ABSTRACT
Physical, chemical and microbiological stability of total parenteral nutrient (TPN) admixtures was studied as a function of storage time and temperature. Particle size analysis and zeta potential measurements were carried out to evaluate the possible changes in the kinetic stability of the emulsions as a function of storage time and temperature. The concentration changes of the applied additives, those of the ascorbic acid and L-alanyl-L-glutamine, were also determined under different storage conditions. Our results indicate that there were no significant differences in the particle size and zeta potential values of admixtures stored at the three examined temperatures. The best results were obtained in the case of admixtures stored at 30°C temperature. Rapid decomposition of vitamin C was found while the glutamine showed adequate stability as a function of storage time and temperature. According to the results of the physicochemical examinations 10-day storage period of this type of TPN admixtures can be accepted at room temperature. Their storage does not require refrigeration (2-8°C) thus they can be administered without special preheating ensuring better physiological tolerance. Ascorbic acid can be added to the system preceding the administration to the patient because of its rapid decomposition.
Subject(s)
Parenteral Nutrition, Total , Ascorbic Acid/chemistry , Dipeptides/chemistry , Drug Stability , Drug Storage , Humans , Infant , Particle Size , TemperatureABSTRACT
Surface active agents can be classified 60 years ago with the introduction of the HLB system. The characterization of emulgents allowed their common use in the practice. The objective of the review is to summarize the research in the field of surface active agents and HLB-value. The basic principles and relationships related to HLB are detailed such as the predicting and experimental methods for the determination, as well as the achievements of development and applications of surface active agents.
Subject(s)
Emulsifying Agents , Technology, Pharmaceutical , Emulsifying Agents/classification , Mathematical Computing , Surface-Active Agents/classification , Technology, Pharmaceutical/methodsABSTRACT
The objective of the present study was to investigate the effect of the pellet core materials isomalt, sugar, and microcrystalline cellulose on the in vitro drug release kinetics of coated sustained-release pellets as well as to evaluate the influence of different ratios of polymethacrylate copolymers exhibiting different permeability characteristics on the drug release rate. For characterization of the drug release process of pellets, the effect of osmolality was studied using glucose as an osmotically active agent in the dissolution medium. The pellet cores were layered with diclofenac sodium as model drug and coated with different ratios of Eudragit RS30D and Eudragit RL30D (ERS and ERL; 0:1 and 0.5:0.5 and 1:0 ratio) in a fluid bed apparatus. Physical characteristics such as mechanical strength, shape, and size proved that the inert cores were adequate for further processing. The in vitro dissolution tests were performed using a USP Apparatus I (basket method). The results demonstrated that, besides the ratio of the coating polymers (ERS/ERL), the release mechanism was also influenced by the type of starter core used. Sugar- and isomalt-type pellet cores demonstrated similar drug release profiles.
Subject(s)
Diclofenac/chemistry , Excipients/chemistry , Polymers/chemistry , Polymethacrylic Acids/chemistry , Acrylic Resins , Carbohydrates , Cellulose , Disaccharides , Drug Implants , Sugar AlcoholsABSTRACT
The morphological characteristics of pellets are critical parameters, because of their physico-chemical features depend on the size, shape and surface geometric of the particles. To ensure the spherical shape and required particle of pharmaceutical pellets size is a prerequisite. The detailed technology is basic requirement for the successful and cost efficient production of particles of acceptable quality. Since the determination of the particle size is influenced by the particle shape, therefore microscopic examination is always suggested, which together with image analysis is suitable for the assesment of the most typical parameters. The method of the microscopic image analysis is useful not only for particle size measurement, but also for particle shape and texture evaluation, with a high sensitivity. Using the microscopic method particle shape may be defined either qualitatively and quantitatively. Reviewing the related articles and results on the investigation of sugar pellets demonstrate that roundness characterization is strongly influenced by the applied statistical shape parameters.
Subject(s)
Chemistry, Pharmaceutical/methods , Drug Implants/chemistry , Image Processing, Computer-Assisted/methods , Particle Size , Reproducibility of ResultsABSTRACT
The aim of stability testing lies in its possibility of revealing all the effects that may influence the quality, efficacy and safety of a pharmaceutical preparation. The stability of a dosage form means that the release of the active ingredients remains unchanged or within specific limits. The manner of stability testing is regulated by guidelines, which consist of -- besides the regular tests of the active ingredient and the degradation products, the concerning impurities, the water content, the hardness -- the dissolution tests. Most physical changes influence the drug release in vivo, which can -- in vitro -- be followed by dissolution.
Subject(s)
Pharmaceutical Preparations/standards , Water/chemistry , Drug Stability , Safety , SolubilityABSTRACT
The physical stability of 2 types of total nutrient admixtures was studied as a function of storage time and temperature. One of them contained only structured triglycerides and the other exclusively long-chain triglycerides as lipid components. To evaluate the possible changes in the kinetic stability of the emulsions and in the surface characteristics of the droplets during storage, particle size analysis, zeta potential, and dynamic surface tension measurements were performed. To follow any chemical decomposition processes that occurred during storage, the pH of the emulsions was also monitored. The mean droplet size of emulsions prepared with lipids containing exclusively long-chain triglycerides showed a remarkable increase after 4 days of storage, in contrast with that of the mixtures containing structured lipids. A combination of size distribution, zeta potential, and dynamic surface tension measurements proved to be useful for an adequate tracking of the kinetic stability of total nutrient admixtures. Structured triglycerides not only provide advantageous metabolic effects but improve the physical stability of total parenteral nutrition admixtures.
Subject(s)
Complex Mixtures/chemistry , Drug Carriers/chemistry , Drug Stability , Emulsions/chemistry , Fat Emulsions, Intravenous/chemistry , Lipids/chemistry , Parenteral Nutrition/methods , Kinetics , Materials TestingABSTRACT
PURPOSE: The physical stability of two types of total parenteral nutrient (TPN) admixtures was studied as a function of storage time and temperature. One of them contained only structured triglycerides and the other exclusively long-chain triglycerides as lipid components. METHODS: Droplet size of the mixtures was followed by photon correlation spectroscopy for 10 days. Zeta potential and dynamic surface tension measurements were carried out to evaluate the possible changes in the charge and interfacial surface tension of the emulsion droplets during the storage. pH values were monitored in order to follow the possible decomposition processes in the course of storage. RESULTS: Droplet size of emulsions prepared with lipids containing exclusively long-chain triglycerides showed remarkable increase after 4 days of storage in contrast with that of the mixtures containing structured lipids. CONCLUSIONS: The obtained results indicate that besides the advantageous metabolic effects of structured triglycerides, their application is recommended to improve the physical stability of TPN admixtures.
Subject(s)
Fat Emulsions, Intravenous/analysis , Fat Emulsions, Intravenous/chemistry , Triglycerides/analysis , Triglycerides/chemistry , Drug Stability , Nutritional Physiological PhenomenaABSTRACT
Since drug release from the dosage forms has priority to absorption from the gastrointestinal system, physico-chemical characterisation of pharmaceutical systems is essential during the development of an optimal formulation with high efficacy and quality. Interfacial parameters of several pharmaceutical excipients were studied regarding their possible modifying effect on drug release from the dosage form. These inactive ingredients may influence the interfacial phenomena of the drug carrier system, which behaviour determines both the efficacy and the quality of the pharmaceutical preparation In this work authors deal mainly with the two introducing steps of the LADME model influenced by interfacial parameters on them, namely with the liberation of drug from the dosage form and with the characteristics influencing the absorption through biological membranes, respectively. The objective of the present work was to study modifying effects of excipients on drug liberation in connection with their physical and chemical characteristics such as interfacial tension of solid and liquid phases, wetting contact angle of solid phase and--a calculated quantity,--adhesion tension of the solid particles.