Chitosan-Based Delivery Systems Loaded with Glibenclamide and Lipoic Acid: Formulation, Characterization, and Kinetic Release Studies

Abstract

Glibenclamide and lipoic acid are two drugs frequently recommended for the management of diabetes mellitus, and so, the development of a new formulation containing both substances has a great benefit in terms of efficiency and compliance, acting also as a multi-target drug system. Accordingly, the aim of this study was the formulation and physicochemicalcharacterization of new polymeric systems based on chitosan (CS) in whose matrix were encapsulated glibenclamide (Gly) and lipoic acid (LA). The polymeric systems were prepared as microparticles (CS–Gly, CS–LA, and CS–Gly–LA) through ionic gelation method, using pentasodium tripolyphosphate (TPP) as crosslinking agent. The polymeric systems obtained were characterized in terms of particle size and morphology, IR spectroscopy, entrapment efficiency and drug loading, swelling degree, and therelease of the active substances from the chitosan matrix. The polymeric systems obtained were stable systems; the presence of glibenclamide and lipoic acid into the polymer matrix were proved by IR spectroscopy. The entrapment efficiency was 94.66% for Gly and 39.68% for LA. The developed polymeric systems proved a favorable swelling degree and drug release profile, the percentage of release being 88.68% for LA and 75.17% for Gly from CS–Gly–LA systems.

Simultaneous Determination of Glibenclamide and Silymarin Released from Chitosan Microparticles by HPLC-ESI-MS Technique: Method Development and Validation

“…The mixture was stirred for 5 h and then kept at room temperature for 12 h to complete the crosslinking process. Finally, the obtained CS-Gli-Sil microparticles were washed 3 times with distilled water to remove TPP and allowed to dry on a flat surface at room temperature until further determinations [ 31 ]. Separately, a 1.2% CS solution was prepared in water and 2% TPP was used as a crosslinking agent, leading to the formation of stable microparticles with optimal morphological characteristics.…”

“…After each analysis, fresh fluid (1 mL) was added in order to maintain reaction volume. The released concentrations were calculated based on the calibration curve equations of all the active substances used, and the active substances’ DR% from the polymeric matrix was determined using the following equation [ 31 ]: where c 0 —initial active substance concentration in CS-Gli-Sil (mg/mL); c 1 —active substance concentration released at a given time interval (mg/mL).…”

Kinetics, Equilibrium, and Thermodynamics for Conjugation of Chitosan with Insulin-Mimetic [meso-Tetrakis(4-sulfonatophenyl)porphyrinato]oxovanadate(IV)(4−) in an Aqueous Solution

“…Using the following expressions, 67 the thermodynamic parameters of VO(tpps) conjugation with chitosan, including variations in Gibb's free energy (ΔG), entropy (ΔS), and enthalpy (ΔH), were estimated. (19) where a L , T, and R have the same meaning as previously mentioned. By plotting lna L versus 1/T (R 2 = 0.987; figure not given), the slope and intercept were employed to estimate the extent of enthalpy (ΔH) and entropy (ΔS), respectively.…”

“…In biotechnology, enzymatic catalysis, medicine, and therapeutics, the conjugation of polymer with bioactive molecules has attracted considerable scientific interest . Intensive research is being conducted to develop polymer-based therapeutic systems. , Polymer conjugation increases the therapeutics’ stability and efficacy . In the formulation of therapeutic agents, various polymers such as poly­[ N -(2-hydroxy-propyl)­methacrylamide], polyacrylamide, poly­(vinyl alcohol), poly­(γ-glutamic acid), and chitosan have been utilized as carriers.…”

“…Due to its high mucoadhesiveness and minimal production cost, chitosan is frequently used as a carrier for oral therapeutics . Chitosan-based therapeutic strategies are regarded as a viable method for managing diabetes. − …”