A Contribution to the Manufacture of Diiodoquin TABLETS by Direct Compression

Six direct compression vehicles and their binary blends in ratios of 1:1, 1:3 and 3:1 were investigated to compress diiodoquin directly into tablets. With respect to the mechanical properties of the produced tablets, Avicel, Celutab and 5TAR-x1500 were the suitable single vehicles for the manufacturing. Five vehicles, except STAR-x1500, produced tablets of fairly long disintegration times (120 min), while the other vehicle could not compress diiodoquin. The results shewed that blending of Avicel or Celutab with STAR-x1500 improved the physical standards of the produced tablets. Other than being a powerful disintegrant, STAR-x1500 could recover the disintegrating effect of Avicel. On the other hand, the reduction in disintegration times of the tablets compressed with STAR-/Celutab blends, was due to the incorporation of STAR-x in the formulations.

In such a case of noncompressible drug, a large concentration of a binary blended vehicle was needed to compress tablets of good physical characters. The least concentration needed to compress diiodoquin into tablets was not less than 42.0% w/w.     

Direct Compression of Piracetam

It is demonstrated that piracetam undergoes plastic deformation during compression. Incorporation of magnesium stearate dramatically reduces the mechanical strength of the tablets. This effect is much less pronounced when using glyceryl behenate as a lubricating agent.

Silicon dioxide on the contrary increases to a great extent the tensile strength of piracetam tablets. This advantageous impact remains unaffected by addition of magnesium stearte on condition that the drug is mixed with silicon dioxide prior to the addition of the lubricant.     

Tabletting Properties of Musol; A New Direct Compression Vehicle

A new autocompressible vehicle, Musol, obtained by chemical modification of an edible seed polysaccharide was evaluated for direct compression properties, A Hausner ratio of 1,2 and percent compressibility of 16.7 obtained for Musol indicate that it has very good flow properties. Musol showed superiority over Avicel PH 101, USP Fast-Flo lactose, and Encompress when evaluated in terns of flow rake of powders and moisture sorption by both powders and their slugs, Compacts prepared with Musol were found to disintegrate by erosion and therefore did not perform as well as either alginic acid or Ac-disol in 250 mg Sulphadimidine tablets. However, good drug release was obtained from aspirin tablets containing 5% w/w Musol as a dry binder. The t₅₀, t₉₀ and Dissolution efficiency were as good as the values obtained with 5% w/w Avicel PH 101, A 50/50 blend of Musol and Avicel PH 101 surpassed other blends in performance.     

Compaction Behaviour of Musol, A New Direct Compression Vehicle

The compaction characteristics of Musol, a new autocompressible vehicle derived through chemical modification of mucuna gum was investigated. Avicel PH 101, Zeparox and Encompress were used as reference tablet vehicles. Values of the mean yield stress derived from the analysis of Heckel plots indicate that Musol consolidates principally by plastic deformation, The effect of lubrication and recompression on friability, tensile strength and re-working potential of the tablets prepared with the vehicles were determined. While Avicel PH 101 yielded the strongest tablets, Musol showed the highest re-working potential for lubricated and un-lubricated slugs. On the basis of friability, tensile Values of strength and re-working potential, Musol than the grades of Zeparpx or Encompress performed better used in the study.     

Tabletting Properties of Musol; A New Direct Compression Vehicle

A new autocompressible vehicle, Musol, obtained by chemical modification of an edible seed polysaccharide was evaluated for direct compression properties, A Hausner ratio of 1,2 and percent compressibility of 16.7 obtained for Musol indicate that it has very good flow properties. Musol showed superiority over Avicel PH 101, USP Fast-Flo lactose, and Encompress when evaluated in terns of flow rake of powders and moisture sorption by both powders and their slugs, Compacts prepared with Musol were found to disintegrate by erosion and therefore did not perform as well as either alginic acid or Ac-disol in 250 mg Sulphadimidine tablets. However, good drug release was obtained from aspirin tablets containing 5% w/w Musol as a dry binder. The t₅₀, t₉₀ and Dissolution efficiency were as good as the values obtained with 5% w/w Avicel PH 101, A 50/50 blend of Musol and Avicel PH 101 surpassed other blends in performance.     

Compaction Behaviour of Musol,A New Direct Compression Vehicle

Abstract

The compaction characteristics of Musol, a new autocompressible vehicle derived through chemical modification of mucuna gum was investigated. Avicel PH 101, Zeparox and Encompress were used as reference tablet vehicles. Values of the mean yield stress derived from the analysis of Heckel plots indicate that Musol consolidates principally by plastic deformation, The effect of lubrication and recompression on friability, tensile strength and re-working potential of the tablets prepared with the vehicles were determined. While Avicel PH 101 yielded the strongest tablets, Musol showed the highest re-working potential for lubricated and un-lubricated slugs. On the basis of friability, tensile Values of strength and re-working potential, Musol than the grades of Zeparpx or Encompress performed better used in the study.     

Direct Compression Characteristics of Vitamin A-Acetate

A study of the direct compression characteristics of vitamin A-acetate has been made, using a wide range of compression speeds (24-620 mm/s). Relative powder density, mean yield pressure derived from Heckel analyses and radial tensile strengths were used as the basis of the investigation.

The mean yield pressure appeared to be independent of compression speed in the range 24-60 mm/s, whilst an increase was observed at higher speeds of 150-620 mm/s, attributable to the presence of predominantly fragmentation and plastic deformation mechanisms of consolidation respectively. Changes in tablet radial tensile strength and relative powder bed density (Do) appears to correlate with the hypothesis of a mixed mechanism of consolidation for vitamin A-acetate.     

Comparative Evaluation of A New Direct Compression Excipient, SoludexTM 15

Soludex^TM15, a new corn-based maltodextrin, has been evaluated and compared to nine frequently used commercial excipients for direct compression. The properties of the excipients reported are median size, particle size distribution, bulk density, flow rate, repose angle, moisture content, and hardness and compressibility at several compaction pressures. The influence of concentration of lubricant and mixing time with a lubricant on hardness of Soludex 15 compacts were determined. The effect of 1% magnesium stearate on the hardness of compacts was determined for the ten excipients. Model formulations for direct compression tablets using Soludex 15 are presented, and for a batch of these tablets the weight variation, friability, hardness, disintegration and dissolution are reported. Soludex 15 exhibited excellent flow and compressibility, and model tablets using Soludex 15 as the direct compression diluent met USP specifications and provided a rapid dissolution of the active ingredient.     

Comparative Evaluation of Several Direct Compression Sugars

Three new and two commercially available sugar matrices were comparatively evaluated for several fundamental properties of direct compression powder systems. These properties included: particle size distribution, powder flow (determined by a recording powder flow meter), bulk density and moisture content. The matrices studied were Dipac, Nutab, and California and Hawaiian (C & H) Products A, B, and C. These matrices were formulated in to chewable ascorbic acid, multivitamin, and antacid tablets, and analyzed for: weight uniformity, thickness, diameter, hardness, disintegration, resistance to impact stress, friability, dissolution and effect due to aging.

The data obtained showed that the new products (C & H products) were comparable, and in some cases, even superior to the commercially available ones.     

Experimentally Designed Optimization of Direct Compression Tablets

The work reported here describes the improvement of an industrial production of tablets formed by direct compression. This formulation contained 50% active substance of plant origin as a nonhygroscopic powder. The first step was to evaluate a number of direct compression excipients in preformulation tests and then make up a basic formulation providing tablets with correct characteristics. The second step was the optimization of the initial formulation using a two-level factorial experimental design. This enabled the best formulations to be selected objectively.     

Comparative Evaluation of Several Direct Compression Sugars

Abstract

Three new and two commercially available sugar matrices were comparatively evaluated for several fundamental properties of direct compression powder systems. These properties included: particle size distribution, powder flow (determined by a recording powder flow meter), bulk density and moisture content. The matrices studied were Dipac, Nutab, and California and Hawaiian (C & H) Products A, B, and C. These matrices were formulated in to chewable ascorbic acid, multivitamin, and antacid tablets, and analyzed for: weight uniformity, thickness, diameter, hardness, disintegration, resistance to impact stress, friability, dissolution and effect due to aging.

The data obtained showed that the new products (C & H products) were comparable, and in some cases, even superior to the commercially available ones.     

Comparative Evaluation of Direct Compression Ampicillin Formulations

Direct compression formulations were developed for ampicillin using methyl vinyl ether/maleic anhydride copolymer (I) and vinyl acetate/crotonic acid copolymer (II) as binders. A comparison was made between these formulations and wet granulation method using gelatin as binder regarding the chemical stability of ampicillin as a function of relative humidity (55 to 90%) and temperature (40 to 75°C). Polymer I showed least moisture uptake followed by polymer II and gelatin. The mechanism suggested here involves moisture uptake and dissolution followed by chemical decomposition. The temperature had lesser effect on stability because of low activation energies but an Arrhenius relationship was established for three formulations studied. It was concluded that formulation using polymer I gives the most ideal combination of physiochemical properties for the direct compression of ampicillin in solid dosage forms.     

Experimentally Designed Optimization of Direct Compression Tablets

Abstract

The work reported here describes the improvement of an industrial production of tablets formed by direct compression. This formulation contained 50% active substance of plant origin as a nonhygroscopic powder. The first step was to evaluate a number of direct compression excipients in preformulation tests and then make up a basic formulation providing tablets with correct characteristics. The second step was the optimization of the initial formulation using a two-level factorial experimental design. This enabled the best formulations to be selected objectively.     

A Study of the Compactibility Characteristics of a Direct Compression and A Wet Granulated Formulation of Norfloxacin

Compaction characteristics of norfloxacin tablets manufactured by both wet granulation and direct compression procedures were studied with the aid of an instrumented single punch tablet press interfaced with a digital computer. Under comparable tabletting conditions, the direct compression formulation required less compressional force than the wet granulated formulation to produce tablets of similar breaking strengths, which indicates superior compactibility. The directly compressed tablets were found to disintegrate faster and release their active component more rapidly during the critical early stages of dissolu-tion. Dissolution and disintegration of the directly compressed tablets generally were less affected by changes in breaking strengths than those compressed from granulated systems.     

Aging of Tablets Prepared by Direct Compression of Bases with Different Moisture Content

Abstract

Properties of aged tablets prepared by the wet granulation method were found to be affected by the moisture content of the granules. In this study, the storage-induced changes in hardness, disintegration and drug release were evaluated for tablets made by direct compression of three different bases with different initial moisture content. Tablets with high initial moisture content were found to increase in hardness upon storage. The magnititude of such increase is dependant upon the physical properties of the base and the absolute moisture content. The increase in hardness may increase the disintegration time and decrease drug release. Tablets with low initial moisture content were minimally affected by storage. The gain of moisture by some of these tablets led to enhancement in disintegration and drug release. Among the tablets studied lactose based tablets with different initial moisture content were found to be the most resistant to changes upon storage.     

Comparative Evaluation of Several Direct Compression Sugars II

Abstract

The formulation efficiency of several sucrose based direct compression vehicles has been evaluated. The effect of compression force on various fundamental tablet properties has been investigated.

It has been observed that even chemically similar matrices may show differences in formulation efficiencies if there are subtile changes in the structure of the particles.

A simple method for evaluating acid neutralizing efficiency of antacid tablets, particularly when aging is concern, has been presented.     

Evaluation of Era-Tab as a Direct Compression Excipient

The physical and compressional properties of a modified rice starch, Era-Tab, were evaluated and compared with those of 4 commercially available direct compression excipients, namely, microcrystalline cellulose (Avicel PH-101), partially pregelatinized starch, spray-dried lactose (Super-Tab Lactose), and granular dicalcium phosphate dihydrate (Emcompress). It was found that Era-Tab possessed high flowability and adequate compressibility. The compacted material made with Era-Tab has a higher crushing strength and a lower friability than 3 other direct compression excipients, except microcrystalline cellulose. Tablets containing terfenadine of the same degree of hardness (10 kg) were also prepared using different direct compression excipients. The disintegration time of the tablets made with Era-Tab was approximately 2.5 min. The maximum of the accumulated percentage of terfenadine released from the tablet reached 90%, and 63.2% of it was released within 20 min. Both the powder characteristics and tablet properties show that the modified rice starch, Era-Tab, is a useful product as a direct compression tablet excipient.     

A Contribution to Hologram Imagery

A very simple method for evaluating hologram imagery in a general holographic arrangement with spherical or plane reference and reconstruction waves is proposed. For the hologram imagery approaching aberration-free case the relations providing new possibilities are introduced. The study is not restricted to plane holograms only but one can also study the imaging of objects reconstructed from volume holograms.