Nanomaterials For Your Infrastructure
HomeSite MapContact Us
Inframat Logo Nanostructured agglomerates High frequency soft magnetic core Catalyst Bio-Engineering
Tel: 860.432.3155
email: info@inframat.com
Products Services Sponsored Research About Us News Directions Careers
Headquarters
Nanostructured Materials
Thermal Spray Powders
SOFC Materials
Zirconia Grinding Media
Materials & Chemicals
Magnetic (Nano) Powders
Cored Wire Feedstock
Molybdenum and Tungsten Rod
Solution Plasma Spray Equipment
 
Functionalized Nanoparticle Based Biosensors

Inframat is in the process of developing two types of nanostructured biosensors, including nanoparticle based glucose sensors for diabetes application, and bioconjugated nanoparticle based biosensors for neurotransmitter detection applications.

Nanoparticle based glucose sensor: A particularly common problem associated with glucose biosensors has been protein deposition and fibrous encapsulation known as biofouling limiting device lifetime. Protein deposition on biosensor membrane surfaces, a significant cause of biofouling, has been detrimental to biosensor performance. While this problem primarily affects long-term implants (more than 4 weeks), short-term implant (3-7 days) performance is impaired as well. A serious need exists for biocompatible membranes that can reduce protein deposition on implantable devices. In addition, the coating layer on a membrane surface is critical for obtaining good membrane properties. However, traditional planar organic coatings, with biocompatible and protein resistant auxiliaries typically added physically, have problems such as incomplete coverage of functional components, insufficient layer thickness, low functional brush density, and difficulty keeping functional components adhered to the surface.

Implantable biosensors can greatly benefit from improving membrane and coating layer structures and properties. This requires the use of a novel coating material on the biomembrane surface that reduces protein adsorption and the subsequent inflammatory response. Inframat’s concept insolving this protein deposition problem is to exploit a novel nanostructured membrane for implantable glucose sensor applications, which composes of an optimized biocompatible membrane template coated with protein resistant layers of advanced structures. the nanostructured membrane will control the tissue/glucose sensor interface interaction. In Phase I, we will prepare a protein-resistant nanostructured membrane, evaluate its physical properties, and confirm the improved functional performance in glucose sensor applications. Technological innovations of this nano-approach include:

(1). A semi-permeable membrane template with optimized & physiologically compatible structures for precise control of molecular diffusion and interphase interaction
(2). A nanostructured coating system composed of silica (“SiO2”) nanoparticle cores and high density functional polymer brushes, chemically grown from the silica nanoparticle cores, resisting protein adsorption and improving coverage and binding ability of the functional components
(3). An integrated membrane template/coating system for protein deposition prevention and the subsequent tissue response minimization
(4). A composite membrane with the requisite transport properties for oxygen & glucose

There has been little effort reported until now in developing a coating system to optimize membrane surface structure and to enhance the biocompatibility of implantable device. Most of the work is concentrated on the optimization of the membrane itself. Actually, the membrane surface plays a very important role because it directly contacts the body. Inframat’s design is a novel and new protein-resistant and biocompatible surface coating system. A schematic diagram illustrating the relationship between the membrane template and nanoparticle coating system with polymer brushes is shown in Fig. 1.

Membrane coated with polymer brush nanoparticle coating system to control protein adsorption

Besides the glucose sensor applications, this nanostructured membrane system can be used for a variety of implantable devices such as stents, hip, and knee implants, as well as biosensors. The response of current implantable biosensors, particularly glucose sensors, is influenced by protein adsorption and biofouling. This coating system will greatly reduce protein adsorption and increase biocompatibility for glucose sensors, stents, and other implantable devices thereby extending the lifetime of these devices. Anticipated socio-economic benefits will be improved commercial competitiveness, lower overall health costs, and improved quality of life.

Nanoparticle based neurotransmitter sensors: Gamma-aminobutyric acid (“GABA”) is a main mammalian nervous system inhibitory neurotransmitter, playing important roles in neural function and dysfunction. Accurate real time measurement of GABA will greatly accelerate discoveries on the key role of GABA in motor disorders including Huntington’s disease and Parkinson’s, seizures, myoclonic discharges, and alcohol addiction. Accurate assessment of changes in its extracelluar content on-line, in relatively short time-spans, would lead to a better understanding of its functions. GABA is insensitive to ultra-violet (UV)-visible spectroscopic determination methods. Current technologies for extracellular measurement of GABA focus on microdialysis of the cerebro-spinal fluid, followed by liquid chromatography combined with pre-/post column derivatization. Liquid chromatography-based measurements are not continuous, while microdialysis itself is an invasive procedure that causes neuronal death and reactive gliosis and has very poor spatio-temporal resolution. Also, direct electrochemical monitoring of extracellular GABA in the brain is very difficult because a specific active enzyme capable of generating a redox species does not exist for GABA.

Inframat is currently exploring novel functionalized biomaterials to dramatically improve biosensor response in high sensitivity detection for neurotransmitter applications, via a “competitive enzyme immunoassay” strategy, to electrochemically measure non-electroactive GABA neurotransmitter concentrations. This technology (1) adopt IMC’s economically viable wet chemical synthesis technique to produce antibody-linked biocompatible nanomaterials, (2) immobilize functionalized nanoparticles onto transducers to produce high sensitivity biosensors for real time monitoring of GABA concentrations in a PBS buffered solution, and (3) enable in-vitro testing of the biosensor based functionalized nanoparticles in artificial cerebro-spinal fluid (CSF). This is the first time that an antibody-conjugated nanoparticle based approach is being attempted for GABA determination. This approach will enable biosensors continuous and direct measurement of GABA concentrations, and can also be extended to multiple channels to obtain a spatial-temporal distribution in a brain slice and cell culture preparations. The development of this selective, sensitive, and rapidly responding GABA electrochemical immunomicroprobe will make it possible to measure dynamic events associated with GABA neurotranmission in the central nervous system, and the establishment of a GABA microprobe capability to monitor the component of the basal extracellular GABA level derived from brain tissue neuronal activities.

 


Tel: 860.432.3155 | Fax: 860.432.3722 | info@inframat.com

Products | Services | Sponsored Research | SPS Equipment

Home | About Us | News | Directions | Contact Us | Site Map | Careers