Calcium Polyphosphate-Based Biomaterials
Calcium Polyphosphate Glass Biomaterials for Medical Applications
Tech Area / Field
- MAT-SYN/Materials Synthesis and Processing/Materials
3 Approved without Funding
Institute of Chemical Sciences, Kazakstan, Almaty
- Kazakh Scientific Center for Quarantine and Zoonotic Diseases, Kazakstan, Almaty
- New York University / Department of Biomaterials and Biomimetics, USA, New York
Project summaryMain purpose of the project is development of new calcium polyphosphate glass (CPPG) materials in the forms of fibers, spheres, and porous particles or blocks for bone repair and tissue engineering.
State of the art in the field and the impact of the proposed project on the progress in this field
The bone diseases of humans spread progressively around the world. The latest estimation showed that about 25 millions of people in the USA suffer from bone diseases. The share of Kazakhstan's population, which is subjected to bone diseases and particularly to dental diseases is much more. The problem is especially serious for ecologically adverse regions of the country.
Calcium phosphates are widely used as restorative and substitution materials in dentistry, orthopedics and surgery because calcium phosphate salt hydroxyapatite (HA) is the main mineral of the human’s bones and teeth. The most popular for medicine becomes the calcium phosphate bioceramics. Tricalcium phosphate is often used for producing of such kinds of materials. Recently a series of new sorts of bioceramics was created. They contain the crystalline calcium polyphosphate fiber. However, the most wide spread materials are that containing hydroxyapatite. Unfortunately, manufacturing of HA ceramics is connected with a lot of technical problems. First of all, to produce a good material it needs application of high temperatures up to 1300-14000С. Besides, rather low strength and hardness are typical characteristics for the ceramics on the basis of apatite or tricalcium phosphate. Perhaps, this is a main reason why process of searching of new inorganic biomaterials on the basis of calcium phosphates continues. A possible way for increase of the strength of biomaterials is the reinforcing of them by calcium polyphosphate glass fibers or glass micro-spheres. The serious interest represents the porous calcium polyphosphate glass as well. All the three types of glass materials can be used as armature in combination with the newest phosphate cements. In the certain measure such materials are capable to replace ceramics.
The expected scientific data can be used for development of technology for producing of new materials for medicine. The data concerning the nature of (CPPG) materials and their formation mechanism have a fundamental theoretical meaning. The results of microbiological investigations will make more broadly the conception of interaction of calcium phosphate materials with living tissues - cells and microbes. Created materials can be applied in medicine, particularly in dentistry, orthopedic, and possible in the surgery.
Competence of the project participants in the area of proposed investigations
The team of scientists from ICS has the large experience in area of phosphate chemistry and particularly of calcium phosphate materials and glass like phosphates. The greatest experience in the area of calcium phosphate biomaterials has collaborator and her group – NYU. Conversion organization KSCQZD is well known institute of microbiological profile. Two teams of scientists from this center together with ICS perform successfully the works connected with investigations of different cultures of microbes on phosphate substrates. These works are performed at financial support of the ISTC.
Expected results and their application
As a result of the given work will be new scientific knowledge about nature and properties of the CPPG materials synthesized including biocompatibility and bioactivity, about relations of the CPPG materials with microbes and living tissues of the cultural and animal models. New methods for production of CPPG materials in the form of fibers, spheres and porous blocks will be developed and patented. Conclusion will be done about potential medical use of CPPG materials in bone repair and tissue engineering (Pilot study).
Accordance to the objectives of ISTC
The project serves to the basic purposes of the ISTC because its tasks are:
- Involving of scientists that were connected before with development of the weapon of mass defeat to civil area - development of materials intended for treatment of the people’s deceases.
- Collaboration of independent groups of the researchers from Kazakhstan with the foreign partners.
- Exchange of experience and knowledge between of chemists and former developers of biological weapon.
- Material support of useful scientific researches directed on the fulfillment of the important problem, connected with treatment of bone diseases of the human.
- Acquaintance to the modern market attitudes (relations), because the practical realization of the future mini-technologies will open a perfect way for familiarizing of the scientists with commercial and market activity.
Outline scope of activities
Two main groups of scientists will do the job. They are chemists, specialists in area of material chemistry, microbiologists, immunologists and physicians. The number of participants is 22. General labor inputs of the project are 7,706 person-days.
Role of the foreign collaborator assumes the following:
- Exchange by scientific and technical information.
- Providing of comments to the technical annual and final reports.
- Correction of the direction of researches and schedule.
- Investigation in vitro of the biocompatibility and bioactivity of CPPG materials using cell culture models (this work will be performed by collaborator).
- Joined experiment– investigation of the micro-structure of CPPG materials with using of equipment of the collaborator (SEM).
- Joined scientific publications and patenting (two or three patents).
- Conduction of two joint seminars.
Technical approach and methodology
For producing of calcium phosphate glass materials will be developed techniques based on a rapid cooling of the melted phosphates in a controlled condition. Previously the compositions of the melted phosphates and glasses will be determined, which would be able to provide the formation of the CPPG materials without crystallization during the repeated heating. To receive the fibers with controlled measurements (length and diameter) will be used the melts with necessary viscosity at strongly determined temperature. Some addition components will be entered into the main phosphate to regulate the properties of the melts. For producing of glass spheres will be used technique of rapid cooling of small glass particles in liquids or in air streams. Porous materials will be synthesized via thermal treatment of glass fibers or particles at strongly determined temperature and at regime of cooling. For investigation of received materials will be used thermal analysis, IR, Raman, and UV/VIS spectroscopy, microscopy,
31P NMR spectroscopy, X-ray diffraction, scanning electron microscopy and others. The solubility and some mechanical properties of the materials will be investigated too. Biomedical tests will be performed according to known methods with using of cell culture models, some bacteria cultures and laboratory animals as well. The techniques of Passiv Hemagglutination tests, Elisa-test and so on will be applied for the study of the properties of vaccines Y.pestis and F.tularensis produced with the help of CPPG materials.
The International Science and Technology Center (ISTC) is an intergovernmental organization connecting scientists from Kazakhstan, Armenia, Tajikistan, Kyrgyzstan, and Georgia with their peers and research organizations in the EU, Japan, Republic of Korea, Norway and the United States.
ISTC facilitates international science projects and assists the global scientific and business community to source and engage with CIS and Georgian institutes that develop or possess an excellence of scientific know-how.