Translating Molecular Recognition into a Pressure Signal to enable Rapid,Sensitive, and Portable Biomedical Analysis

Herein, we demonstrate that a very familiar, yet underutilized, physical parameter—gas pressure—can serve as signal readout for highly sensitive bioanalysis. Integration of a catalyzed gas‐generation reaction with a molecular recognition component leads to significant pressure changes, which can be measured with high sensitivity using a low‐cost and portable pressure meter. This new signaling strategy opens up a new way for simple, portable, yet highly sensitive biomedical analysis in a variety of settings.     

Dose‐Dependent Response of Personal Glucose Meters to Nicotinamide Coenzymes: Applications to Point‐of‐Care Diagnostics of Many Non‐Glucose Targets in a Single Step

We report a discovery that personal glucose meters (PGMs) can give a dose‐dependent response to nicotinamide coenzymes, such as the reduced form of nicotinamide adenine dinucleotide (NADH). We have developed methods that take advantage of this discovery to perform one‐step homogeneous assays of many non‐glucose targets that are difficult to recognize by DNAzymes, aptamers, or antibodies, and without the need for conjugation and multiple steps of sample dilution, separation, or fluid manipulation. The methods are based on the target‐induced consumption or production of NADH through cascade enzymatic reactions. Simultaneous monitoring of the glucose and L ‐lactate levels in human plasma from patients with diabetes is demonstrated and the results are comparable to those from current standard test methods. Since a large number of commercially available enzymatic assay kits utilize NADH in their detection, this discovery will allow the transformation of almost all of these clinical lab tests into POC tests that use a PGM.     

Highest Pressure Adsorption Equilibria Data: Measurement with Magnetic Suspension Balance and Analysis with a New Adsorbent/Adsorbate-Volume

Adsorption data at high pressures provide information about properties of the adsorbent material and about the structure of the adsorbed phase. In order to obtain this information adsorption processes need to be measured in a wide pressure range and require careful experimental data handling. In this paper, an experimental installation with a magnetic suspension balance for the gravimetric measurement of adsorption equilibria data at pressures still inaccessible for this experimental technique will be presented. Using this instrument the adsorption data of He, CH₄, N₂ and Ar on a microporous activated carbon are measured at pressures up to 50 MPa at T = 298.15 K. The resulting data allow a critical discussion of the commonly used model for the volume of the adsorbent material (i.e. the Helium-volume). As a result of this, a new model for the volume of the adsorbed phase is proposed. This volume model allows to calculate a pressure dependent density of the adsorbed phase. The model and the resulting densities of the adsorbed phase are discussed concerning their physical sensitivity.