Tablets and pellets are the most common oral solid dosage forms. Tablets are cost effectively prepared by compression processes. Pellets are further processed by filling into capsules. Tablets are a flexible dosage form as immediate release and extended release tablets are available just by changing the excipients. Both, tablets and pellets may be coated for further functionalization. For example to increase swallow-ability or provide an enteric protection. Shin-Etsu provides excipients to prepare
Immediate release tablets and pellets with L-HPC
Oral dispersible tablets with SmartEx®
Extended release tablets with METOLOSE® SR and TYLOPUR® SR
Film coated tablets and pellets with PHARMACOAT® and TYLOPUR®
Enteric coated tablets and pellets with Shin-Etsu AQOAT® or HPMCP
Amorphous solid dispersion products with Shin-Etsu AQOAT®
Filter applications by:
Film coatings of this type are now in widespread use throughout the world. Although drug properties are the key factor in medicinal formulations, the physical form or the finish of a preparation is also important. PHARMACOAT® and TYLOPUR® hypromellose are easy to use as a film coating material and give an excellent finish. It is very versatile, and is suitable for many applications in the design of film-coated tablet formulations. PHARMACOAT® and TYLOPUR® films have the tough and flexible characteristics of cellulose derivatives. Although hypromellose film is not brittle, as acrylic polymer is, addition of a plasticizer such as polyethylene glycol (PEG 6000) is effective when highly flexible film is required. When PHARMACOAT® and TYLOPUR® films are used for film coating, sometimes titanium dioxide or pigments, as well as talc can be added to provide a smooth and colorful film.
Pellets coating prevents chemical interaction of API and excipients and improves the pellet surface. However regular aqueous film coating agents are of sticky nature and the low weight of pellets might lead to agglomeration during the fluid bed coating process. METOLOSE® SM-4, an extremely low viscosity methyl cellulose is useful for aqueous film coating of pellets since it is less sticky and water soluble.
Taste making of bitter tasting drugs is a common issue in formulation development. Taste masking of fine granules is sometime a major challenge due to the delay in drug release and difficulty of the coating operation. You can use an aqueous coating using METOLOSE® SM-4 without a sticking problem and no delay of dissolution. If you require time release of API after lag time for 5-10 minutes after administration is a feature of the dissolution behavior of sugar coating and such coating is a suitable method for taste masking. Combination of PHARMACOAT® and enteric coating material, such as Shin-Etsu AQOAT® can also be coated on a tablet for taste masking effect.
An enteric coating agent is used to protect drugs from degradation by gastric acid or to protect gastric mucosa from irritating drugs. Thus, an enteric coating agent is insoluble in gastric juice, and it immediately dissolves when the enteric preparation transfers to the small intestine. HPMCP (hypromellose phthalate) and Shin-Etsu AQOAT® (hypromellose acetate succinate) were introduced into the market as an alternative for enteric coating.
Shin-Etsu AQOAT® is a enteric polymer suitable for aqueous polymer coatings. The coating dispersion is prepared with the HPMCAS-“F” fine powder grades to ensure trouble-free rapid coating process. "Dry coating" is a unique technique in which the polymer powder is directly applied to tablets or granules and the powder layer coalesces to form a film quickly by curing. In 2000, a Japanese pharmaceutical company commercialized this technique using Shin-Etsu AQOAT® for the first time. This technique is applicable for both tablets and granules using a regular apparatus with a powder feeding system. Ask your sales representative for further information.
When Shin-Etsu AQOAT® is fully neutralized (e.g. by ammonia), it dissolves completely in the coating media. In this case the “G” granular grades are applied and no surfactant for wetting of the HPMCAS is required, simplifying your formulation.
Adjusting viscosity by blending two grades of Metolose
Solubility of HPMC and MC in organic solvents
Taste masking for fine granules by Metolose and an acrylic polymer
Sustained release (matrix tablets)
Hydrophilic matrix systems designed with water-soluble polymers, such as hypromellose, were first introduced in the early 1970s. Hydrophilic matrix system have allowed more controllable and reproducible drug release by controlling the chemical and physical properties of the polymer. METOLOSE® SR and TYLOPUR® SR (hypromellose) is especially suitable for this application, and provides a genuine consistency in the final products.
Hypromellose 2910, different viscosities 50-10000 mPas
PHARMACOAT®, METOLOSE® and TYLOPUR® can also be used as a binder for granulation. The fine particle size (average 50-70 μm) allows good mixture with the vehicle (lactose/cornstarch) and PHARMACOAT®, METOLOSE® and TYLOPUR® are effective for fluidized bed granulation and high shear mixer granulation (dry-blend).
One of the benefits of L-HPC is to resolve “capping” in immediate release formulations, which is a typical problem in the tableting process. Several reports have highlighted that capping is caused by a high residual die-wall pressure during the tableting process. L-HPC reduces the residual die-wall force and ejection force during the tableting process. For this application we recommend that you use LH-11. However using LH-21, 22 or NBD-020 also acceptable results when better flow is required.
To accelerate API dissolution from immediate release tablets, a quick disintegration into fine particles by fast and strong swelling is preferred. LH-B1 featuring highest swelling rate and pressure among the L-HPC grades gives you the best result.
All L-HPC grades give a fast disintegration of immediate release tablets. However there are differences in swelling rate and pressure. The L-HPC B1 grade with highest swelling rate and pressure gives you the quickest disintegration when a formulation is processed by WG and compressed into tablets
In wet granulation, L-HPC is beneficial in the powder blend to increase binding and compactibility. Among the L-HPC grades, LH-11 and LH-21 are two recommendations for wet granulated immediate release formulations.
Roller compaction is a dry granulation technique. The powder blend requires sufficient binding to form a stable ribbon and larger granules with less fine powders after the milling step. L-HPC NBD-grades are low-substituted hydroxypropyl cellulose and increase the binding properties of your roller compaction formulation. At the same time L-HPC acts as disintegrant ensuring the quick disintegration of your roller compacted IR formulation. Best performance in roller compaction give the compactibility optimized L-HPC NBD grades. LH-31/32 is suitable as well.
L-HPC enhances dissolution from a coated drug layer by its swelling properties. L-HPC 31 and 32 can also be used in powder layering the API, this can be carried out in a centrifugal coater using a PHARMACOAT® / TYLOPUR® binder solution.
As well as tableting, L-HPC is also applicable for pellet extrusion. Micronized grades (typically LH-31) are best suited for this application because smaller particles can easily pass through the screen. L-HPC provides wet mass with a “buffer effect” where the wet mass accepts a wider range of water content. L-HPC plasticizes wet mass and shows greater productivity (extrusion speed and yield). The final pellets show quick disintegration and better friability compared with non-L-HPC formulations.
Orally disintegrating tablets (ODT) differ from traditional tablets in that they are designed to be dissolved in the oral cavity rather than swallowed whole. Shin-Etsu developed a co-processed excipient especially for the ODT application by direct compression. This excipient is named SmartEx®. NBD-022 is our second recommended product for this application as it has the quickest disintegration and a better feeling in the mouth than the other NBD grades.