sodium-stearyl-fumarate and stearic-acid

As an essential formulation component for large-scale tablet manufacturing, the lubricant preserves tooling by reducing die-wall friction. Unfortunately, lubrication also often results in adverse effects on tablet characteristics, such as prolonged disintegration, slowed dissolution, and reduced mechanical strength. Therefore, the choice of lubricant and its optimal concentration in a tablet formulation is a critical decision in tablet formulation development to attain low die-wall friction while minimizing negative impact on other tablet properties. Three commercially available tablet lubricants, i.e., magnesium stearate, sodium stearyl fumerate, and stearic acid, were systematically investigated in both plastic and brittle matrices to elucidate their effects on reducing die-wall friction, tablet strength, tablet hardness, tablet friability, and tablet disintegration kinetics. Clear understanding of the lubrication efficiency of commonly used lubricants as well as their impact on tablet characteristics would help future tablet formulation efforts.

Topics: Drug Compounding; Fumarates; Hardness; Lubricants; Powders; Stearic Acids; Tablets; Tensile Strength

This study investigates the effects of a variety of coating materials on the flowability and dissolution of dry-coated cohesive ibuprofen powders, with the ultimate aim to use these in oral dosage forms. A mechanofusion approach was employed to apply a 1% (w/w) dry coating onto ibuprofen powder with coating materials including magnesium stearate (MgSt), L-leucine, sodium stearyl fumarate (SSF) and silica-R972. No significant difference in particle size or shape was measured following mechanofusion with any material. Powder flow behaviours characterised by the Freeman FT4 system indicated coatings of MgSt, L-leucine and silica-R972 produced a notable surface modification and substantially improved flow compared to the unprocessed and SSF-mechanofused powders. ToF-SIMS provided a qualitative measure of coating extent, and indicated a near-complete layer on the drug particle surface after dry coating with MgSt or silica-R972. Of particular note, the dissolution rates of all mechanofused powders were enhanced even with a coating of a highly hydrophobic material such as magnesium stearate. This surprising increase in dissolution rate of the mechanofused powders was attributed to the lower cohesion and the reduced agglomeration after mechanical coating.

Topics: Fumarates; Ibuprofen; Leucine; Models, Chemical; Particle Size; Powders; Rheology; Silicon Dioxide; Solubility; Stearic Acids; Surface Properties

The evaluation of lubricity or flowability of pharmaceutical powders is important for consistent production and quality control of drug products. However, there have been only a few studies on quantitative measurements of the properties of lubricated powders.. Magnesium stearate (MgSt) and sodium stearyl fumarate (SSF) were used as lubricants. Lubricated powders were prepared by adding lubricants to spray-dried lactose under different conditions. To evaluate flowability, the vibrating tube method was used. In this method, the vibration amplitude of the tube is increased at a constant rate, and the mass of the powder discharged from the tube is recorded. Flowability profiles, i.e. the relationships between the mass flow rate and vibration acceleration, were obtained experimentally. To characterize static and dynamic friction properties of powders, critical vibration acceleration required to make powder particles flow and the average mass flow rate were determined.. Addition of 0.5% MgSt was sufficient for the reduction of static friction between particles. Blending time of the lubricants had little effect on the average mass flow rate of lubricated powders. On the other hand, addition of SSF resulted in an increase in static friction at the beginning of blending, and after a certain blending time, flowability improved. The combination of MgSt and SSF improved both static and dynamic friction properties irrespective of the blending time.. The vibrating tube method can be used to evaluate the flowability properties of lubricated powders, and the experimental results provide useful information on the production of pharmaceutical solid dosage forms.

Topics: Fumarates; Lubricants; Powders; Stearic Acids; Technology, Pharmaceutical; Vibration

The aim of this study was to evaluate the effect of lubricants on the characteristics of orally disintegrating (OD) tablets manufactured using the phase transition of sugar alcohol. OD tablets were produced by directly compressing a mixture containing lactose-xylitol granules, disintegrant, glidant and lubricant, and subsequent heating. The effect of the type of lubricant on the tablet characteristics was evaluated using magnesium stearate (Mg-St), sodium stearyl fumarate (SSF), and talc as lubricants. The hardness of the tablets increased to ca. 6kp as a result of heating, regardless of the kind of lubricant. The oral disintegration time of the tablets containing Mg-St or SSF increased with an increase in the hardness. In contrast, the oral disintegration time of the tablets containing talc was not changed despite of an increase in hardness. The water absorption rate of the tablets containing talc was much faster than that of the tablets containing other lubricants. The surface free energy measurement showed that the polarity of the tablet components containing talc was remarkably increased by heating. The water absorption rate of the tablets containing talc was also increased by heating. These results indicate that a more hydrophilic surface might be attained by heating the talc. Consequently, talc was demonstrated to be the most desirable lubricant for the preparation of OD tablets based on the principle of the phase transition of sugar alcohol.

Topics: Absorption; Administration, Oral; Chemical Phenomena; Chemistry, Physical; Excipients; Fumarates; Hardness; Lactose; Lubricants; Porosity; Solubility; Stearic Acids; Sugar Alcohols; Surface Properties; Tablets; Talc; Water; Xylitol

The characteristics of various pharmaceutical dosage forms are influenced by surface properties such as the friction behavior. For example, die wall friction is a key issue in developing a solid dosage form. However, the friction properties are not completely understood mainly because of the lack of fundamental measurements. Herein, the friction behavior of pharmaceutical materials was investigated and compared with their adhesion behavior using atomic force microscopy. The sliding speed causes significant variations in the frictional force. Compared with other materials, lubricant materials showed less distinct differences in friction tests than in adhesion tests, indicating the dependence of the lubricant efficiency on the stress state. The three parameters obtained from the modified Amonton's law, i.e., absolute frictional force, friction coefficient and residual force, showed consistent trends. Overall, the friction behavior was not a direct reflection of the adhesion forces. The intrinsic friction behavior of a single pharmaceutical particle can be quantified using atomic force microscopy.

Topics: Acetaminophen; Adhesiveness; Chemistry, Pharmaceutical; Dosage Forms; Drug Compounding; Excipients; Friction; Fumarates; Kinetics; Lactose; Microscopy, Atomic Force; Models, Chemical; Nanotechnology; Stainless Steel; Stearic Acids; Surface Properties; Technology, Pharmaceutical

The paper deals with a study of tensile strength and disintegration time of compacts made from silicified microcrystalline celluloses, Prosolv SMCC 90, and Prosolv HD 90, in dependence on compression force, addition of two types of lubricants, and two active ingredients. The lubricants were magnesium stearate and sodium stearyl fumarate in a concentration of 0.5%, the active ingredients being ascorbic acid and acetylsalicylic acid in a concentration of 50%. Prosolv SMCC 90 proved to be better compatible than Prosolv HD 90; the compacts were of higher strength, which was markedly increased with increasing compression force. Prosolv HD 90 was more sensitive to additions of lubricants, and a greater decrease in strength was recorded due to the influence of sodium stearyl fumarate. The effect of lubricants on the strength of compacts in the presence of active ingredients was not identical. The disintegration time of compacts from Prosolv HD 90 without as well as with lubricants was shorter than from Prosolv SMCC 90 and was increasing with increasing compression force. Disintegration time was increased with added lubricants, and it was markedly shortened by addition of active ingredients. Compacts containing ascorbic acid possessed a shorter disintegration time than those containing acetylsalicylic acid, and it was not markedly influenced by the presence of lubricants.

Topics: Ascorbic Acid; Aspirin; Cellulose; Chemistry, Pharmaceutical; Excipients; Fumarates; Lubrication; Silicon Dioxide; Stearic Acids; Tablets; Technology, Pharmaceutical; Tensile Strength

In this research we study the influence of two lubricants-Magnesium Stearate and Pruv--on the tablets elaboration of Cimetidine, Ranitidine, Famotidine and Pirenzepine by direct compression. The presence of 0.5% of lubricants improved the flow of all the formulations, but especially the Famotidine's formulation. The formulations with Magnesium Stearate had the worst results in tests of friability and tensile strength. All tablets with drugs and Pruv had high data in indentation hardness. The tablets of Cimetidine, Famotidine and Pirenzepine with Magnesium Stearate had less time of disintegration.

Topics: Anti-Ulcer Agents; Drug Compounding; Excipients; Fumarates; Stearates; Stearic Acids; Tablets