Influence of Sodium Alginate on Hypoglycemic Activity of Metformin Hydrochloride in the Microspheres Obtained by the Spray Drying

Abstract

Alginate microspheres with metformin hydrochloride were prepared by the spray drying method in order to improve residence time of drug in the stomach. Nine formulations (F1–F9) with various drug : polymer ratio (1 : 2, 1 : 1, and 2 : 1) and different sodium alginate concentration (1%, 2%, and 3%) were evaluated for size, morphology, drug loading, Zeta potential, and swelling degree.In vitrodrug release, mathematical release profile, and physical state of microspheres were also evaluated. Optimal formulation characterized by the highest drug loading was formulation F6 (drug : polymer ratio 2 : 1 and 2% alginate solution). Based on glucose uptake inSaccharomyces cerevisiaecells andα-amylase inhibition tests, it could be concluded that alginate microspheres enhance hypoglycemic activity of metformin hydrochloride evaluatedin vitro. Designed microspheres are promising as alternative, multicompartment dosage form for metformin hydrochloride delivery.

Alginate: Current Use and Future Perspectives in Pharmaceutical and Biomedical Applications

“…Owing to mucoadhesive properties, ALG are regarded as proper polymer excipients to prepare buccal [97][98][99], nasal [100,101], ocular [102,103], and gastrointestinal dosage forms [104][105][106][107][108]. Recently, several studies have shown favourable mucoadhesiveness of ALG-based applications in contact with vaginal mucosa tissue [108,109].…”

“…ALG are also considered as promising candidates in obesity and type 2 diabetes treatment as they are able to attenuate the postprandial glycemic response by modulation of gastric emptying [135][136][137][138] or inhibition of glucose transporters and glucose intestinal absorption rate [137]. Additionally, there are studies which have also revealed that ALG mode of hypoglycemic action might be associated with the reduced activity of -amylase, intestinal enzyme responsible for hydrolyzing the bonds between glucose residues in carbohydrate polymers [106,139].…”

The Influence of Chitosan Cross-linking on the Properties of Alginate Microparticles with Metformin Hydrochloride—In Vitro and In Vivo Evaluation

“…Zeta potential is a parameter which enables predicting the stability of formulations [ 26 ]. ALG is an anionic polymer with negative charge, and chitosan as cross-linking agent changed Zeta potential [ 25 , 27 ] from negative (−1.3 ± 0.7 mV) to positive values (6.7 ± 1.3 mV for CH1M and 5.2 ± 0.3 mV for CH2M).…”

“…The composition of designed chitosan cross-linked ALG microparticles was presented in Table 6 . Based on the preliminary studies, 2% ( w/w ) ALG solution and MF:ALG ratio 2:1 were used [ 25 ]. As cross-linking agent, 0.5%, 0.1% and 0.05% ( w/w ) chitosan solutions in 1% acetic acid were applied.…”

“…In our earlier work it was observed that ALG microspheres with MF prepared by the spray-drying method possessed good swelling and mucoadhesive properties, but the drug release profile was prolonged only up to 4 h [ 25 ]. Therefore, in order to obtain more sustained drug release, developing and evaluating for the first time, the possibility of preparing chitosan cross-linked ALG microparticles containing MF by the spray-drying technique was examined.…”