HPMC, for example, has the ability to swell and form a gel layer, which allows control of the drug release rate on the surface of matrix systems, and therefore, it is used in the development of...

2020年8月10日 · The process of hydration of the polymeric structure of HPMC is thermally dependent and significantly influences the formation and the structure of resultant gel. Aqueous HPMC solutions exhibit inverse thermally-induced reversible behavior (sol-gel transitions at rather high temperatures), which is often accompanied by clouding of the solution.

(Hydroxypropyl)methyl cellulose (HPMC) can be used to form gels integrating a w/o microemulsion. The formulation in which a microemulsion is mixed with a hydrated HPMC matrix has been successfully used as a carrier of biocompatible ingredients. However, little is known about the structure of these systems.

Sol-gel transformations in HPMC (hydroxypropyl methylcellulose) are being increasingly studied because of their role in bio-related applications. The thermo-reversible behavior of HPMC is particularly affected by its properties and concentration in solvent media, nature of additives, and the thermal environment it is exposed to.

2021年12月23日 · Aqueous solutions of hydroxypropyl methylcellulose (HPMC) show inverse thermoreversible gelation, i.e., they respond to small temperature variations exhibiting sol–gel transition during heating, and reversibly gel–sol transition during cooling.

Hypromellose in an aqueous solution, like methylcellulose, exhibits a thermal gelation property. That is, when the solution heats up to a critical temperature, the solution congeals into a non-flowable but semi-flexible mass.

2022年9月1日 · Gels are matrices of a gelling agent and a liquid component, forming a three-dimensional network structure characterized by stiffness and elasticity properties. Depending on their composition and preparation method, gels can be classified as hydrogels, organogels, emulgels, bigels, aerogels, xerogels, or cryogels.

2014年10月8日 · The mechanism of the formation of HPS gel is the twine of the double helix of amylose through hydrogen bond during the cooling process. While HPMC is a thermal gel that forms hydrogel at higher temperature and its gel disaggregates at lower temperature, which is different from the common hydrogels, such as gelatin and modified starches [11, 12].

Hydroxypropylmethylcellulose (HPMC) is a precursor of cellulose and is modified with small amounts of propylene glycol ether groups attached to the anhydroglucose terminus of the cellulose. It is a self-hardening hydrogel having silane grafted along the hydroxypropyl methylcellulose grafted with silanol group (Si-HPMC) chains (Fatimi et al., 2008).

2024年5月29日 · HPMC forms flexible and transparent films, making it suitable for coating tablets or encapsulating active ingredients. Hypromellose, on the other hand, forms more brittle films that are less flexible. This difference in film properties can impact the mechanical strength and drug release characteristics of coated tablets.