Bone Grafts via Bio-mimetic Approach

Patent Filing No.: 983/KOL/2014

Award won
DST Lockheed Martin India Innovation Growth Program Award 2015


Brief description

Healing of complicated bone fractures, fibrous non-unions and severe trauma require additional support material as template to aid the healing process. Material selection and template design depend on physico-mechanical properties of bone/tissues and their regeneration kinetics. Calcium phosphate (CaP) based hybrid composite with non-collagenous polymer (NCP) scaffold becomes a promising approach for bone graft replacement due its structural and functional characteristics relevant to musculoskeletal tissue.

 The present invention relates to compositional aspect, fabrication strategies and three dimensional architectural designs towards skeletal tissue healing. Specifically, synthesis procedure of mono/multiphasic calcium phosphates from biological wastes, phosphorylation of polymers, their applications individually or in combinations towards repairing/regeneration of skeletal tissues and other biomedical means. Besides bioactivity, this hybrid composite containing inorganic phase will offer high elasticity and organic matrix will provide resilience and resistance to failure. Therefore depending on the tissue type, mineral to organic ratio can be altered to match the tissue specific physico-chemical properties. CaP based composite scaffold with phosphorylated polymers have pH buffering effect which control degradation and resorption rate of polymer as well as suppress consecutive acidic degradation. Not only combination of two different phases, but also their organization can be varied with analogues to the bone in terms of pore architecture by various scaffold design approaches. Both the ceramic phase and polymer phase are originated from biological waste material, transformed in to biologically active/relevant material in a cost effective way.

Summary of the technical details

Resorbable, multi-scalar hierarchical, hybrid composite bone graft has been made, comprising of: (a.) an inorganic phase of multiphasic calcium phosphate (CaP) and its derivative thereof, it is biocompatible, osteoconductive, osteoinductive, with plurality of highly interconnected multi-scalar pores. It is synthesized from biological waste materials (egg shells, sea shells, etc.) in a cost effective single step sintering process. It is highly interconnected, microstructural scaffold in the form of 3D printed, fibrous patterned, foam and as spacer. (b.) a second material is a natural origin resorbable functionalized polymer (phosphorylated chitosan and its derivative) or polymer selected from the group comprising polylactic acids, polyglycolic acids, and combinations thereof. Functionalized chitosan synthesized in a novel, time saving, cost effective, microwave irradiator method. Polymer phase fabricated in the form of nanofibrous film, microfilm, fibrous, 3D printed and spacer.

Combination of two phases and their organization varied with analogues to the targeted bone in terms of microstructure and physico-mechanical properties. 

Advantages of this technology

(1)   Innovation is related to design and fabrication of composite scaffold via combinatorial approach towards bone regeneration. 

(2)   Customized bone graft prepared in minimal processing steps with cost effective method.

(3)   Raw materials for both the phases are natural origin and biological waste.

(4)   Combination of two different phases and their organization can be varied with analogues to the targeted bone.

(5)   Composite scaffolds have nano-micro architecture with bone like structural hierarchy.

(6)   Prepared scaffold is bioactive, resorbable, osteoinductive and osteogenic.

Commercial aspects of the technology & Industries benefiting from it

Every year, 5.8 million people die from orthopaedic trauma and related injuries, 95% of these deaths occurring in developing countries. Being a highly populous developing nation, India faces the brunt of orthopaedic related disease and injuries. Moreover, India spends only 4% of its GDP on healthcare sector, which is insufficient. On the other hand, the currently available bone implants are highly expensive and mostly imported. Therefore, in such low resource settings, we need to come up with alternative solutions, that are affordable and equally or more effective. Current available options are slow in healing, required revision surgeries that cause several associated complications as well.

In this context, we have come up with a ‘HYBRID BONE GRAFT’ as bone substitute implant from natural origin biological waste, having rapid integration with host tissue, results in faster healing, following completely reabsorption and no revision surgeries required. Importantly, it is prepared via minimum processing steps, can be customized and scalable process using biological waste, which makes it around 5-10 times less costly and affordable.

The technology is available off-the-shelf and it can be brought to market with nominal investment.