Preparation and evaluation of orally disintegrating tablets containing taste-masked microcapsules of berberine hydrochloride

Development of taste masking microcapsules containing azithromycin by fluid bed coating for powder for suspension and in vivo evaluation

This research aims to develop bitter taste masking microcapsules containing azithromycin by a simpler and familiar method, fluid-bed coating technology, in comparison with Zithromax®. Cores of microcapsules, azithromycin microparticles, were prepared by fluid-bed granulation, then taste-masking polymer was covered on by fluid-bed coating technique. Eudragit L100, Eudragit RL100, ethyl cellulose in single and combined with Eudragit L100, Eudragit E100 were used as taste-masking polymers. The obtained microcapsules were characterized by taste masking ability, in-vitro release, SEM, coating thickness and coating efficiency. Combination of ethyl cellulose and Eudragit E100 (3:1) in coating thickness of 45.13 ± 2.12% w/w prevent azithromycin release from microcapsules below bitter taste threshold (1.78 ± 1.17 μg/ml). Bioavailability of powders containing azithromycin microcapsules and pH modulators (50mg Na₃PO₄ and 35mg Mg(OH)₂) was not significantly different from the reference product (Zithromax®, Pfizer) in the rabbit model (p > 0.05). These results support the possibility of developing a generic product containing azithromycin.

Study on the taste-masking effect and mechanism of Acesulfame K on berberine hydrochloride

OBJECTIVE

In our previous taste-masking study, we found that Acesulfame K (AK) had a better taste-masking effect than other high-efficiency sweeteners for several representative bitter natural drugs in aqueous decoction. Furthermore, we performed a preliminary taste-masking study of AK for representative bitter API Berberine Hydrochloride (BH) and found that it had a good taste-masking effect. We also found that flocculent precipitation was generated in the BH solution, but it was not clear whether it was related to the good taste-masking effect. This study was conducted to explore the taste-masking effect and mechanism of AK on BH.

METHODS

The taste-masking effect of AK on BH was evaluated based on the Traditional Human Taste Panel Method and the electronic tongue evaluation method. DSC, XRD, and molecular simulation techniques were used to explore the mechanism of AK on BH, from the macro level and molecular level, respectively.

RESULTS

When evaluating the taste-masking effect, we found that 0.1% AK had the best taste-masking effect on BH, while higher concentrations had a worse taste-masking effect. DSC and XRD revealed that the flocculent precipitation was a complex AK-BH. Finally, by simulating the binding of AK, BH, and TAS2R46 receptors, we found the unique taste-masking mechanism of AK.

CONCLUSION

The sweet taste stimulus of AK can mask the bitter taste stimulus of BH, and AK can generate AK-BH with BH to reduce the contact between BH and bitter taste receptors. Additionally, it could block the expression of the TAS2R46 receptors.

The preparation and characterisation of tasteless core-shell clarithromycin microcapsules

This study aims to fabricate core-shell clarithromycin (CAM) microcapsules to cover up the bitter taste of CAM by spray drying with aqueous polymer dispersion. Water dispersion of Eudragit EPO and Surelease^® were innovatively used to encapsulate CAM into microcapsules via a one-step spray-drying method. The inlet air temperature, airflow rate, CAM-polymer ratio, and particle size of CAM were optimised based on drug content and T_6% (the time taken for the drug to release equal to 6% w/w). The powder properties were assessed by measuring particle size and microstructure using SEM, FT-IR, and PXRD. Furthermore, selected batch was assessed for their drug content, encapsulation efficiency, in vitro release, bitterness, and stability studies. EPO-Surelease^® (1: 4) microcapsules had an average diameter (D50) of 37.69 ± 3.61 μm with a span of 2.395. The drug contents and encapsulation efficiency of EPO-Surelease^®(1:4) were 10.89% and 63.7%, respectively. EPO-Surelease^® (1:4) microcapsules prepared by spray drying with aqueous polymer dispersion can effectively mask the bitter taste of CAM.

Research on Technology of Medicinal Functional Food

Particle coating is one of the oldest pharmaceutical processes that is still in existence. It is the process of applying a thin polymer-based film to a particle or granule containing the active pharmaceutical ingredient. The widely used methods for particle coating are sugar coating, film coating, and enteric coating and the techniques are pan coating, fluidized bed coating, and compression coating. Sugar coating was the earlier coating method, and it was gradually replaced by film coating because it required skilled manipulation. With the technology developing, enteric coating draws more attention. Pan coating is the most classic coating technique, which is applied to sugar coating, film coating and enteric coating. Fluid bed coating is used for a mixture of multiple materials and medicines and keeps the bioavailability high. Compression coating can avoid the harmful effects of moisture and high temperature, while it requires highly accurate machinery.

Influence of Technological Factors on the Quality of Chitosan Microcapsules with Boswellia serata L. Essential Oil

Essential oils contain many volatile compounds that are not stable and lose their pharmacological effect when exposed to the environment. The aim of this study is to protect Boswellia serrata L. essential oil from environmental factors by encapsulation and determine the influence of chitosan concentration and types (2%, 4%; medium and high molecular weights), essential oil concentration, different emulsifiers (Tween and Span), and technological factors (stirring time, launch height, drip rate) on the physical parameters, morphology, texture, and other parameters of the generated gels, emulsions, and microcapsules. For the first time, Boswellia serrata L. essential oil microcapsules with chitosan were prepared by coacervation. Hardness, consistency, stickiness, viscosity, and pH of chitosan gels were tested. Freshly obtained microcapsules were examined for moisture, hardness, resistance to compression, size, and morphology. Results show that different molecular weights and concentrations of chitosan affected gel hardness, consistency, stickiness, viscosity, mobility, and adhesion. An increase in chitosan concentration from 2% to 4% significantly changed the appearance of the microcapsules. It was found that spherical microcapsules were formed when using MMW and HMW 80/1000 chitosan. Chitosan molecular weight, concentration, essential oil concentration, and stirring time all had an impact on the hardness of the microcapsules and their resistance to compression.

Orally Disintegrating Tablet Manufacture via Direct Powder Compression Using Cellulose Nanofiber as a Functional Additive

In recent years, orally disintegrating (OD) tablets have been continuously improved to increase efficacy. Herein, we focused on the benefits of cellulose nanofiber (CNF), a highly functional material, in OD tablet manufacturing. We studied its effects on the physical properties of tablets during manufacture. The analyzed tablet formulations included different content CNF (0-50%; 6 preparations), lactose hydrate, acetaminophen, and magnesium stearate (Mg-St). We measured the angles of repose and evaluated the flowability of the powder. Tablets were prepared on a tabletop and rotary tableting presses, whereafter their weight, drug content, hardness, friability, and disintegration time were evaluated. Although CNF addition slightly reduced powder flowability, continuous tableting was feasible via direct powder compression. Tablet hardness (~40 N) was comparable between CNF-containing (20%) tablets and those prepared with crystalline cellulose under 10 kN compression force. Disintegration time (~30 s) was similar between CNF-supplemented tablets and those supplemented with low-substituted hydroxypropyl cellulose, crospovidone, or croscarmellose sodium. At higher CNF fractions, tablet hardness increased, while friability decreased. Adding ≥30% CNF prolonged the tablet disintegration time. To set the optimized manufacturing condition for ensuring the desired tablet physical properties, we created contour plots for evaluating the effects of CNF concentration and compression force on hardness and disintegration time. A CNF concentration of 10-20% and a compression force of 12-13 kN would allow for the preparation of tablets with a hardness ≥30 N and a disintegration time ≤60 s. Altogether, addition of CNF to the OD tablet formulation for direct powder compression enhanced hardness and disintegration.

3D printing and enteric coating of a hollow capsular device with controlled drug release characteristics prepared using extruded Eudragit® filaments

This work focuses on the extrusion of a brittle, tacky, cationic copolymer i.e. Eudragit® E-100 to prepare filament and subsequent 3D printing of hollow capsular device using the extruded filament. An optimum amount of talc and triethyl citrate was used for the possible extrusion of the polymer. There was no thermal and chemical degradation of the polymer observed after extrusion confirmed by DSC and FTIR analysis. Microscopic analysis of the printed capsule showed the layer-by-layer manner of 3D printing. Capsule parts were printed according to the set dimensions (00 size) with minimal deviation. Printed capsule showed the soluble behaviour in gastric fluid pH 1.2 where within 15 min the encapsulated drug encounters with the dissolution medium and almost 70% drug was dissolved within 4 hr. In case of phosphate buffer pH 6.8, the printed capsule showed a longed swelling behaviour up to 12 hr and then gradually bursting of capsule occurred wherein more than 90% encapsulated drug was dissolved within 36 hr. Enteric coating of the printed capsule showed similar behaviour in alkaline medium that observed with non-enteric capsule. This indicates the potential application of this printed capsules for both gastric and intestinal specific delayed drug delivery by a single step enteric coating process.

Bioavailability and hepatoprotection enhancement of berberine and its nanoparticles prepared by liquid antisolvent method

The study was devised to prepare berberine nanoparticles by anti-solvent precipitation method and were assessed for their hepatoprotective effect in Male Sprague-Dawley rats against carbon tetrachloride. The pharmacokinetic parameters of the prepared nanoparticles and berberine were evaluated in rabbits. Histopathological studies and blood biochemical analyses were carried out to evaluate the role of both forms of berberine in the experimental animals. Substantial improvement in the liver function test enzymes levels and liver histopathology were achieved in the animals treated with berberine nanoparticles in comparison to the unprocessed berberine whereas, pharmacokinetic parameters for nanoform of berberine were about 3.97 and 3.88 folds higher than that of the unprocessed berberine. The study revealed that the reduction of berberine particle size to nano range improved pharmacokinetic parameters in rabbits. The nano berberine provided better liver protection in experimental rats and high berberine blood concentration. Thus, better hepatoprotective and pharmacokinetics effects were observed for the nano form in comparison to unprocessed form.

Fabrication, optimization, and in vitro/in vivo evaluation of diclofenac epolamine flash tablet

The objective of this work was to design a diclofenac epolamine (DE) flash tablets (FTs) intended to dissolve in the mouth saliva, thereby improving the DE bioavailability and reducing its first-pass liver metabolism. Design-Expert software was used to build a 3¹.2² full factorial design (12 runs). FTs were fabricated using lyophilization process. The dissolution response was selected to pick the optimized run. The results indicate that the optimized run (R1) showed the fastest drug dissolution (total dissolution in 12 min). The predicted run (Rp) showed a desirability of about 0.93. Differential scanning calorimetry(DSC) analysis results showed a decrease in the drug melting point of the R1 formulation. Fourier-transform infrared spectroscopy (FTIR) showed the compatibility of the drug with other components of formulation, X-ray powder diffraction (XRPD) analysis showed the evolution of the drug physical state from a crystalline to an amorphous form and scanning electron microscopy(SEM) divugled the disappearance of drug crystals in gelatin strands. The results of the pharmacokinetic study performed in 6 human volunteers evidenced an increase in the maximum DE concentration in plasma and, consequently, an increased bioavailability of the FT formulation as compared with a reference formulation(Fr). Concisely, the developed FTs (R1) showed promising results which could be able to enhance oral bioavailability, reduce the therapeutic dose of the drug, and abate of the complications accompanied with conventional dosage forms. Graphical abstract.

Challenges and innovations of drug delivery in older age

Both drug delivery performance and various age-related physical, mental and physiological changes can affect drug effectiveness and safety in elderly patients. The many drug delivery systems developed over the years include recent novel transdermal, nasal, pulmonary and orally disintegrating tablets that provide consistent, precise, timely and more targeted drug delivery. Certain drug delivery systems may be associated with suboptimal outcomes in the elderly because of the nature of drug present, a lack of appreciation of the impact of age-related changes in drug absorption, distribution and clearance, the limited availability of pharmacokinetic, safety and clinical data. Polypharmacy, patient morbidity and poor adherence can also contribute to sub-optimal drug delivery systems outcomes in the elderly. The development of drug delivery systems for the elderly is a poorly realised opportunity, with each system having specific advantages and limitations. A key challenge is to provide the innovation that best meets the specific physiological, psychological and multiple drug requirements of individual elderly patients.

Developments in Taste-Masking Techniques for Traditional Chinese Medicines

A variety of pharmacologically active substances, including chemotherapeutic drugs and the substances from traditional Chinese medicine (TCM), always exhibit potent bioactivities after oral administration. However, their unpleasant taste (such as bitterness) and/or odor always decrease patient compliance and thus compromise their curative efficacies in clinical application. Therefore, the developments of taste-masking techniques are of great significance in improving their organoleptic properties. However, though a variety of taste-masking techniques have been successfully used to mask the unpalatable taste of chemotherapeutic drugs, their suitability for TCM substances is relatively limited. This is mainly due to the fact that the bitter ingredients existing in multicomponent TCM systems (i.e., effective fractions, single Chinese herbs, and compound preparations) are always unclear, and thus, there is lack of tailor-made taste-masking techniques to be utilized to conceal their unpleasant taste. The relevant studies are also relatively limited. As a whole, three types of taste-masking techniques are generally applied to TCM, including (i) functional masking via sweeteners, bitter blockers, and taste modifiers; (ii) physical masking via polymer film-coating or lipid barrier systems; and (iii) biochemical masking via intermolecular interaction, β-cyclodextrin inclusion, or ion-exchange resins. This review fully summarizes the results reported in this field with the purpose of providing an informative reference for relevant readers.

A Novel Method to Mask the Bitter Taste of Berberine Hydrochloride: Powder Surface Modification

Background:

Berberine hydrochloride (BH) is widely used as a nonprescription drug to treat diarrhea without drug resistance and side effects worldwide. However, its drastic bitterness affects patient compliance severely. Hence, it is essential to mask the bitter taste of BH.

Objective:

Powder surface modification technology is attempted to mask the bitterness of BH through changing the surface properties in vibromill. The purpose of this study was to apply this technology to mask the bitterness of BH and improve the patient compliance.

Materials and Methods:

Initially, to prepare the modifier-BH composites, some parameters were optimized, including type of modifiers, ratio between BH and modifiers, and composite time. Then, the contact angles, scanning electron microscopy, and infrared (IR) spectroscopy were utilized to evaluate the microstructure of composites. Moreover, electronic tongue measurement, animal performance test, and bitterness evaluation methods were applied to evaluate the masking effect.

Results:

Based on the results of bitter taste evaluations, mannitol was chosen as the best modifier, and the optimal ratio of BH and mannitol was 6:4 with grinding together for 2 min in vibromill. For the composites prepared by this process, the IR spectroscopy and surface properties were similar with that of mannitol, and the microstructure was also demonstrated that small particles of mannitol successfully coated on the surface of BH. Special structure of the composites decreased the contact area between BH and external media and finally inhibited the bitterness. This effect was confirmed by three different kinds of methods.

Conclusion:

Our study provides a novel method to mask the bitter taste of drugs. It will be of great interest to pharmaceutical experts and pharmacists.

SUMMARY

Powder surface modification, a novel and different from previous technology, is used to prepare modifier-berberine hydrochloride composites to mask the bitter taste of BH

Electronic tongue measurement, animal performance test, human sensory test, and chemical evaluation method were simultaneously applied to evaluate the masking effect

A novel method to mask the bitter taste of drugs was provided.

Abbreviations used: BH:Berberine hydrochloride; CDI: Clostridium difficile infection; ODT: Orally disintegrating tablets; HPLC: High-performance liquid chromatography; CAs: Contact angles; SEM: Scanning electron microscopy; IR: Infrared spectrogram.

A novel and discriminative method of in vitro disintegration time for preparation and optimization of taste-masked orally disintegrating tablets of carbinoxamine maleate

The primary objective of this study was to mask bitter taste and decrease the disintegration time of carbinoxamine maleate (CAM) orally disintegrating tablets (ODTs). In order to screen the prescription of ODTs, a novel modified in vitro disintegration method (MIVDM) was developed to measure the in vitro disintegration time. In this method, different concentrations of ethanol served as disintegration medium in order to delay the in vitro water absorption and disintegration process of tablets. The MIVDM demonstrated good in vitro and in vivo correlation and proved more precise and discriminative than other reported methods. In this research, ion exchange resins (IERs) were used to mask bitter taste for improving mouthfeel. The drug-resin ratio and reaction temperature were investigated to obtain the optimum carbinoxamine resin complexes (CRCs). The characterization of CRCs revealed an amorphous state. ODTs were prepared by direct compression. Superdisintegrants and diluents of ODTs were screened first. Further optimization was carried out by using Box-Behnken design. The effect of (X₁) mannitol/microcrystalline cellulose ratio, (X₂) the amount of low-substituted hydroxypropylcellulose and (X₃) the hardness was investigated for achieving the lowest (Y) in vitro disintegration time. Technological characterization, wetting time, water absorption ratio, and roughness degree were evaluated. The CRCs and ODTs proved successful taste-masking efficiency. The end product improved patients' compliance. The developed MIVDM was practical for commercial use.

Microwave-Assisted Development of Orally Disintegrating Tablets by Direct Compression

Orally disintegrating tablets (ODTs) are challenged by the need for simple technology to ensure good mechanical strength coupled with rapid disintegration. The objective of this work was to evaluate microwave-assisted development of ODTs based on simple direct compression tableting technology. Placebo ODTs comprising directly compressible mannitol and lactose as diluents, super disintegrants, and lubricants were prepared by direct compression followed by exposure to >97% relative humidity and then microwave irradiation for 5 min at 490 W. Placebo ODTs with hardness (>5 kg/cm²) and disintegration time (<60 s) were optimized. Palatable ODTs of Lamotrigine (LMG), which exhibited rapid dissolution of LMG, were then developed. The stability of LMG to microwave irradiation (MWI) was confirmed. Solubilization was achieved by complexation with beta-cyclodextrin (β-CD). LMG ODTs with optimal hardness and disintegration time (DT) were optimized by a 2³ factorial design using Design Expert software. Taste masking using sweeteners and flavors was confirmed using a potentiometric multisensor-based electronic tongue, coupled with principal component analysis. Placebo ODTs with crospovidone as a superdisintegrant revealed a significant increase in hardness from ∼3 to ∼5 kg/cm² and a decrease in disintegration time (<60 s) following microwave irradiation. LMG ODTs had hardness >5 kg/cm², DT < 30s, and rapid dissolution of LMG, and good stability was optimized by DOE and the design space derived. While β-CD complexation enabled rapid dissolution and moderate taste masking, palatability, which was achieved including flavors, was confirmed using an electronic tongue. A simple step of humidification enabled MWI-facilitated development of ODTs by direct compression presenting a practical and scalable advancement in ODT technology.

Mechanical microencapsulation: The best technique in taste masking for the manufacturing scale - Effect of polymer encapsulation on drug targeting

Drug taste masking is a crucial process for the preparation of pediatric and geriatric formulations as well as fast dissolving tablets. Taste masking techniques aim to prevent drug release in saliva and at the same time to obtain the desired release profile in gastrointestinal tract. Several taste masking methods are reported, however this review has focused on a group of promising methods; complexation, encapsulation, and hot melting. The effects of each method on the physicochemical properties of the drug are described in details. Furthermore, a scoring system was established to evaluate each process using recent published data of selected factors. These include, input, process, and output factors that are related to each taste masking method. Input factors include the attributes of the materials used for taste masking. Process factors include equipment type and process parameters. Finally, output factors, include taste masking quality and yield. As a result, Mechanical microencapsulation obtained the highest score (5/8) along with complexation with cyclodextrin suggesting that these methods are the most preferable for drug taste masking.

Rapid disintegrating tablets of simvastatin dispersions in polyoxyethylene-polypropylene block copolymer for maximized disintegration and dissolution

The objective of this research was to improve the dissolution of simvastatin and to incorporate it in rapid disintegrating tablets (RDTs) with an optimized disintegration and dissolution characteristics. Polyoxyethylene–polypropylene block copolymer (poloxamer 188) was employed as a hydrophilic carrier to prepare simvastatin solid dispersions (SDs). Fourier transform infrared spectroscopy, differential scanning calorimetry (DSC) and X-ray diffractometry were employed to understand the interaction between the drug and the carrier in the solid state. The results obtained from Fourier transform infrared spectroscopy showed absence of any chemical interaction between the drug and poloxamer. The results of differential scanning calorimetry and X-ray diffractometry confirmed the conversion of simvastatin to distorted crystalline state. The SD of 1:2 w/w drug to carrier ratio showed the highest dissolution; hence, it was incorporated in RDT formulations using a 3² full factorial design and response surface methodology. The initial assessments of RDTs demonstrated an acceptable flow, hardness, and friability to indicate good mechanical strength. The interaction and Pareto charts indicated that percentage of croscarmellose sodium incorporated was the most important factor affecting the disintegration time and dissolution parameter followed by the hardness value and their interaction effect. Compression force showed a superior influence to increase RDT’s porosity and to fasten disintegration rather than swelling action by croscarmellose sodium. On the other hand, croscarmellose sodium was most important for the initial simvastatin release. The results suggest the potential use of poloxamer 188-based SD in RDT for the oral delivery of poor water-soluble antihyperlipidemic drug, simvastatin.

In vitro and in vivo investigation of taste-masking effectiveness of Eudragit E PO as drug particle coating agent in orally disintegrating tablets

CONTEXT

Considering that bitter taste of drugs incorporated in orally disintegrating tablets (ODTs) can be the main reason for avoiding drug therapy, it is of the utmost importance to achieve successful taste-masking. The evaluation of taste-masking effectiveness is still a major challenge.

OBJECTIVE

The objective of this study was to mask bitter taste of the selected model drugs by drug particle coating with Eudragit^® E PO, as well as to evaluate taste-masking effectiveness of prepared ODTs using compendial dissolution testing, dissolution in the small-volume shake-flask assembly and trained human taste panel.

MATERIALS AND METHODS

Model drugs were coated in fluidized bed. Disintequik™ ODT was used as a novel co-processed excipient for ODT preparation. Selected formulations were investigated in vitro and in vivo using techniques for taste-masking assessment.

RESULTS AND DISCUSSION

Significantly slower drug dissolution was observed from tablets with coated drug particles during the first 3 min of investigation. Results of in vivo taste-masking assessment demonstrated significant improvement in drug bitterness suppression in formulations with coated drug. Strong correlation between the results of drug dissolution in the small-volume shake-flask assembly and in vivo evaluation data was established (R ≥ 0.970).

CONCLUSION

Drug particle coating with Eudragit^® E PO can be a suitable approach for bitter taste-masking. Strong correlation between in vivo and in vitro results implicate that small-volume dissolution method may be used as surrogate for human panel taste-masking assessment, in the case of physical taste-masking approach application.

Non-human tools for the evaluation of bitter taste in the design and development of medicines: a systematic review

Taste evaluation is a crucial factor for determining acceptance of medicines by patients. The human taste panel test is the main method used to establish the overall palatability and acceptability of a drug product to a patient towards the end of development. Non-human in vitro and in vivo taste-evaluation tools are very useful for pre-formulation, quality control and screening of formulations. These non-human taste assessment tools can be used to evaluate all aspects of taste quality. The focus of this review is bitterness because it is a key aspect of taste in association with the development of medicines. In this review, recent in vitro (analytical) and in vivo (non-human) tools are described for the assessment of the bitter taste of medicines. Their correlations with human taste data are critically discussed. The potential for their use in early screening of the taste of active pharmaceutical ingredients (APIs) to expedite paediatric formulation development is also considered.