Formation of shellac succinate having improved enteric film properties through dry media reaction

Synthesis and characterization of new shellac–hydroxypropylmethylcellulose composite for pharmaceutical applications

“…The methylene (-CH 2 ) group of protons were also observed in the range d H 2.4-2.5 ppm. [33]. The presence of methine (-CH-OH) group of protons were observed at d H 3.4 ppm (supporting information, Fig.…”

“…Shellac shows the presence of hydroxyl group, m(O-H) str , at 3450 cm -1 . The peak at 1100 cm -1 indicates the presence of ester linkage of shellac moiety [33]. On the other hand, the spectra of Sh-HPMC shows distinct band of hydroxyl group in the range of 3300-3450 cm -1 .…”

Going Natural: Using polymers from nature for gastroresistant applications

“…Although the results by Limmatvapirat et al (2008), Fraser and Young (2010), Ravi et al (2008) and Young (2006) using shellac as a possible enteric coating are promising, these may be different when a different media simulating intestinal conditions is used. Studies using bicarbonate buffer or other simulated intestinal fluids would thus provide a more comprehensive drug release profile.…”

“…Limmatv-apirat et al (2008) developed a modified form of shellac (shellac succinate) in an attempt to improve its solubility in the small intestine. The unmodified shellac presented good gastric resistance in the fasted state, however it is not readily soluble at the small intestinal pH (Limmatvapirat et al, 2008;Ravi et al, 2008). The authors suggest that esterification with succinic anhydride, and the change in annealing time, made it possible to control the pH at which the polymer dissolves.…”

Process and Kinetic Mechanism of Elimination of Chlorine Combined in Molecule of Bleached Shellac

“…The shellac resin is also widely employed in the pharmaceutical industry [11][12][13][14]. It can develop the dosage of a drug released in forms of sustained and/or site specific means while shellac is used as enteric film polymers of drug [15][16][17]. However, in the bleaching process for refining shellac, chlorine is added to the double bonds of shellac molecular structure, and combined chlorine is formed in the final products.…”