Matrix Tablets Based on Chitosan–Carrageenan Polyelectrolyte Complex: Unique Matrices for Drug Targeting in the Intestine

Abstract

The present study focused on the more detailed characterization of chitosan–carrageenan-based matrix tablets with respect to their potential utilization for drug targeting in the intestine. The study systematically dealt with the particular stages of the dissolution process, as well as with different views of the physico-chemical processes involved in these stages. The initial swelling of the tablets in the acidic medium based on the combined microscopy–calorimetry point of view, the pH-induced differences in the erosion and swelling of the tested tablets, and the morphological characterization of the tablets are discussed. The dissolution kinetics correlated with the rheological properties and mucoadhesive behavior of the tablets are also reported, and, correspondingly, the formulations with suitable properties were identified. It was confirmed that the formation of the chitosan–carrageenan polyelectrolyte complex may be an elegant and beneficial alternative solution for the drug targeting to the intestine by the matrix tablet.

Effects of Alkaline Solvent Type and pH on Solid Physical Properties of Carrageenan from Eucheuma cottonii

“…A higher sulphate content resulted in a higher viscosity [29], which is due to the ability of the sulphate group in carrageenan to exert a repulsion force between negative charges along the polymer chain. As a result, the molecular chain stiffens so that the viscosity increases [22,39]. This finding supports the viscosity data in Table 2, where KOH pH 13, NaOH pH 9, and Ca(OH) 2 pH 13 revealed the highest sulphate levels among other pHs of the same type of alkali.…”

“…Carrageenan, with low molecular weight, produces tensile strength, gel strength, and resistance to dynamic mechanical and thermal analysis [16]. The physicochemical characteristics of carrageenan determine its function as an excipient in pharmaceutical preparations, e.g., as a gelling agent, suspending agent, emulsifier, tablet matrix, binder, and disintegrating tablets or granules [17][18][19][20][21][22]. Carrageenan has the characteristics of being able to form gels, increase viscosity, absorb water, and expand [23][24][25][26][27].…”

Designing an effective dissolution test for bilayer tablets tailored for optimal melatonin release in sleep disorder management

“…During the last decades, a huge number of modified release systems have been developed, as they display several advantages over conventional systems used in therapeutics ( 12–15 ). One of the most common methods involves the use of various excipients during tablet manufacturing to enable controlled release ( 16 ). These excipients usually involve hydroxypropylmethylcellulose, polyvinylpyrrolidone, and sodium alginate in various molecular weights or forms ( 5 ).…”