Immunoassay

     The tight binding afforded by antibodies for their corresponding antigens enabled the development of many immunoassay formats to generate a signal from minute amounts of target analyte in a sample.

     Immunoassays derive their unique specificity, sensitivity, and flexibility from three important properties of antibodies:

Their ability to bind to an extremely wide range of natural and man-made chemicals, biomolecules, cells, and viruses.

Exceptional specificity for the substance to which each antibody binds.

The strength of the binding between an antibody and its target.

blood gas analyzer

     Most point-of-care blood gas analyzer utilizes electrochemical or optical based detectors to provide fast, affordable, and reliable test results within 30 min.  They are widely used in the emergency department, ICU, operating room, cauterization lab, laboratory, and physician’s office.

The testing menu generally includes:

  • Electrolytes: Na+, K+, Cl-, Ca2+
  • Metabolites: glucose, lactate
  • Blood gas: pH, pO2, pCO2
  • CO-oximetry

ion-selective electrode

     Ion-selective electrode (ISE) are readily miniaturized, highly portable, relatively simple to operate and can provide accurate measurements of ion concentrations with low cost and low energy consumption instrumentation.

     There are three major types of ISEs depending on the ion-selective membrane material employed to fabricate the device: glass membranes (pH meter, sodium electrode), crystalline membranes (LaF3 crystal), and organic polymer membranes. The third type membranes are the most widely used ISE. They generally contain a lipophilic ion-exchanger species and/or an iononophore (ion-carrier) with specific binding affinity to the target ion. 

 

nitirc oxide delivery system

     Nitric oxide (NO) is the smallest biological messenger in the human body.  It functions as a vasodilator, an inhibitor of platelet adhesion and activation, an antimicrobial mediator and a neurotransimitter.  Endothelial cells that line the inner surfaces of all blood vessels produces NO locally.  The emission of NO at the blood/surface interface is critically important since it prevents platelet activation and adhesion to this highly thromboresistant surface.

     Therefore, synthetic polymer materials that can mimic the nature of endothelial cells to release localized NO will enable the preparation of potentially thrombus resistant and bactericidal surfaces.  By immobilizing NO release/delivery coatings onto clinically relevant blood-contacting and implantable medical devices (i.e., vascular grafts, intravascular catheters and sensors, extracorporeal blood-loop, oxygenator etc), the risk of thrombus formation and inflammation/infection can be reduced, and ultimately the in vivo performance and life-time of such devices can be improved. 

general electrochemical sensor

     The use of electrochemical techniques, in which the potential, current, or charge in an electrochemical cell serves as the signal for analytical methods has been widely explored. 

     Electrochemical sensors are advantageous in measurement science, including environmental analysis and clinical diagnosis, due to various inherent properties.  For example, they are relatively inexpensive, capable of real-time monitoring, and are easy to miniaturized and ultimately be implanted to facilitate in vivo tests without complex sample preparations.