Abstract
Apart from their desired effect of reducing the ejection force and punch adhesion, lubricants also have considerable influence on the tablet harness, disintegration, and dissolution times due to their inherent hydrophobicity. This study aimed to investigate the influence of the lubricant molecular structure of the aforementioned characteristics. For this prupose, active pharmaceutical ingredients (APIs) with high and low water solubility have been evaluated in combination with 4 different, stearyl-based lubricants. The study showed that the molecular structure of the lubricant had a significant influence on all of the above mentioned table characteristics. A good molecular balanced between between hydrophobic and slightly hydrophilic moieties - as obtained for sodium stearyl fumarate (PRUV) - resulted in the best overall outcome.
Introduction
Lubricants are a very important part of the tablet formulation. During the tableting process, powder particles are forced to rearrange under the increasing compression force. Lubricants influence this rearrangement and bonding process depending on their molecular structure. After compression, the tablet has to be ejected by the lower punch of the tablet press. The lubricant is also important in this step of the process because it inhibits sticking between the tablet and the punch, which can lead to damage and stop the machines. Finally, the lubricant influences the dissolution and disintegration times, and this, the quality attributes of the tablets. Due to their importance in formulation tablets, there are a lot of lubricants on the market. Most of them are characterized by a long fatty acid chain which imparts hydrophobicity to the lubricant. Examples for such commonly used lubricants are magnesium stearate, sodium stearate, stearic acid, and sodium stearyl fumarate. These lubricants were utilized in this study about the influence of lubricants on tableting characteristics.
Apart from their desired effect of reducing the ejection force and punch adhesion, lubricants also have considerable influence on the tablet harness, disintegration, and dissolution times due to their inherent hydrophobicity. This study aimed to investigate the influence of the lubricant molecular structure of the aforementioned characteristics. For this prupose, active pharmaceutical ingredients (APIs) with high and low water solubility have been evaluated in combination with 4 different, stearyl-based lubricants. The study showed that the molecular structure of the lubricant had a significant influence on all of the above mentioned table characteristics. A good molecular balanced between between hydrophobic and slightly hydrophilic moieties - as obtained for sodium stearyl fumarate (PRUV) - resulted in the best overall outcome.
Introduction
Lubricants are a very important part of the tablet formulation. During the tableting process, powder particles are forced to rearrange under the increasing compression force. Lubricants influence this rearrangement and bonding process depending on their molecular structure. After compression, the tablet has to be ejected by the lower punch of the tablet press. The lubricant is also important in this step of the process because it inhibits sticking between the tablet and the punch, which can lead to damage and stop the machines. Finally, the lubricant influences the dissolution and disintegration times, and this, the quality attributes of the tablets. Due to their importance in formulation tablets, there are a lot of lubricants on the market. Most of them are characterized by a long fatty acid chain which imparts hydrophobicity to the lubricant. Examples for such commonly used lubricants are magnesium stearate, sodium stearate, stearic acid, and sodium stearyl fumarate. These lubricants were utilized in this study about the influence of lubricants on tableting characteristics.