PMC:7561592 / 13824-15476 JSONTXT

{"project":"2_test","denotations":[{"id":"33063245-29380369-28136","span":{"begin":552,"end":554},"obj":"29380369"},{"id":"33063245-15497676-28137","span":{"begin":1097,"end":1099},"obj":"15497676"}],"text":"Dissolution studies were performed with a mini-paddle apparatus (Agilent Technologies 708-DS apparatus configured with TruAlign 200-mL vessels and electropolished stainless steel mini-paddles; Agilent, USA). Experiments were conducted in a two-stage approach: in SGFsp pH 1.2 (total volume with sample: 100 mL), for 1 h, followed by SIFsp pH 6.8 (final volume: 200 mL), for 3 h. A dissolution study with a sequential media change mimics the passage of oral dosage forms through the GI tract, providing an understanding of the in vivo drug performance (28). Experiments were conducted at 37 ± 0.5°C and the agitation rate of the mini-paddle was set to 50 revolutions per minute (rpm). Sample collection took place at 5, 15, 30, 45, 60, 75, 90, 120, 180 and 240 min. Two-millilitre samples were withdrawn (with volume replacement with the corresponding media), using a 2-mL glass syringe (Fortuna Optima® fitted with a stainless tubing) through a cannula fitted with a full flow filter (10 μm). All experiments were performed without direct light exposure to avoid photodegradation of the drugs (29,30). After collection, samples were filtered through a GF/D (2.7 μm) filter and treated. Sample treatment was as follows: 1000 μL of acetonitrile (montelukast) or 10% (v/v) TFA/water (mesalazine) were added to 500 μL of sample. This mixture was vortexed (HTZ, UK) for 1 min and centrifuged (8000 rpm, 15 min, 4°C) (Beckman Coulter J2-MC centrifuge, UK). The supernatant was filtered through a RC (montelukast) or PTFE (mesalazine) (0.45 μm) filter, placed in an HPLC amber vial and analysed. The pH of the media was measured at the end of each experiment."}