Advances and prospects in glucose assay technology

Abstract

Glucose assay has long been central to therapy of diabetes mellitus. In the spirit of this occasion commemorating the 75th Anniversary of the Discovery of Insulin, we review here some of the important advances in glucose assay methodology, give our opinions on the present status of glucose assay technologies, and speculate on potential advances in the near future. Some aspects of this review have recently been published elsewhere [1]. A brief historyGlucose assays have been central to the treatment of diabetes from the early days of treatment. The discovery of the effect of insulin at the biochemical level was made possible by an early glucose assay based on the chromogenic reduction of a copper solution by glucose [2]. This assay and its successive modifications were not completely specific for glucose in the presence of other reducing sugars and required careful preparation of relatively large samples, but were nevertheless useful for laboratory assay of glucose in blood and urine. In the following years, clinical glucose assay methodology evolved rapidly, incorporating enzymes for specificity, requiring less sample preparation, smaller volumes, and becoming fully automated [2].Qualitative tests for glucose were later developed based on glucose oxidase and reagents impregnated in paper strips. This advance facilitated patient involvement in glucose assay and the approach was used widely for urine glucose determinations because of its convenience, even though the assay was originally considered less reliable than blood assays. In the past decade, this technology has advanced dramatically in conjunction with the development of home glucometer instrumentation, to the point of providing quantitative, convenient and inexpensive blood glucose determination. The evolution of this technology represents a revolutionary improvement in the management of diabetes, as widespread, frequent and quantitative blood glucose testing is now possible, leading to more appropriate insulin administration schedules and closer involvement of the patient in therapy [3]. Desired new featuresThe results of the Diabetes Control and Complications Trial [4] suggest the value of close blood glucose control in reducing the complications of Diabetologia (1997) Summary The evolution of glucose assay methods has been central to the development of present therapies for diabetes mellitus. However, new blood glucose assay capabilities, such as convenient and truly continuous monitoring, are now needed to foster a new era of close blood glucose control. The principles and present status of glucose sensors being developed that may fill these requirements are reviewed here.

Factory-Calibrated Continuous Glucose Sensors: The Science Behind the Technology

“…5 If the sensitivity of the sensor to glucose does not change over the wear time, then recalibrations are not necessary. Alternatively, if the sensor response does change, recalibrations by the user can compensate for that sensor drift.…”

Swelling Properties of Hydrogels Containing Phenylboronic Acids

“…Blood glucose levels in diabetics exhibit large swings throughout the day. However, current widely used devices, such as test strips and glucose meters, give only discrete time information about blood glucose level, possibly missing fluctuations involving sudden increase or decrease in glucose level [3,4]. Recently commercialized enzyme based sensors such as Medtronic CGMS ® Gold TM and Dexcom ® G4 Platinum can offer continuous information, but they can be problematic due to instability of the enzyme, fouling under physiological conditions, and inflammation and infection that result from breaching the skin with a needle electrode [5].…”

Optical properties of hydrogels filled with dispersed nanoparticles

“…Thus, hydrogel samples containing dispersed phase diffuse the electromagnetic emission of the visible spectrum depending on the emission wavelength and amount of dispersed phase according to Eq. (1).…”

“…Polymeric materials with specific stimuli responsive behavior are widely used for medical and biotechnological applications [1][2][3][4]. In particular, polymeric hydrogel systems have attracted great interest due to their soft and flexible consistency and their ability to absorb large amounts of water, keeping at the same time their three-dimensional stability [5,6].…”