Biomaterials and its applications By Dr. P. SANGEETHA Assistant Professor Materials Chemistry Division School of Advanced Sciences VIT University , Vellore.

Biomaterial Definition: A biomaterial is a nonviable material used in a medical device, intended to interact with biological systems Characteristics of biomaterials: 1. Physical Requirements: Hard Materials. Flexible Material. 2. Chemical Requirements Must not react with any tissue in the body. Must be non-toxic to the body. Long-term replacement must not be biodegradable. .

History More than 2000 years ago, Romans, Chinese, and Aztec’s used gold in dentistry. Turn of century, synthetic implants become available. 1937 Poly(methyl methacrylate) (PMMA) introduced in dentistry. 1958, Rob suggests Dacron Fabrics can be used to fabricate an arterial prosthetic. 1960 Charnley uses PMMA, ultrahigh-molecular-weight polyethylend, and stainless steal for total hip replacement. Late 1960 – early 1970’s biomaterial field solidified. 1975 Society for Biomaterials formed.

Bio-materials Science Grow cells in culture. Apparatus for handling proteins in the laboratory. Devices to regulate fertility in cattle. Aquaculture of oysters. Cell-silicon “Biochip”.

Synthetic BIOMATERIALS Polymers Skin/cartilage Drug Delivery Devices Ocular implants Bone replacements Orthopedic screws/fixation Ceramics Metals Heart valves Synthetic BIOMATERIALS Semiconductor Materials Dental Implants Dental Implants Biosensors Implantable Microelectrodes

Applications ofbiomaterials Bileaflet Heart valves Heart Valve Artificial Tissue Dental Implants Intraocular Lenses Vascular Grafts Hip Replacements Artificial Tissue

Dental Implants Small titanium fixture that serves as the replacement for the root portion of a missing natural tooth. Implant is placed in the bone of the upper or lower jaw and allowed to bond with the bone. Most dental implants are: pure titanium screw-shaped cylinders that act as roots for crowns and bridges, or as supports for dentures.

Applications Vascular Grafts Hip Replacements Intraocular Lenses Most Common Medical Practice Using Biomaterials. Corrosion Resistant high-strength Metal Alloys. Very High Molecular Weight Polymers. Made of PMM, silicone elastomer, and other materials. By age 75 more than 50% of population suffers from cataracts. Must Be Flexible. Designed With Open Porous Structure. Often Recognized By Body As Foreign.

Bio-Porous Materials

Artificial Porous Materials

Classification

Activated Carbon derived from bio-materials

Preparation of activated carbon

Pore structure of activated Carbon

Types Powdered activated carbon Granulated Spherical Impregnated carbon Polymer coated carbon

Advanced active carbons Carbon molecular sieves Activated carbon fibres Active carbon fibres for energy applications

Porous carbons are prepared through controlled pyrolysis of carbonaceous materials, naturally occurring woods or synthetic polymeric materials. Though these are used as insulating materials, templates for ceramics etc, but the maximum applications is as active carbon produced by chemical activation or physical activation. Chemical activation results in active carbons with mixed pore structure i.e. micro, meso, macropores; physical activation leads to formation of predominantly micropores with dia<2nm.

These active carbons are prepared in many physical forms and are used as such or after impregnation with metal salts in a large number of applications depending upon imagination. Active carbon fibres are increasingly getting attention because of ease of fabrication, controlled pore structure, higher adsorption capacity, faster adsorption/desorption rates. Active carbon fibres have been tried successfully in number of advanced technologies such as adsorbents, catalyst support, ANG, gas and liquid phase environmental control, water purification and energy storage. There is still wide scope for development of active carbon fibres in various forms with tailored porous structures for desired specific applications.

Bio-porous carbon materials for purification of water Global crisis for water and the problems dealt with water, in need for pure water. ----------Bio-porous carbon materials for water purification. One of the most pervasive problems afflicting people throughout the world is inadequate access to clean water. Problems with water are expected to grow worse in the coming decades, with water scarcity occurring globally, even in regions currently considered water-rich. Addressing these problems calls out for a tremendous amount of research to be conducted to identify robust new methods of purifying water at lower cost and with less energy, while at the same time minimizing the use of chemicals and impact on the environment.

Earlier nanomaterials has been used extensively for purification of water. Recently, porous carbon materials, which are bio based, has got considerable scope towards pure water. Removal of contaminants and recycling of the purified water would provide significant reductions in cost, time, and labor to industry and result in improved environmental stewardship. The world is facing formidable challenges in meeting rising demands of clean water as the available supplies of freshwater are decreasing due to: ….. extended droughts, ….. population growth, …..more stringent health-based regulations, and ….. competing demands from a variety of users

Bio-sensors Biosensors have a wide variety of applications: - glucose monitoring - pesticide detection pathogen detection quantitative measurements of toxicity determination of drug residues in food protein engineering, drug delivery evaluation of biological activity of new compounds

Various techniques for Porous silicon based bio-sensing

Porous bio-ceramics

Acknowledgement Management of VIT University My Students. My Sincere Thanks to Prof. B. Viswanathan, NCCR, IIT-M Prof. S. Sivasanker, Chair Professor, NCCR,IIT-M. Prof. K. Shanthi, Anna University (Supervisor) Prof. P. Selvam, NCCR, IIT-M Prof. Krishnamurthy, NCCR,IIT-M Management of VIT University My Students.

THANK YOU