Monday, 21 May 2018

Hydrogel Biomaterials:


Hydrogels are water-swollen polymeric materials that maintain a distinct three-dimensional structure. They were the first biomaterials designed for use in the human body . Traditional methods of biomaterials synthesis include crosslinking copolymerization, crosslinking of reactive polymer precursors, and crosslinking via polymer-polymer reaction. These methods of hydrogel synthesis were limited in the control of their detailed structure. Due to side reactions the networks contain cycles, unreacted pendant groups, and entanglements. Other inadequacies of traditional hydrogels have been poor mechanical properties and slow or delayed response times to external stimuli . Novel approaches in hydrogel design have revitalized this field of biomaterials research. New ideas on the design of hydrogels with substantially enhanced mechanical properties, superporous  and comb-type grafted hydrogels  with fast response times, self-assembling hydrogels from hybrid graft copolymers with property-controlling protein domains, and from genetically engineered triblock copolymers are just a few examples of hydrogel biomaterials with a smart future.




Friday, 18 May 2018

Biodegradable polymers as Biomaterials


Biomaterials are used in prostheses and medical devices for different purposes. Polymers are the most diverse class of biomaterials. All biomaterials must meet certain criteria and regulatory requirements before they can be qualified for use in medical applications. Biocompatibility is one of the most important requirements. Both nondegradable polymers are designed to degrade in vivo in a controlled manner over a predetermined time. The main mechanism of in vivo degradation of polymers is ‘hydrolytic degradation’, in which enzymes may also play a role (i.e. ‘enzymatic degradation’). Both natural e.g., collagen, and synthetic e.g., poly(alpha-hydroxy) acids, biodegradable polymers are used in biomedical applications. Many of the current polymers and processing techniques need to be improved in order to produce polymers with better performance in biological media. An important trend in related research and development is the synthesis of novel polymers, which would exhibit improved biocompatibility, and be bioresponsive.




Thursday, 17 May 2018


The design of biomimetic materials for biomaterials and tissue engineering applications that are capable of eliciting specific cellular responses and directing new tissue formation mediated by biomolecular recognition, which can be manipulated by altering design parameters of the material. Biomolecular recognition of materials by cells has been achieved by surface and bulk modification of biomaterials via chemical or physical methods with bioactive molecules such as a native long chain of extracellular matrix (ECM) proteins as well as short peptide sequences derived from intact ECM proteins that can incur specific interactions with cell receptors. The biomimetic materials potentially mimic many roles of ECM in tissues. For example, biomimetic scaffolds can provide biological cues for cell–matrix interactions to promote tissue growth, and the incorporation of peptide sequences into materials can also make the material degradable by specific protease enzymes. This discusses the surface and bulk modification of biomaterials with cell recognition molecules to design biomimetic materials for tissue engineering. The criteria to design biomimetic materials such as the concentration and spatial distribution of modified bioactive molecules are addressed. Recent advances for the development of biomimetic materials in bone, nerve, and cardiovascular tissue engineering are also summarized.

Wednesday, 16 May 2018


Gene Therapy :

Gene therapy is an experimental technique that uses genes to treat or prevent disease. In the future, this technique may allow doctors to treat a disorder by inserting a gene into a patient’s cells instead of using drugs or surgery. Researchers are testing several approaches to gene therapy, including:
  • ·         Replacing a mutated gene that causes disease with a healthy copy of the gene.
  • ·         Inactivating, or “knocking out,” a mutated gene that is functioning improperly.
  • ·         Introducing a new gene into the body to help fight a disease.

Although gene therapy is a promising treatment option for a number of diseases (including inherited disorders, some types of cancer, and certain viral infections), the technique remains risky and is still under study to make sure that it will be safe and effective. Gene therapy is currently being tested only for diseases that have no other cures.



Tuesday, 15 May 2018


Biomaterials play an important role in Therapeutic Delivery like Biocompatible polymeric gene carriers which have been introduced for treating diverse genetic and acquired diseases. The researchers are working on the biomaterial approaches to significantly improve outcomes of gene #therapies for neurodegenerative disorders. The Nanobiomaterial architecture is the basis for fabrication of novel integrated systems involving cells, growth factors, proteins, cytokines, drug molecules, and other biomolecules with the rationale of creating a universal, all-purpose Nano-biomedical device for personalized therapies.



Sunday, 13 May 2018


Biophotonics:

Biophotonics is an emerging multidisciplinary research area, embracing all light-based technologies applied to the life sciences and medicine. Biophotonics is a scientific discipline of remarkable societal importance. For hundreds of years, researchers have utilized light-based systems to explore the biological basics of life.

Diagnostic Biophotonics:
Diagnostic biophotonics is used to detect diseases in their initial stages before actual medical symptoms occur in patients. By using optics, diagnostic biophotonics provides several advantages of sensing and imaging at the molecular level and also collects multidimensional data for evaluation. Technologies based on light are generally contact-free with less effect on integrity of living subjects and, consequently, can easily be applied in situ.

Therapeutic Biophotonics:
Applications of light include treatment of diseases by altering biological processes. Light is used for modifying the cellular functions photochemically and to remove tissues by photomechanical or photothermal process.



Friday, 11 May 2018


Advanced Materials :

Advanced Materials has been bringing you the latest progress in materials science every week for over 25 years. Advanced Materials are at the heart of many technological developments that touch our lives. Electronic materials for communication and information technology, biomaterials for better health care, sensors for intelligent environment, energy materials for renewable energy and environment, light alloys for better transportation.



Thursday, 10 May 2018


Bone Plates :

Biomaterials used in manufacturing bone plates, currently titanium and stainless steel alloys are the most common in production of bone plates. Other biomaterials such as Mg alloys, Ta alloys, SMAs, carbon fiber composites and bioceramics are potentially suitable for bone plates because of their advantages in biocompatibility, bioactivity and biodegradability. However, today either they are not used in bone plates or have limited applications in only some flexible small-size implants. This problem is mainly related to their poor mechanical properties. Additionally, production processes play an effective role.



Wednesday, 9 May 2018


Heart Valve : 

Cardiovascular disease physically damages the heart, resulting in loss of cardiac function. Medications can help alleviate symptoms, but it is more beneficial to treat the root cause by repairing injured tissues, which gives patients better outcomes. Besides heart transplants, cardiac surgeons use a variety of methods for repairing different areas of the heart such as the ventricular septal wall and valves. A multitude of Biomaterials are used in the repair and replacement of impaired heart tissues. These Biomaterials fall into two main categories: synthetic and natural. Synthetic materials used in cardiovascular applications include polymers and metals. Natural materials are derived from biological sources such as human donor or harvested animal tissues. A new class of composite materials has emerged to take advantage of the benefits of the strengths and minimize the weaknesses of both synthetic and natural materials.



Tuesday, 8 May 2018


Contact Lenses: 

Contact lenses can also be used medically for the treatment of certain diseases. In such cases they are called therapeutic or bandage lenses . Contact lenses range from hard to soft. Hard lenses contain mainly poly(methy1 methacrylate) (PMMA) and are impermeable to oxygen. Hard and semirigid lenses permeable to oxygen are made from copolymers of siloxanes and methacrylates. Flexible, oxygen permeable lenses are made of silicones. Soft contact lenses are prepared from polymers that absorb large quantities of water to become hydrogels. The aqueous phase of the hydrogel is oxygen permeable. Hard and soft hydrophobic lenses require a relatively thick tear film between their posterior surface and the cornea of the eye.


Monday, 7 May 2018


Stem cells are the foundation for every organ and tissue in your body. There are many different types of stem cells that come from different places in the body or are formed at different times in our lives. These include embryonic stem cells that exist only at the earliest stages of development and various types of tissue-specific (or adult) stem cells that appear during fetal development and remain in our bodies throughout life.

All stem cells can self-renew (make copies of themselves) and differentiate (develop into more specialized cells). Beyond these two critical abilities, though, stem cells vary widely in what they can and cannot do and in the circumstances under which they can and cannot do certain things.

Doctors and scientists are excited about stem cells because they could help in many different areas of health and medical research. Studying stem cells may help explain how serious conditions such as birth defects and cancer come about. Stem cells may one day be used to make cells and tissues for therapy of many diseases. Examples include Parkinson’s disease, Alzheimer’s disease, spinal cord injury, heart disease, diabetes, and arthritis.



Friday, 4 May 2018


Biomaterials & its Applications:

Biomaterials is the discipline dealing with natural and synthetic materials as well as the interactions between materials and biological tissues. It covers a wide range of research areas including basic materials science, biocompatibility, implant device development, surgical applications, and failure analysis and has application throughout most physiologic systems (hip and knee implants, contact lenses, coronary artery stents, catheters, etc.)

But the characteristics of biomaterials have evolved over the field’s 50-plus years of existence. In the early days, biomaterials were expected to be inert, or at least biocompatible, to disturb the body as little as possible. The field has since shifted toward developing materials that interact with biological systems in a purposeful way.

Thursday, 3 May 2018


Inflammation in Bone Tissue Regeneration:

Delayed healing or nonhealing of bone is an important clinical concern. Although bone, one of the two tissues with scar-free healing capacity, heals in most cases, healing is delayed in more than 10% of clinical cases. Treatment of such delayed healing condition is often painful, risky, time consuming, and expensive. Tissue healing is a multistage regenerative process involving complex and well-orchestrated steps, which are initiated in response to injury. At best, these steps lead to scar-free tissue formation. At the onset of healing, during the inflammatory phase, stationary and attracted macrophages and other immune cells at the fracture site release cytokines in response to injury. This initial reaction to injury is followed by the recruitment, proliferation, and differentiation of mesenchymal stromal cells, synthesis of extracellular matrix proteins, angiogenesis, and finally tissue remodeling. Failure to heal is often associated with poor revascularization. Since blood vessels mediate the transport of circulating cells, oxygen, nutrients, and waste products, they appear essential for successful healing. The strategy of endogenous regeneration in a tissue such as bone is interesting to analyze since it may represent a successful tissue formation.