Toward an Injectable Continuous Osmotic Glucose Sensor

Abstract

Current studies have demonstrated the design, layout, and performance of a prototype osmotic sensor in vitro using an affinity assay solution for up to four weeks. The small physical size conforms to an injectable device, forming the basis of a conceptual monitor that offers a tight glycemic control of BG.

Fabrication and Testing of an Osmotic Pressure Sensor for Glucose Sensing Application

“…The interference from other substances needs to be addressed for the improvement of this sensor. The selectivity of this sensor may be improved by employing glucose affinity materials, like hydrogel or Concanavalin (Con) A-dextran [26][27][28], in the device instead of a standard solution. The sensing material employed in [27,28] consists of Con A, which possesses an affinity toward glucose, and the equilibrium is perturbed by glucose binding to lectin, triggering a dissociation of dextran that is proportional to the increase in glucose.…”

“…The selectivity of this sensor may be improved by employing glucose affinity materials, like hydrogel or Concanavalin (Con) A-dextran [26][27][28], in the device instead of a standard solution. The sensing material employed in [27,28] consists of Con A, which possesses an affinity toward glucose, and the equilibrium is perturbed by glucose binding to lectin, triggering a dissociation of dextran that is proportional to the increase in glucose. In addition to Con A-dextran, one needs a special semi-permeable membrane that allows selective diffusion of glucose across the membrane, but that prevents the transport of larger molecules, such as peptides or proteins, or other potentially interfering molecules, such as lactate or polysaccharide, contained in body fluids [36].…”

“…In addition to Con A-dextran, one needs a special semi-permeable membrane that allows selective diffusion of glucose across the membrane, but that prevents the transport of larger molecules, such as peptides or proteins, or other potentially interfering molecules, such as lactate or polysaccharide, contained in body fluids [36]. Generally, cellulose acetate (CA), cellulose ester and polyamide (PA) membranes are used in glucose sensing application based on the osmosis principle [27,28,36,37]. The cellulose membranes present chemical and biological resistances to the body and are not suitable for a long-term implant.…”

“…Another glucose sensor based on volume change due to the flow of water across the semi-permeable membrane has been developed [25]; but, the device is large in size, and its accuracy can be improved. In another approach, smart hydrogels are confined inside a pressure sensor to facilitate the measurement of the change in glucose concentration levels [26][27][28]. Though its response time is high, the inclusion of smart hydrogels offers high sensitivity and selectivity.…”

Thin film nanoporous electrodes for the selective catalysis of oxygen in abiotically catalysed micro glucose fuel cells

“…Current applications extend to implantable neuroprosthetic devices [2] such as cochlear implants [3] and neural stimulating electrodes [4][5][6], as well as microfabricated devices targeting temperature, blood pressure, immuno-isolation, drug delivery, and microinjection [7,8]. Still, one critical issue has remained with respect to the power supply since stringent size constraints of the implant have compromised the available space required by batteries.…”