The effect of processing variables on the mechanical and release properties of tramadol matrix tablets incorporating Cissus populnea gum as controlled release excipient.
BACKGROUND
Natural gums are polymers widely used as excipients in drug formulation. Polymer extraction and formulation processing methods could significantly affect formulation characteristics.


OBJECTIVE
To evaluate different methods of gum extraction and the effect of different compression methods on the mechanical and release properties of tramadol hydrochloride matrix tablets incorporating cissus gum as controlled release polymer.


METHODS
Water (CW) and acetone (CA) extracts of cissus gum were obtained from Cissus populea stem and two methods - wet granulation and direct compression - were used to compress the tablet and compare it with xanthan gum (X) formulations. Crushing strength and friability were used to assess mechanical properties while dissolution rate were used to assess release properties. Data were analysed using t-test and ANOVA at p < 0.05.


RESULTS
The crushing strength of tramadol tablets has increased together with the increase in polymer concentration in all formulations, while friability has decreased for both methods. Tablets made by wet granulation had higher crushing strength than those made by direct compression method. The release mechanism for both direct compression and wet granulation methods was Fickian and non-Fickian respectively. The rank order for t25, t50 and t75 for all formulations was X > CA > CW. Generally, wet granulation method decreased the rate of tramadol release more than direct compression method, indicating a higher drug retarding ability.


CONCLUSIONS
Incorporation of cissus gum controlled the release of tramadol hydrochloride from the matrix tablets. Extraction method and formulation variables influenced mechanical and release properties of the tablets. Cissus gum acetone extract had comparable release properties with xanthan gum and could serve as a cheaper alternative in controlled release tablet formulations.
Department of Pharmaceutics and Pharmaceutical Technology, Olabisi Onabanjo University, Ago-Iwoye, Ogun State, Nigeria.
Olutayo Ademola
OA
Adeleye
Department of Pharmaceutics and Pharmaceutical Technology, Olabisi Onabanjo University, Ago-Iwoye, Ogun State, Nigeria.
Mbang Nyong
MN
Femi-Oyewo
Department of Pharmaceutics and Industrial Pharmacy, University of Ibadan, Ibadan, Oyo State, Nigeria.
Michael Ayodele
MA
Odeniyi
D000284:Administration, Oral; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D000704:Analysis of Variance; D002626:Chemistry, Pharmaceutical; D032422:Cissus; D003692:Delayed-Action Preparations; D005079:Excipients / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics; D053149:Plant Gums / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics; D012995:Solubility; D013607:Tablets; D014147:Tramadol / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics*
D000701:Analgesics, Opioid; D003692:Delayed-Action Preparations; D005079:Excipients; D010936:Plant Extracts; D053149:Plant Gums; D013607:Tablets; D014147:Tramadol