Development and evaluation of calcium alginate beads prepared by sequential and simultaneous methods

Abstract

The objective of this study was to develop a sustained release dosage form of Trimetazidine dihydrochloride (TMZ) using a natural polymeric carrier prepared in a completely aqueous environment. TMZ was entrapped in calcium alginate beads prepared with sodium alginate by the ionotropic gelation method using calcium chloride as a crosslinking agent. The drug was incorporated either into preformed calcium alginate gel beads (sequential method) or incorporated simultaneously during the gelation stage (simultaneous method). The beads were evaluated for particle size and surface morphology using optical microscopy and SEM, respectively. Beads produced by the sequential method had higher drug entrapment. Drug entrapment in the sequential method was higher with increased CaCl2 and polymer concentration but lower with increased drug concentration. In the simultaneous method, drug entrapment was higher when polymer and drug concentration were increased and also rose to a certain extent with increase in CaCl2 concentration, where further increase resulted in lower drug loading. FTIR studies revealed that there is no interaction between drug and CaCl2. XRD studies showed that the crystalline drug changed to an amorphous state after formulation. Release characteristics of the TMZ loaded calcium alginate beads were studied in enzyme-free simulated gastric and intestinal fluid.<br>O objetivo deste estudo foi desenvolver forma de liberação controlada de dicloridrato de trimetazidina (TMZ) utilizando transportador plomérico natural em ambiente completamente aquoso. A TMZ foi presa em pérolas de alginato de cálcio preparadas com alginato de sódio pelo método de gelatinização ionotrópica, usando cloreto de cálcio como agente de formação de ligações cruzadas. O fármaco foi incorporado nas pérolas de gel de alginato de cálcio (método sequencial) ou incorporado, simultaneamente, durante o estágio de gelificação (método simultâneo). As pérolas foram avaliadas quanto ao tamanho das partículas e morfologia da superfície utilizando microscopia óptica de SEM, respectivamente. As pérolas produzidas pelo método sequencial apresentaram maior capacidade de inclusão. No método sequencial, a inclusão de fármaco foi maior com o aumento de CaCl2 e da concentração do plímero, mas menor com o aumento da concentração de fármaco. No método simultâneo, a inclusão de fármaco foi mais alta quando as concentrações de fármaco e plímero foram aumentadas e, também, atingiram certa extensão com aumento na concentração de CaCl2, cujo aumento posterior resultou em carga menor de fármaco. Estudos de FTIR revelaram que não há interação entre fármaco e CaCl2. Estudos de XRD mostraram que o fármaco mudou do estado cristalino para o amorfo após a formulação. As características de liberação de TMZ das pérolas carregadas com alginato de cálcio foram estudadas em fluidos simulados, gástrico e intestinal, livres de enzima

Formulation and Evaluation of Diazepam-Loaded Intravaginal Alginate Beads: An Investigation Study for the Treatment of Pelvic Floor Dysfunction

“…An increase in the cross-linking agent concentration, led to the formation of more rigid gel structure with smaller pore size, which retained the drug and retarded the penetration of the dissolution medium into the beads which in turn decreased the total amount of the drug released [15]. This was in a good correlation with Mandal et al who reported a significant decrease in the amount of trimetazidine dihydrochloride release from 38% to 30% with an increase in Cacl2 concentration from 1% to 3% [41]. (Fig.…”

Encapsulation characteristics of protein hydrolysate extracted from Ziziphus jujube seed

“…The aqueous solution of calcium chloride was stirred at 4000 rpm. The stirring was continued for 1h, and the calcium alginate beads were harvested by filtration, washed with distilled water, and air-dried overnight [18] .…”

“…The solution was filtered. The filtrate was used for measuring the antioxidant activity, metal chelation activity, and reducing power [18,23] .…”

Ekstraksi Na-Alginat dari Rumput Laut Padina sp. Menggunakan Konsentrasi Kalium Hidroksida yang Berbeda

“…Perbandingan M dan G mempengaruhi laju pembentukan hidrogel dan/atau karakteristik akhir dari hidrogel. Alginat yang mengandung asam guluronat yang tinggi cenderung mempunyai struktur yang kaku (rigid) serta mempunyai porositas yang besar, sedangkan yang mengandung asam manuronat yang tinggi mempunyai struktur yang tidak kaku dan lebih fleksibel (Mandal et al, 2010 …”