Heat generating biocompatible ceramic materials for drug delivery

Abstract

The present invention pertains to injectable heat generating biocompatible ceramic compositions based on hydraulic calcium aluminate, which can be used for therapeutic treatment in vivo, such as tumour treatment, pain control, vascular treatment, drug activation etc, when curing in situ, and which form a biocompatible solid material that can be left in the body for prolonged periods of time without causing negative health effects. The present invention can also be used to restore the mechanical properties of the skeleton after cancerous diseases.

1 . A drug carrier for drug delivery in a patient's body comprising: 
 a biocompatible ceramic composition, wherein,    said biocompatible ceramic composition comprises a calcium aluminate mixture of (i) less than 50 vol. %, but greater than 0%, of CA 2  (ii), more than 50 vol. % of CA and C 12 A 7 , and less than 10 vol. %, but greater than 0%, of C 3 A as a hydraulic ingredient,    said biocompatible ceramic composition generates heat so as to activate drugs in a patient's body.    
   
   
       2 . The drug carrier according to  claim 1 , wherein said calcium aluminate mixture is at least 50 vol % of all hydraulic ingredients of said biocompatible ceramic composition.  
   
   
       3 . The drug carrier according to  claim 1 , wherein said biocompatible ceramic composition generates temperatures of 30-150° C. when cured.  
   
   
       4 . The drug carrier according to  claim 1 , wherein said biocompatible ceramic composition further comprises at least one of calcium silicate and calcium sulfate in amount less than 50 vol. % of all hydraulic ingredients of said biocompatible ceramic composition.  
   
   
       5 . The drug carrier according to  claim 1 , wherein said biocompatible ceramic composition further comprises particles or a powder of one or more biocompatible materials selected from the group consisting of calcium carbonate, calcium phosphate, apatite, fluoroapatite, carbonates-apatites, and hydroxyapatite in a total amount less than 30 vol. % of the total volume of said biocompatible ceramic composition.  
   
   
       6 . The drug carrier according to  claim 1 , wherein said biocompatible composition further comprises a component which is a water reducing agent selected from the group consisting of polycarboxylic acids, polyacrylic acids, and superplasticisers.  
   
   
       7 . The drug carrier according to  claim 1 , wherein said biocompatible composition further comprises expansion controlling additives.  
   
   
       8 . The drug carrier according to  claim 1 , wherein said biocompatible composition further comprises a water-based curing liquid.  
   
   
       9 . The drug carrier according to  claim 8 , wherein, 
 said curing liquid further comprises an accelerator agent which accelerates hardening of said biocompatible ceramic composition, and    said accelerator agent is selected from the group consisting of lithium chloride, lithium hydroxide, lithium carbonate, lithium sulphate, lithium nitrate, lithium citrate, calcium hydroxide, potassium hydroxide, potassium carbonate, sodium hydroxide, sodium carbonate, sodium sulphate and sulfuric acid.    
   
   
       10 . The drug carrier according to  claim 9 , wherein said accelerating agent is LiCl present in an amount of 10-500 mg in 100 g of said curing liquid.  
   
   
       11 . The drug carrier according to  claim 8 , wherein, 
 said curing liquid further comprises a retarder agent which retards hardening of said biocompatible ceramic composition, and    said retarder agent is selected from the group consisting of polysaccharide, glycerine, sugars, starch, and cellulose-based thickeners.    
   
   
       12 . The drug carrier according to  claim 1 , wherein said biocompatible composition is cured.