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Effect of Sodium Carboxymethylcellulose Biopolymer on Sedimentation Properties of Trimagnesium, Tricalcium and Tristrontium Phosphates Precipitates
IBOROMA, SD; COOKEY, GA & OBUNWO, CC
Abstract
Sedimentation data of bioactive materials are essential in formulation of suspension with desirable
requirements. Batch-wise precipitation and sedimentation tests were conducted to evaluate the effect of sodium
carboxymethylcellulose (Na-CMC) biopolymer solution on the sedimentation properties (rate and compaction) of
trimagnesium phosphate (TMP), tricalcium phosphate (TCP) and tristrontium phosphate (TSP) precipitates. Fixed volume
(1ml) of different concentrations (200ppm - 2000ppm) of Na-CMC solution was mixed with fixed volume (50ml) of 0.5M,
0.05M Na3PO4 solutions. Accordingly, the resulting solutions were separately mixed with fixed volumes (50ml) of 0.5M
Mg (NO3)2, 0.05M CaCL2 and 0.05M SrCL2 solutions and settling of the precipitates formed monitored. The results showed
that whereas for TCP, Na-CMC exhibited a curvilinear relationship with precipitate sedimentation, non-linear relationships
were observed for TMP and TSP precipitates. Between 200ppm and 2000ppm of Na-CMC addition, sedimentation rate and
compaction of TCP precipitate increased by 187% and 18.5%, whereas for TMP and TSP precipitates, they increased by
only (19.89% and 1%) and (30% and 0%), respectively. The results suggest that Na-CMC biopolymer is not the preferred
suspending medium for suspension formulations containing TCP. For TMP and TSP precipitates, further study is needed
in the light of the fact that magnesium and strontium resemble calcium.
Keywords
sedimentation rate; compaction; precipates; sodium carboxymethylcellulose
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