Study On Alendronate / Calcium Phosphate Cement Composite System

ObjectiveThe treatment of alendronate sodium into calcium phosphate cement,alendronate / preparation of different concentrations of calcium phosphate cement composites,respectively Allen curing process of sodium phosphate on calcium phosphate cement and the influence of the physicochemical properties of the cured by medicine,and experimental study on its body release,release of the composite in vitro MethodPreparation of different concentrations(0.5 wt%,1.0wt%,1.5wt%,2.0wt%,wt%and 2.5,3.0wt%)of calcium phosphate bone cement loading alendronate,respectively using the pH value of electronic test instrument,X ray diffraction,electronic universal testing machine,electric thermostatic water bath,the study of alendronate on physico-chemical phosphate properties of calcium phosphate cement system for scanning electron microscopy and UV spectrophotometry(including pH value,setting time,phase transformation,compressive strength,degradation rate,microstructure and in vitro drug release effect).Results(1)The cement hydration process is affected,in the hydration process,alendronate sodium as drug carrier,adsorption of curing liquid water by curing liquid liquid solid ratio decreased,decreased the process of water,with the increase of alendronate loading,the hydration process of pH composites value decreases,the setting time of variable length;(2)The size of hydroxyapatite crystals decreased with the increase of loading,and the matrix became more compact and porosity decreased;(3)The concentration of the drug has no influence on the phase composition of the final cured product of the composite system;(4)Bone cement loaded with phosphate buffer before the infiltration,the compressive strength of each group are with the increasing addition of drug changes increased first and then decreased,but the compressive strength of the samples after infiltration were better than before the invasion;(5)The degradation rate of bone cement gradually increased with the prolonging of soaking time,and finally stabilized,and the degradation rate increased with the increase of alendronate dose;(6)The addition of the drug did not change the microstructure of the composition of the drug loading system.The microstructure of the samples under the scanning electron microscope was basically similar.Most of the crystals were interlaced with each other and embedded into a network system to form coral like crystals;(7)With the increase of alendronate concentration,the stability of cement paste increased,and the injection ability of bone cement increased obviously;(8)The release of the drug has two stages: sudden release and slow release,which basically conform to the Higuchi diffusion release mechanism.ConclusionIn this study,the effects of alendronate on the operating performance and physicochemical properties of calcium phosphate cement were systematically investigated:(1)During the curing process of the drug delivery system,the hydration process of bone cement changes with the increase of alendronate sodium;(2)The influence of alendronate on the physical and chemical properties ofcalcium phosphate cement is related to the amount of drug addition;(3)Alendronate can be continuously and effectively released in the composite system,and calcium phosphate cement can be considered as a suitable sustained release carrier for alendronate.This study provides a theoretical basis for the experimental and clinical study of alendronate in the calcium phosphate cement sustained release system which can be used as a biodegradable bone substitute material.