Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
A number of scientific methods have been developed to detect and/or measure one or more analytes in a person's blood. The presence or absence of a physiologically relevant analyte in the blood, or the presence at a particular concentration or range of concentrations, may be indicative of a medical condition or the person's state of health. Physiologically relevant analytes may include enzymes, hormones, proteins, cells, electrolytes, saccharides, fatty acids, triglycerides, or other molecules.
In a typical scenario, a person's blood is drawn and sent to a lab where a variety of tests are performed to measure various analyte levels and parameters in the blood. The variety of tests may be referred to as “blood work,” where the blood is tested for the presence of various diseases, or analyte levels such as cholesterol levels, etc. For most people, the blood tests are infrequent, and an abnormal analyte level indicative of a medical condition may not be identified for some time after the blood work is performed. Thus, the continuous or semi-continuous monitoring of analyte levels is desirable.
Physiologically relevant analytes may also be present in a person's sweat and/or interstitial fluid. These analytes include sugars, salts, fatty acids, amino acids, coenzymes, hormones, neurotransmitters, and cell waste products. Nanotechnology platforms have found many applications in life sciences, but the requirement that nanoparticles to remain immobilized at the point of injection/implantation has been hindered by rapid clearance through several pathways, including immune cell internalization, interstitial fluid flow, tissue remodeling, and Brownian motion.
For example, applications in which a nanoparticle must reside in a static environment such as articulating joints, skin, bone, and eyes still means that phagocytic cells and proteins in the environment will easily interact with the nanoparticles and interfere with their long-term function.