Lubricants magnesium stearate

A formulation containing an anti-inflammatory agent (diclofenac sodium), two inert matrices (ethylcellulose and polyvinyl chloride), a lubricant (magnesium stearate) and talc was optimized and prepared by a double compression process. 

As discussed earlier, lubrication of direct compression formulations is one of the more complex and difficult problems faced by a pharmaceutical scientist. The ideal lubrication operation provides the mildest mixing conditions that guarantee sufficient homogeneity of the lubricant. Magnesium stearate, provided as a finely divided powder, is one of the most widely used lubricants in the pharmaceutical industry. Many formulations are sensitive to the lubrication process when the formulation uses magnesium stearate powder. 

Lubricants Magnesium stearate, stearic acid, polyethylene glycol, sodium chloride... 

Figure 14-7 shows tablet data obtained by the students with their materials. It shows the strength of tablets against the compaction force used. We see that the strength of tablets of the inulin powder used here hardly depends on whether lubricant (magnesium stearate) is added or not. This is a desirable characteristic of such powders. 

Milling can affect the adsorption of actives on the carrier surface by altering the surface properties of excipients. It was noticed that milled actives frequently failed blend uniformity criteria, but unmilled active batches consistently met the blend uniformity criteria. By adding lubricant magnesium stearate, the blending content uniformity of the milled batches can be significantly improved. A small amount of amorphous materials could affect the blending characteristics of a direct compression formulation. ... 

Fig. 17 Lubricants. Magnesium stearate (A), calcium arachinate (B), and talc (C).

Lubricants. Among lubricants, magnesium stearate is the most widely used one. It appears in different crystal... 

Differential scanning calorimetry experiments with some directly compressible tablet excipients suggests that aspartame is incompatible with dibasic calcium phosphate and also with the lubricant magnesium stearate. Reactions between aspartame and sugar alcohols are also known. 

Lubricant magnesium stearate 0.7% w/w for Pearlitol 400DC and Pearlitol 500DC magnesium stearate 1% w/w for Pearlitol 300DC. 

The earliest reported pharmaceutical applications of roller compaction were published in 1966 (12). A typical formulation for roller compaction wilt contain a fragmenting material (e.g., lactose), a plastically deforming material such as MCC or com starch, binder (e.g., hydroxyIpropylmethylce Iulose. HPMC). actives, and lubricants (magnesium stearate). 

Boundary Lubricants Magnesium stearate 0.2-2.0 Hydrophobic, variable properties between suppliers. 

We consider the previous example of compatibility testing with the modification that only 2 lubricants, magnesium stearate and glyceryl behenate are to be tested. One of the levels of this variable X, in table 2.14, must be eliminated. 

The main details of the formulation and the limits of the experimental domain were given in table 10.8. Other components not noted in the table were the drug substance (1 - 2%) and a lubricant (magnesium stearate). Tablets at 6 mg were made by direct compression of the mixture. The concentration of drug substance (a soluble salt) were allowed to vary between 1% and 2%. Thus, the domain shown in figure 10.7 may be considered as being repeated for each concentration of drug substance tested. 

Magnesium stearate, talc, Compritol and sodium lauryl sulfate are some of the commonly used lubricants. Magnesium stearate and talc are water insoluble and water repellent. Their hydrophobic nature can lower the contact between the dosage form and GI fluids and thereby cause a slower dissolution. 

Researchers also studied the effect of lubricants on dissolution rate of the active ingredient, which indicated that the more commonly used hydrophobic lubricants (magnesium stearate, aliuninum stearate, calcium stearate, glyceiyl monostearate, stearic acid) could decrease the effective drug-solvent interfacial area and thereby decrease the rate of dissolution of the drug, while water-soluble lubricants (sodiiun oleate, sodium lauryl sulfate, polyethylene glycol 4000 and talc) did not effect the dissolution rate [14, 15]. 

In most situations, reported results focus on the monitoring of the active ingredient alone, as it is often the only parameter that is being measured by wet chemistry. The predichon of the distribution of lubricant (magnesium stearate) was found to be possible at levels as low as 0.5% w/w [31]. Recognizing the importance of excipient homogeneity for the performance of the delivery form, Shi et al. [26] introduced pooled statistics to consider the distribution of not only the active ingredient, but also the excipients. 

Powdered sugar and dextrose are aromatized, granulated with the addition of binding agents (fat, gelatine, gum arabic, tragacanth gum, starch) and lubricants (magnesium stearate), and tabletted under pressure. 

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