Hydroxypropyl Cellulose CAS 9004-64-2 HPC

For dry processes, such as direct compression and dry granulation, the plastic deformation of the binder is an important factor affecting the dry bonding effect. Compared with other dry adhesives, HPC has a lower glass transition temperature and is more likely to produce plastic deformation. Coupled with a relatively small particle size, it can have more bonding surfaces with materials, resulting in better bonding. Adhesive effect.

For the wet granulation process, in order for the binder solution to exert the best bonding effect, the solution needs to be well spread on the surface of the material, that is to say, the binder solution must have good wettability to the material. . Table 1 shows the wettability of different solutions to the naproxen formulation. It can be seen that the HPC solution has a smaller contact angle and better wettability for hydrophobic materials, so it can form a relatively uniform layer on the surface of the material. Binder film to improve granulation effect. The final compressed tablet hardness also showed that the HPC solution prepared the naproxen tablet with the highest mechanical strength.

It can be seen that whether it is a dry process or a wet process, HPC can be used as the preferred tablet binder. The good plastic deformation of HPC can be used to improve the prescription of tablets with poor compressibility and prone to capping, and can also improve the granulation effect of brittle materials, reduce fine powder, and increase the yield of granules.

Hydrophilic gel matrix system is the most commonly used in modern oral sustained and controlled release system, mainly because its process is relatively simple, mature and does not require special equipment. Hypromellose, hydroxypropyl cellulose, sodium alginate, xanthan gum, polyoxyethylene, etc. are commonly used hydrophilic gel skeleton materials. The gel formed by medium and high molecular weight HPC can better control the drug release. Generally speaking, HPC with fine particle size can hydrate faster and form a gel layer faster, which is beneficial to achieve the purpose of controlling drug release and inhibiting burst release in a short period of time.

The isoproterenol hydrochloride sustained-release tablets developed by YOSHIHARU et al. use spray drying technology to mix HPC and lactose. The hardness and disintegration time of isoproterenol hydrochloride sustained-release tablets increase with the increase of HPC content. As the molecular weight of HPC increases, drug release slows down. The molecular weight and dosage of HPC are important factors affecting drug release rate, even decisive factors.

Harcum et al. used HPC as the skeleton material to prepare phenylpropanolamine sustained-release tablets by dry granulation, and investigated the effects of HPC particle size (coarse particle size HF and fine particle size HXF) and process parameters on the tablet mechanical properties and release As a result, the sustained-release tablet prepared by HPC with fine particle size has higher hardness and better effect of controlling drug release. What’s more interesting is that the dry granulation process parameters have almost no effect on the fine particle size HPC HXF framework system, but have a greater impact on the coarse particle size HPC HF framework system. It can be seen that the fine particle size HPC HXF is prepared for the hydrophilic gel matrix system, which not only can control the drug release more effectively, but also has better tolerance to the process.

For high-dose and highly water-soluble compounds such as metformin hydrochloride, if it is necessary to prepare a hydrophilic gel matrix tablet, a large proportion of polymer is usually required, which brings great difficulties to administration. If HPC is used as the carrier and prepared by hot-melt extrusion, tablets with lower porosity, better sustained-release effect and larger drug loading can be obtained. Due to the good thermoplasticity and low glass transition temperature of HPC, the smooth progress of the hot-melt extrusion process can be ensured when preparing metformin hydrochloride sustained-release tablets with high drug loading.

With the increasing proportion of poorly soluble drugs, the solubilization challenges faced by formulation developers are also increasing. For solid preparations, micronization of raw materials or adding super disintegrants such as crospovidone into the prescription are simple and effective solubilization means. R. Talukder et al. found another solubilization method that is rarely reported, that is, directly adding HPC or co-grinding raw materials with HPC in the formulation of insoluble drugs to achieve a better solubilization effect. The solubilization of HPC has a lot to do with its small surface tension and good wettability.

In addition, because HPC has a low glass transition temperature and good thermoplasticity, it can be operated smoothly without adding plasticizers, and it is a good carrier for hot-melt extrusion technology.

For mucoadhesive drug delivery systems, it is very important to ensure the residence time of the formulation at the site of administration. Wu Yunjuan et al. added HPC to Panax notoginseng saponins nasal spray, prolonging the residence time of the preparation in the nasal mucosa, increasing the drug absorption, and overcoming the low bioavailability of oral preparations, and the safety and patient compliance problems of injections. . An effective local chemotherapy method to treat superficial bladder cancer and prevent tumor recurrence is to infuse the bladder with anticancer drugs, usually an aqueous solution of anticancer drugs, which not only requires repeated and large-dose infusions, but also may cause bladder irritation, hematuria, Side effects such as bladder atrophy, and drug resistance is easy to develop, and the curative effect is poor. In order to solve the problem that Zhao Guofang and others used the mucoadhesive agent HPC and the anticancer drug MMC to make a mucoadhesive anticancer drug, MMC relies on the mucoadhesive effect of HPC, and can stay in the bladder for a long time, making the half-life of MCC in urine Prolonged by 4.7 times, which may improve the curative effect and reduce the dosage and frequency of drug application.

Due to its good plasticity and film-forming properties, HPC is also widely used in film coating formulations. For the membrane control agent, HPC can not only act as a porogen, but also as a plasticizer. In addition, HPC has many applications in suspension and thickening.