCMC through the formation of gel threads connecting the soil particles that stiffened the matrix. The viscosity of 1% nCMC increased exponentially, deterring fluid flow through the voids and reduced the HC by 0.85 times after curing for 90 days. Also, beyond the optimum dosage of 0.50%, the nCMC forms a film around the soil particles that inhibits the inter-particle cohesion causing a reduction in strength. Experimental results show that nCMC can effectively substitute conventional additives to stabilize the soil.

• Journal of Pharmaceutical Investigation
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• v.41 no.2
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• pp.67-73
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• 2011

Ion exchange resins can be one of the good carriers for sustained drug release. However, the sustained release may not be enough only with themselves and hence film coating with rate controlling polymers can be applied to have a further effect on the drug release. Due to the environmental and economic issues of organic solvent for the polymer coating, aqueous polymeric systems were selected to develop dosage forms. Among the many aqueous polymeric dispersions for the film coating, EC (ethylcellulose) based polymers such as Aquacoat$^{(R)}$ ECD and Surelease$^{(R)}$ were evaluated.A fluid-bed coating was applied as a processing method. The drug release rate was quite dependent on the coating level so the release rate could be modified easily by changing different levels of the coating. The drug release rate in the Aquacoat$^{(R)}$ coated resin particles was strongly dependent on curing, which is a thermal treatment to make homogeneous films and circumvent drug release changes during storage. After dissolution test using the compressed tablets in which the coated resin particles are contained, inhomogeneous coating and even pores could be observed showing that the mechanical properties of EC were not resistant to granulation and compaction process. However, when tablets were prepared in different batches, the release profiles were almost identical showing the feasibility of the coated resin particle as incorporated into the tablet formulation.

• YAKHAK HOEJI
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• v.57 no.3
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• pp.205-212
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• 2013

Dissolution test has been performed to control drug quality and to predict in vivo drug release profile of solid dosage forms, so there's a drift towards setting dissolution test instead of disintegration test. However, some solid dosage forms in Korea Pharmaceutical Codex (KPC) are not established the dissolution test yet, so these monographs are necessary to set the specification of dissolution test. In this study, we developed the specification and test method of dissolution test for itopride hydrochloride tablets and tiropramide hydrochloride tablets which are not established the dissolution test yet. According to the "Manual for Guideline Application for Validation of Analytical Procedures" and "Guidelines on Specification of Dissolution test for Oral dosage form" of Korean Pharmacopoeia (KP), we validated and established each development method. Based on the preliminary dissolution profile, we set the dissolution condition(paddle apparatus, pH 1.2 media, 50 rpm). For this condition, we performed the main dissolution test to determine the specification (45 min, 85%). Finally, we validated each analytical method by specificity, linearity, accuracy and precision. These developed methods will be included the next supplement of KPC and also contributed to the quality control of medicines.

• The Journal of Pediatrics of Korean Medicine
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• v.21 no.3
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• pp.11-19
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• 2007

Objective Medication is one the most important things in treatment for children, but prescribing traditional herbal medicine for them is very difficult. Therefore, we made 4 new forms of oriental herbal medicine that has a better taste, smell, and color. These new forms also have a texture that make medicine easier to chew. Methods We made up a question of 20 children visiting $\bigcirc\;\bigcirc$ university hospital. Results and Conclusions 1. Children preferred liquid or pill type of herbal medicine. 2. The preference sensory test of the traditional medicine and new form of medicine had not much difference. 3. On the test for preferences, it resulted as they liked the 4th form of new medicine which was with little bit more of sweet and sour taste, and the 3rdformwithnewcolors. 4. They hated traditional herbal medicine of the taste, smell, color, sensation of texture of material.

• Herbal Formula Science
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• v.22 no.2
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• pp.77-85
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• 2014

Objectives : To determine a dose of medicine precisely and conveniently, this study was tried to specify the weight of Bangyakhappyun pills by measuring in terms of grams. Methods : 1. Selected typical prescriptions in order of size and formula written down in Bangyakhappyun. 2. Pulverized each medicine in prescription and weighed one Bangchonbi(方寸匕). 3. Weighed the 10 seeds of Firmiana simplex sized one(梧子大) which were mixed with auxiliary materials such as water, honey, starch paste, etc. 4. The dosages of other type forms were measured based on the weigh of 10 seeds of Firmiana simplex sized one(梧子大). Results : 1. A well-used size of pills is Firmiana simplex sized one(梧子大) 2. Honey and starch paste are typical auxiliary materials for formulating pills. 3. A weigh of starch paste based 10 seeds of Firmiana simplex sized one(梧子大) ranged between 1.09g and 2.55g. 4. A weigh of honey based 10 seeds of Firmiana simplex sized one(梧子大) ranged between 1.18g and 2.77g. Conclusions : A dosage of each prescription can be calculated in terms of grams. 1. In case of Firminia simplex sized one(梧子大) with paste, a daily dose is 5.28g to 17.8g. 2. In case of Firminia simplex sized one(梧子大) with honey, a daily dose is 11.8g to 17.3g. 3. The dosage of pills with toxic herb and mineral medicinal material for baby is the least amount of 0.017g. 4. The dosage of most tonifying medicinals are over 10g. Table 3. shows more details.

• YAKHAK HOEJI
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• v.49 no.2
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• pp.185-191
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• 2005

The absorption of a P-gp substrate, rhodamine 123, from a liposomal dosage form was investigated across Caco-2 cell monolayers, rat intestines and rat intestinal Peyer's patches in Ussing chamber, Rhodamine 123 was incorporated into liposomes according to the standard evaporation method, which led to a production of liposomes with a mean diameter of 71.3 nm. The permeability (Papp of rhodamine 123 from a water solution across the monolayer was $2.45{\times}10^{-6}$ cm/s for $A{\leftrightarrow}B$ (apical to basal) and $14.0{\times}10^{-6}$ cm/s for $B{\leftrightarrow}A$ (basal to apical) directions, consistent with the fact that rhodamine 123 is one of the P-gp substrates. The transport of rhodamine 123 from the liposomal dosage form was much lower for both directions compared to the solution of rhodamine 123. The transport of rhodamine 123 across the rat intestine was also significantly decreased for both directions, I.e., influx and efflux, by the liposomal incorporation of the compound. The transport of rhodamine 123 across the Peyer's patch was substantially reduced by liposomal incorporation. No difference was found in the transport between the Peyer's patch and non-Peyer's patch. These observations suggest that the contribution of transport via Peyer's patches in the uptake of liposomes may be minimal, especially for rapidly absorbed compounds like rhodamine 123. Therefore, the increased absorption of P-gp substrates does not appear to be feasible by incorporating the compounds in liposomes, due to negligible involvement of Peyer's patches in the uptake of particulate dosage forms like liposomes. Liposomes may rather represent a sustained release dosage form of incorporated compounds.

• Journal of Pharmaceutical Investigation
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• v.40 no.1
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• pp.15-21
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• 2010

Sibutramine is an orally administered centrally-acting antiobesity agent and inhibits both noradrenaline(norephinephirine) and serotonin(5-HT) reuptake. These effects are contributed by its active metabolites, M1 and M2. However, as the free base form of sibutramine is an oil form in room temperature, it had the problem of handling and stability. Thus, this drug should be used in the form of acid salt form in the pharmaceutical application. Unfortunately, anhydrous sibutramine hydrochloride is highly hygroscopic and unstable. In order to solve the hygroscopicity of the anhydrous salt form, another sibutramine acid salt form must be developed as a hydrate form. In this study. to overcome these problems, various of sibutramine acid salt forms were prepared with the pharmaceutically available salts such as maleate, esylate, mandelate, camsylate, besylate, salicylate, tartrate, isethionate and malate forms, and their physicochemical properties were investigated. Sibutramine malate was selected for excellent solubility and stability among the listed salt forms above. Its pharmacokinetic parameters were evaluated in rats comparing with sibutramine HCl, resulting in similar parameters. In vitro dissolution study of sibutramine malate-loaded capsule was performed comparison with commercial product ($Reductil^{(R)}$) in pH 1.2, pH 4.0, pH 6.8 and water medium. Our results indicated that there were no significant differences in their dissolution profiles were similar in all tested medium. Thus, sibutramine malate-loaded capsule should be a potential candiate due to its excellent solubility, good stability and biosimilar absorption.

• Journal of Pharmaceutical Investigation
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• v.34 no.6
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• pp.443-452
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• 2004

Habit is the description of the outer appearance of a crystal. If the environment of a growing crystal affects its external shape without changing its internal structure, a different habit results. Crystal habit and the internal structure of a drug can affect bulk and physicochemical properties, which range from flowability to chemical stability. A polymorph is a solid crystalline phase of a given compound resulting from the possibility of at least two different arrangements of the molecules of that compound in the solid state. Chemical stability and solubility changes due to polymorphism can have an impact on a drug's bioavailability and its development program. During crystallization from a solution, crystals separating may consist of a pure component or be a molecular compound. Solvates are molecular complexes that have incorporated the crystallizing solvent molecule in their lattice. When the solvent incorporated in the solvate is water, it is called a hydrate. To distinguish solvates from polymorphs, which are not molecular compounds, the term pseudopolymorph is used. Identification of possible hydrate compounds is important since their aqueous solubilities can be significantly less than their anhydrous forms. Conversion of an anhydrous compound to a hydrate within the dosage form may reduce the dissolution rate and extent of drug absorption. An amorphous solid may be treated as a supercooled liquid in which the arrangement of molecules is random. Amorphous solids lack the three-dimensional long-range order found in crystalline solids. Since amorphous forms are usually of higher thermodynamic energy than corresponding crystalline forms, solubilities as well as dissolution rates are generally greater. A study on crystal form includes characterization of (l)crystal habit, (2)polymorphism, (3)pseudopolymorphism, (4)amorphous solid.

• Archives of Pharmacal Research
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• v.11 no.3
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• pp.185-196
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• 1988

The inflence of hydrophilic vehicles on percutaneous absorption rate of griseofulvin was studied using intact skin of full thickness of hairless rat. The in vitro absorption rates were used as the characteristics for deciding the optimum formula of ointment vehicles. The optimum formula of vehicle compositions for maximum absorption rate was obtained from the polynomial regression equation and the two graphical techniques, contour graph and partial derivative graph. It was composed of sodium lauryl sulfate (1.65 W /W%), white petrolatum (16.5 W /W%), propylene glycol (12.0 W /W%), and stearyl alcohol (19.6W /W%). The experimental value obtained from the optimum formula and the prediction value were 33.99 and 33.87 ${\mu}g/\sqrt{min}$, respectively. From these results, it was believed that optimum formula for semisolid dosage forms could be obtained from the application of the optimization technique used in this study.

• Archives of Pharmacal Research
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• v.15 no.3
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• pp.208-210
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• 1992

Comparative bioavailability of two tablet dosage forms of ofloxacin (either as Hoechst (India) or Ranbaxy preparation ) was investigated. In a randomized cross-over study, eitht healthy human volunteers received single 200 mg dose of film coated ofloxacin in fasting state. The concentration of ofloxacin in the collected saliva and serum samples were measured by high performance liquid chromatography. No significant difference in bioavailability of both preparations was judged from various serum and seliva pharmacokinetic parameters such as peak concentration, time to peak concentration and are under the curves. Intersubject variation was also found to be insignificant.