The aim of this thesis was to evaluate effect of interactions between the sodium lauryl sulfate (SDS) and hydroxypropylmethylcellulose (HPMC) on swelling and release of diclofenac sodium (NaDF) from matrix tablets with HPMC. The media used in dissolution and swelling tests were concentrated (KMB) and four times diluted (DMB) McIlvaine buffer with pH 4 and addition of SDS in the concentration range of 0 to 0,25 w/V %. We used two types of tablets with HPMC – tablets with and without NaDF. The experiments were performed using paddle apparatus (Apparatus II) as described in Pharmacopoeia with video recording system DissoGUARD® placed underneath the dissolution bath and with 900 mL of medium at 37 ± 0,5 °C and 75 rpm. Tablet swelling was evaluated using two different methods – measuring the dimensions on photos taken between the dissolution testing and tablet weighing.
In DMB tablets with NaDF swelled more at SDS concentrations bellow CMC value (0,05–0,07 % SDS) and the most in DMB with 0,05 % SDS. At this concentration the percentage of NaDF dissolved was the lowest. The highest amount of NaDF was released in DMB with 0,25 % SDS where tablets swelled the least. Tablets with NaDF disintegrated in KMB with added SDS, so swelling could not be measured. We assume that surplus solubility was achieved after tablets disintegrated, consequently concentration of NaDF decreased with time. Larger SDS concentrations in KMB released more NaDF after 4 hours in whole concentration range, except in concentration range from 0,07 % to 0,09 % SDS. In contrast, larger SDS concentrations in DMB released more NaDF after 4 hours only in concentration range from 0,05 % to 0,25 % SDS. The dissolution of NaDF in DMB with 0,01 % SDS was higher than in DMB with 0,05 % SDS. We noticed deviations at the following concentrations: 0,05–0,06 % SDS in DMB and 0,07–0,09 % SDS in KMB which we ascribed to SDS and HPMC interactions.
Swelling of tablets without NaDF was examined under the same conditions as tablets with NaDF during dissolution testing only without sampling. The 4 hour swelling test showed that interim weighing of tablets during the dissolution testing resulted in larger tablets dimensions and masses than weighing tablets just after 4 hours. The 4 and 24 hour test in KMB showed tablets without NaDF swelled the most in media with 0,05 % SDS. In DMB the largest increase in thickness of tablets without NaDF was observed in media with 0,07 % SDS and the largest increase in mass was observed in 0,05 % SDS. Similar swelling results of tablets with and without NaDF show NaDF does not affect swelling process in DMB. Therefore deviations in concentration range from 0,05 % to 0,07 % SDS may be attributed to SDS and HPMC interactions.
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