Factors affecting performance and manufacturability of naproxen Liqui-Pellet

Liquisolid systems as a novel approach in formulation and manufacturing of solid dosage forms: Challenges and perspectives

Liquisolid systems are a novel, promising platform for the production of solid dosage forms with a high liquid content, i.e. dispersion of the drug in a suitable, hydrophilic, non-volatile liquid vehicle or liquid drug. This technology requires conventional, but highly porous excipients (carrier and coating material in the appropriate ratio) able to absorb/adsorb liquid medication, resulting in both good flowability and acceptable compression properties. This approach has shown great potential to improve the dissolution rate and bioavailability of poorly soluble drugs, and has been recognized as a good alternative to common, more complex and expensive techniques. A variety of applications of this simple technique have been investigated recently, including the preparation of: modified release tablets, orally disintegrating tablets, solid dosage forms with liquid herbal extracts, etc. This emerging technology has numerous advantages, and the most important are: simplicity, cost-effectiveness, applicability in large scale production and environmental friendliness. However, it is accompanied by certain challenges as well, such as limited applicability in the case of highly dosed drugs. This article aims to give a comprehensive overview of recent progress regarding the potential applications of this technology, as well as to give an insight into the new liquisolid-based techniques intending to further support its commercial applicability.

Crystalline Forms of Trazodone Dihydrates

In this study, treatment of anhydrous trazodone powder with ammonium carbamate in warm water crystallised two new polymorphs or dihydrates of trazodone after 5 h, whose structures were determined by X-ray single crystal diffraction. Each dihydrate contains infinite zigzag hydrogen-bonded chains of water molecules, which are stabilised by the N4 acceptor atom of the piperazine ring and the pendant carbonyl O1 atom of the triazole ring, as well as other water molecules. The strong dipole moment expected for the O1 atom makes it a good hydrogen bond acceptor for stabilising the chains of water molecules. Each molecule of trazodone has a similar conformation in both hydrates, except for the propyl chains, which adopt different conformations: anti-gauche in the β hydrate (triazole N-C-C-C and C-C-C-piperazine N) and anti-anti in the γ hydrate. Both piperazine rings adopt chair conformations, and the exocyclic N-C bonds are in equatorial orientations. The Hirshfeld surfaces and two-dimensional fingerprint plots for the polymorphs were calculated using CrystalExplorer17, which indicated contacts significantly shorter than the sum of the van der Waals radii in the vicinity of the piperazine N4 and triazole O1 atoms corresponding to the strong hydrogen bonds accepted by these atoms.

Liqui-Mass Technology as a Novel Tool to Produce Sustained Release Liqui-Tablet Made from Liqui-Pellets

The Liqui-Mass technology (also known as Liqui-Pellet technology) has shown promising results in terms of enhancing the drug release rate of water insoluble drugs in a simplistic approach. However, there is no current study on sustained-release formulation using the Liqui-Mass technology. In this study, an attempt was made to produce a sustained-release Liqui-Tablet for the first time using a matrix-based approach. The non-volatile co-solvent used in the investigation included Tween 80, Tween 20 and Kolliphor EL. The production of sustained-release propranolol hydrochloride Liqui-Tablet was successful, and data from the saturation solubility test and dissolution test did not show much difference among the mentioned non-volatile co-solvent. The best Liqui-Tablet formulation took 24 h for drug release to reach at around 100%. There seemed to be a synergistic retarding drug release effect when a non-volatile co-solvent and Eudragit RS PO were used together. The increase of Eudragit RS PO concentration increased the retardant effect. Kinetic drug release analysis suggests that the best formulation followed the Higuchi model. The flowability of pre-compressed Liqui-Tablet pellets had no issues and its size distribution was narrow. Liqui-Tablet was generally robust and most formulations passed the friability test. The study revealed that Liqui-Mass technology can be employed to sustain drug release.

Producing High-Dose Liqui-Tablet (Ketoprofen 100 mg) for Enhanced Drug Release Using Novel Liqui-Mass Technology

Purpose

Liqui-Tablet is a dosage form derived from Liqui-Mass technology. It has proven to be a promising approach to improve drug dissolution rate of poorly water-soluble drugs. So far, Liqui-Tablet is feasible for low-dose drugs. In this study, an attempt was made to produce high-dose Liqui-Tablet, whilst maintaining ideal physicochemical properties for ease of manufacturing.

Methods

Liqui-Tablets containing 100 mg of ketoprofen were produced using various liquid vehicles including PEG 200, Span 80, Kolliphor EL, PG, and Tween 85. Investigations that were carried out included saturation solubility test, dissolution test, tomographic study, and typical quality control tests for assessing flowability, particle size distribution, friability, and tablet hardness.

Results

The weight of these Liqui-Tablets was acceptable for swallowing (483.8 mg), and the saturation solubility test showed PEG 200 to be the most suitable liquid vehicle (493 mg/mL). Tests investigating physicochemical properties such as flowability, particle size distribution, friability, and tablet hardness have shown no issue concerning quality control and manufacturability. The drug release test of the best formulation has shown extremely rapid drug release at pH 7.4 (100% after 5 min). At pH 1.2 the drug release was reasonable considering the formulation was yet to be optimized.

Conclusion

Despite the high amount of API and liquid vehicle, it is possible to produce a high-dose dosage form with acceptable size and weight for swallowing using the novel Liqui-Mass technology. This has the potential to diversify the technology by removing the restriction of high dose drug that has been seen in liquisolid technology.

Liqui-Tablet: the Innovative Oral Dosage Form Using the Newly Developed Liqui-Mass Technology

In this study, an attempt was made to produce Liqui-Tablets for the first time. This was carried out through the compaction of naproxen Liqui-Pellets. The incentive to convert the novel Liqui-Pellet into Liqui-Tablet was due to the array of inherent advantages of the popular and preferred tablet dosage form. The study showed that naproxen Liqui-Tablet could be successfully produced and the rapid drug release rate (100% drug release ~ 20 min) could be achieved under pH 1.2, where naproxen is insoluble. It was observed that the different pH of the dissolution medium affected the trend of drug release from formulations with varying amounts of liquid vehicle. The order of the fastest drug-releasing formulations was different depending on the pH used. The presence of Neusilin US2 showed considerable enhancement in the drug release rate as well as improving Liqui-Tablet robustness and hardness. Furthermore, images from X-ray micro-tomography displayed a uniform distribution of components in the Liqui-Tablet. The accelerated stability studies showed acceptable stability in terms of dissolution profile.