By Dr. Shruti Bhat
The pellets were evaluated and characterized for various physical measurements:
1. Particle size analysis: Studied using Sieve analysis and microscopy.
2. Yield: the percentage of desired fraction 22/30 mesh fraction of pellets was calculated.
3. Bulk density: the bulk density was measured at 650 strokes / 15 mins.
4. True density: the true density of pellets was determined by volume –displacement method in a pycnometer using n-hexane.
5. Porosity: porosity was calculated as = bulk volume – True volume / Bulk volume
6. % Index hardness –friability (%IHF): pellet hardness was calculated on the basis of the results of the friability test. For this purpose 00 g of pellets (2/30 mesh fraction) were placed in a friabilator and rotated for 10 mins at 250 revolutions. The pellets were then screened to remove the fines. The % index of hardness was calculated as:
% Index of hardness- friability: residue (g) x 100 / Weight of the sample
7. Angle of repose (Φ): The angle of repose was determined by the “fixed height method” ad was calculated using the following formulation:
Tan (Φ) = pile height / pile radius
The results are recorded and Yates method was employed to calculate the significance of parameters and their interaction.
RESULTS AND DISCUSSION of this article has been omitted to maintain confidentiality of experimental work. Interested readers are requested to contact me at 1-514-743-6159 or email firstname.lastname@example.org
- It is possible to prepare beads with desirable sphericity by controlling the critical parameters. Concentration of sugar (binder) drying between 2 spray operations and pan speed are the critical factors determining the pellet properties.
- The results obtained enabled optimum range for process variables to be defined.
- A factorial design allowed the evaluation of main effects and interactions.
- Definition of objectives and preliminaries calculation showed predictable results for the pan.
- Interpretation of results permitted the definition of the limits of the experimental parameters and specifications of values.
- Solving problems with this technique is of real interest for qualification and quantification of parameters wrt effects and interaction.
- Conventional coating pan is more adaptable for use in pelletization as compared to the dish pelletizer. The beads obtained using pan are with a narrow size distribution, low friability index and high flow ability.
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2. Woodruff C.W., Nuessle N.O., “ Effect of processing variable in particles obtained by extrusion- spheronization processing “ J.Pharm. Sci, 61: 787 (1972).
3. Fonner D.E., Banker G.S., Schwarbrick J.” Micromeritics of granular pharmaceutical solid (I)”. J.Pharm. Sci., 55 :181 (1986)