Compactibility of ternary mixtures of pharmaceutical powders

Castillo, S.; Villafuerte, Leopoldo

doi:10.1016/0031-6865(95)00039-9

Cited by 14 publications

(5 citation statements)

References 7 publications

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“…However, even the nominally identical pharmaceutical tablets break at different loads (6)(7)(8)(9)(10)(11)(12)(13). In this context, statistical functions such as Weibull distribution (14,15) has been used in pharmaceutical sciences to describe tablet strength (6)(7)(8)(9)(10)(11)(12)(13), pellet strength (16,17), tablet brittleness (18), disintegration time (19), dissolution rate (20)(21)(22), stability (shelf life) (23), and compaction behavior (24). Tablet strength is also closely related to disintegration time (25,26).…”

Section: Introductionmentioning

confidence: 99%

Effect of Porosity on Strength Distribution of Microcrystalline Cellulose

et al. 2015

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Fracture strength of pharmaceutical compacts varies even for nominally identical samples, which directly affects compaction, comminution, and tablet dosage forms. However, the relationships between porosity and mechanical behavior of compacts are not clear. Here, the effects of porosity on fracture strength and fracture statistics of microcrystalline cellulose compacts were investigated through diametral compression tests. Weibull modulus, a key parameter in Weibull statistics, was observed to decrease with increasing porosity from 17 to 56 vol.%, based on eight sets of compacts at different porosity levels, each set containing ∼ 50 samples, a total of 407 tests. Normal distribution fits better to fracture data for porosity less than 20 vol.%, whereas Weibull distribution is a better fit in the limit of highest porosity. Weibull moduli from 840 unique finite element simulations of isotropic porous materials were compared to experimental Weibull moduli from this research and results on various pharmaceutical materials. Deviations from Weibull statistics are observed. The effect of porosity on fracture strength can be described by a recently proposed micromechanics-based formula.

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Section: Introductionmentioning

confidence: 99%

Effect of Porosity on Strength Distribution of Microcrystalline Cellulose

et al. 2015

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“…The points in Figure 7 are experimental and the lines are the calculated regressions with (2) [18–21].

\begin{matrix} T1 \\ \ln (- \ln (1 - \frac{D}{D_{m a x}})) = n * \ln P c + I, \end{matrix}

where D is the hardness or crushing strength of the tablets, D max is the maximum hardness attained by the tablets, Pc is the compaction pressure, n is the slope of the curve, and I is the intercept of the curve.…”

Section: Resultsmentioning

confidence: 99%

Functional Performance of Chitosan/Carbopol 974P NF Matrices in Captopril Tablets

Aguilar-López

Villafuerte-Robles

2016

Journal of Pharmaceutics

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Chitosan and Carbopol have been used to form a complex through an electrostatic interaction between the protonated amine (NH3+) group of chitosan and the carboxylate (COO−) group of Carbopol. In situ polyelectrolyte complexes formations based on the physical mixture of chitosan and sodium alginate were found and could be used as an oral controlled release matrix. The aim of this work is the assessment of a possible interaction between the particles of chitosan and Carbopol 974P NF that could modify their technological performance in captopril tablets. The drug and excipients were evaluated as mixtures of powders and tablets. The mixtures with captopril contained Carbopol 974P NF, chitosan, or a 1 : 1 mixture thereof with polymer proportions of 10%, 20%, and 30%. The evaluated parameters were the powder flow rate, the powder compressibility index, and the compactibility and release behavior of the tablets. The observed technological behavior points out to a greater interaction between the particles of polymers with different charge than between particles of the individual polymers. This produces more coherent matrices restricting more efficiently the drug dissolution, more coherent tablets with higher compactibility, and less flowing powder mixtures. All this, however, requires additional investigation to confirm the current results.

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“…The procedure consisted of placing each tablet diametrically between two flat surfaces and applying pressure until the tablet breaks. The compactibility profile was described with an equation based on the Weibull distribution [14][15][16]:…”

Section: Compactibility Assessmentmentioning

confidence: 99%

Effect of Components and Deposition on Technological Performance of Ibuprofen Tablets

Velasco¹,

Robles²

2018

Int J App Pharm

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Objective: This work evaluated the influence of the technological properties of polyvinylpyrrolidone (PVP), calcium phosphate (CP) and cross-linked sodium carboxymethylcellulose (CC) as well as the deposition of a solid dispersion, through the solvent evaporation method, on the technological parameters that define the properties of ibuprofen tablets. Methods: The powder flow rate through an orifice, bulk volume and tapped volume of powders, tablet hardness, disintegration time and dissolution profile of the tablets were determined on individual components, their physical mixtures, granules obtained by deposition and solvent evaporation, and tablets obtained at different compaction pressures. Results: The very poor flowability of CP and the high compactibility of PVP were transferred to the powder mixtures, which showed poor flowability, and ibuprofen tablets with twice the compactibility. The tablets disintegration was high with a low proportion of CC (0.5%), but decreased linearly by increasing the proportion of the disintegrant up to 10%. At the same time, the dissolution of the drug after 30 min increased from 3% to 80%. The agglomeration of CP through the deposition of an alcoholic solution of the drug and PVP improved the flow properties and tripled the hardness of the tablets. However, the dissolution after 30 min decreased from 80% to 18%. Conclusion: The physical mixture was the best option to improve the dissolution, while the deposition on an adsorbent, of a solid dispersion of drug-PVP, was the best option to improve the compactibility and flow properties.

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Compactibility of ternary mixtures of pharmaceutical powders

Cited by 14 publications

References 7 publications

Effect of Porosity on Strength Distribution of Microcrystalline Cellulose

Effect of Porosity on Strength Distribution of Microcrystalline Cellulose

Functional Performance of Chitosan/Carbopol 974P NF Matrices in Captopril Tablets

Effect of Components and Deposition on Technological Performance of Ibuprofen Tablets

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