Research in Dr Rafaqat’s group is of multidisciplinary nature, he has strong background in Organic chemistry as well as biochemical engineering. Research in his group focuses on hard tissue repair and augmentation.
Following are some of the projects currently being carried out in his group.
Coating of metallic substrates with different bioceramic powders: Metallic surfaces are not bioactive resulting in poor bonding between the implant and the surrounding tissue. Coating of metallic substrates with bioactive materials is a very expensive process and requires use of highly expensive equipment, yet it is very ineffective as substantial amount of powder is wasted and some of the coated material goes through phase transformation due to extremely high temperatures used during the process. As a result of this use of coated metallic implant is a luxury limited to handful of people. Projects under this category aim to establish cost effective methodologies to develop coated implants to be used in the orthopedic surgeries in Pakistan. Manufacturing of these implants in Pakistan can substantially lower their cost and undoubtedly improve the lives of the citizens of Pakistan.
Preparation and characterisation of bioceramics with controlled resorbability: Bone grafting, first established in the 1800s, involves replacement of missing/damaged bone with material from another part of the body of either the patient (autograft) or a donor (allograft). But over the last few decades the use of processed or synthetic bone graft substitute materials has increased exponentially. Hydroxyapatite (HA) is a highly biocompatible material which is chemically similar to the inorganic constituent of natural bone, however, it has a poor resorption rate inside the body. To address this issue biphasic calcium phosphate ceramics (BCP) with different ratios of HA and b-Tri-calcium phosphates (TCP) are being developed to control the resorbability of HA and at the same time maintain its osteoconductive properties. Dissolution rates of BCP’s are being studied to characterise rate of resorption and ascertain biocompatibility of BCP.
Synthesis of Carbon Nanotubes (CNT) and Carbonated Hydroxyapatite composites: HA is used in a range of orthopedic applications from resorbable / non-resorbable disease-free bone replacement material (porous bone grafts) to bone cements and coatings on biomedical implants to promote fixation and osteointegration after surgery. Due to the inferior mechanical properties of HA, its clinical application is limited to non-major load bearing parts of the body, such as the ossicles of the middle ear, dentistry and low load bearing monolithic implants. This project is looking into ways of improving the mechanical properties of HA by preparing composites with CNTs. Modulus, strength and ductility are being studied at a constant rate of strain. SEM is being used to study the monotonic and fatigue fracture surfaces of the composites to discern the mechanisms of failure occurring in the composites.