Film forming properties of Cissus pulpunea (Guill and Perr) and Irvingia gabonensis (O'Rorke) gums.

Background: Natural polymers such as gums have gained attention in drug delivery systems due to their availability, compatibility and degradation under natural and physiological conditions.

Objectives: The aim of the present study was to investigate the film forming properties of gums obtained from the stem of Cissus polpunea (Guill and Perr) and the seed of Irvingia gabonensis (O'Rorke).

Material and methods: Gums were extracted from the relevant plant parts and characterized using functional, proximate and elemental properties. Films were prepared by the casting method using gum concentrations of 1-4% w/v and varied with propylene glycol (PG). The films were assessed through physical observation, thickness, swelling power and moisture sorption effects using the relative humidity of 0, 27, 43, 57, 75 and 90%. The gum yielding optimal film properties was used as coating material in ibuprofen tablet formulations. The mechanical and release properties of the tablets were determined.

Results: The functional and proximate properties of gums showed a similarity in the majority of the parameters, but significant (p < 0.05) variation existed in their solubility, while elemental assessment revealed the absence of toxic metals. Generally, the films were homogenous, opaque and demonstrated high swelling power in phosphate buffer, which was pH-dependent. Moisture sorption properties of the gums increased with the increase in relative humidity in the order HPMC < Cissus < Irvingia. Film-coated ibuprofen tablets showed higher mechanical properties and disintegration and dissolution times compared with uncoated tablets.

Conclusions: Cissus and irvingia gums have demonstrated acceptable functional, proximate and elemental properties. Film-coated ibuprofen tablets showed higher mechanical and release properties than was the case in uncoated tablets.