Nifedipine di-matrix depot tablets prepared by compression coating for obtaining zero-order release

Design and evaluation of a zero-order controlled release system based on pre-hydrated constant release area prepared by compression coating technology

The main aim of this research work was to develop and evaluate a drug delivery system with compression coating technology to control drug release at a constant rate. The compression coated tablets (CCTs) consist of the hydrophilic matrix core and the hydrophobic waxy coating. The presence of hydrophobic waxy coating could provide sufficient time for hydration of the core to prevent initial burst release. The mechanism research revealed that erosion was the main way of drug release and the releasing area was constant during the entire release process because the core tablet was located in the cup-shaped coating after one side cover was dropped at the lag time. This made the release behavior exhibit zero-order kinetics (R²>0.99). The coating rupture strength and the core swelling force at the lag time influenced erosion rate thus affecting release rate. Different solubility of drugs (propranolol hydrochloride, melatonin, and nifedipine) was selected as model drugs and the properties of the prepared CCTs in terms of formulations and in vitro release were evaluated. The release rate was independent of solubility, medium pH, and osmotic pressure. This zero-order controlled system could be applied to both controlled drug delivery and chrono pharmaceutical drug delivery.

A review of emerging technologies enabling improved solid oral dosage form manufacturing and processing

Tablets are the most widely utilized solid oral dosage forms because of the advantages of self-administration, stability, ease of handling, transportation, and good patient compliance. Over time, extensive advances have been made in tableting technology. This review aims to provide an insight about the advances in tablet excipients, manufacturing, analytical techniques and deployment of Quality by Design (QbD). Various excipients offering novel functionalities such as solubility enhancement, super-disintegration, taste masking and drug release modifications have been developed. Furthermore, co-processed multifunctional ready-to-use excipients, particularly for tablet dosage forms, have benefitted manufacturing with shorter processing times. Advances in granulation methods, including moist, thermal adhesion, steam, melt, freeze, foam, reverse wet and pneumatic dry granulation, have been proposed to improve product and process performance. Furthermore, methods for particle engineering including hot melt extrusion, extrusion-spheronization, injection molding, spray drying / congealing, co-precipitation and nanotechnology-based approaches have been employed to produce robust tablet formulations. A wide range of tableting technologies including rapidly disintegrating, matrix, tablet-in-tablet, tablet-in-capsule, multilayer tablets and multiparticulate systems have been developed to achieve customized formulation performance. In addition to conventional invasive characterization methods, novel techniques based on laser, tomography, fluorescence, spectroscopy and acoustic approaches have been developed to assess the physical-mechanical attributes of tablet formulations in a non- or minimally invasive manner. Conventional UV-Visible spectroscopy method has been improved (e.g. fiber-optic probes and UV imaging-based approaches) to efficiently record the dissolution profile of tablet formulations. Numerous modifications in tableting presses have also been made to aid machine product changeover, cleaning, and enhance efficiency and productivity. Various process analytical technologies have been employed to track the formulation properties and critical process parameters. These advances will contribute to a strategy for robust tablet dosage forms with excellent performance attributes.

Development, optimization and pharmacokinetic evaluation of biphasic extended-release osmotic drug delivery system of trospium chloride for promising application in treatment of overactive bladder

Background

The research was aimed with an approach to formulate biphasic extended-release system of trospium chloride resulting in controlled release of drug up to 24 h with prospects of better control on urinary frequency, efficacy, tolerability, and improved patient compliance. The push–pull osmotic pump (PPOP) bi-layered tablet of trospium chloride (60 mg) was developed with the use of immediate-release polymers in the pull layer (30 mg drug) and polyethylene oxide in the push layer (remaining 30 mg drug). The tablet was formulated by compression after non-aqueous granulation, seal coating, and semipermeable coating. The tablet prepared was laser drilled to create an orifice for drug release.

Results

Comparative in vitro dissolution and in vivo pharmacokinetic analysis of available marketed formulations demonstrated the complete drug release within 16–18 h; hence the developed biphasic extended-release system has its great importance as it provides zero-order release up to 24 h.

Conclusions

The developed biphasic extended-release drug delivery system of trospium chloride provides the drug release for 24 h with effective plasma concentration in comparison with the available marketed formulation. Extended release of drug from the developed formulation provides scope for its promising application in the treatment of overactive bladder (OAB).

Review on Tablet in Tablet techniques

Background

Among all available dosage form, tablet is most widely used because of its stability and patient acceptability. The better aesthetic quality like color, texture, mouth feel, and taste masking depended on film and sugar coatings, so the coating is an important part in the formulation of the tablet. The present work aims to comprehensively review the formulation, characterization, and challenges in the development of Tablet in Tablet dosage form.

Main text

Film and sugar coatings have the number of disadvantages; most important one is the utilization of aqueous or organic solvent that leads to toxicity. To overcome this problem in the year 1896, Noyes firstly introduced the compression coating or Tablet in Tablet technique. In the development of Tablet in Tablet dosage form, substantial attention among researchers and various research reports and patents inputs can be found in the literature. Also, we focused on the recent advancements in techniques like one-step dry-coating (OSDrC®) for manufacturing Tablet in Tablet dosage form.

Conclusion

The current review gathered information on the latest patent, formulation, advantages, and disadvantages of Tablet in Tablet or compression coating. The review also elaborates on the importance of Tablet in Tablet techniques in the development of a modified release system.

Graphical abstract