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The continuous monitoring of proteins is a current challenge in medical diagnostics. A new electrochemical approach aiming to address this has been described. The method uses antibodies as a recognition element to achieve the real-time measurement of proteins in saliva in the mouth.

Brewing science is an interdisciplinary course taught at many universities in both lecture- and lab-based modalities. The laboratory component of this class typically focuses on the brewing process from malted barley to beer. However, this ignores the malting process--an essential step in making beer, although one typically performed by maltsters outside of the brewhouse. In this report we discuss the development of a malting lab that is suitable to incorporate into introductory brewing science courses in order to help students demonstrate and explain the key process of converting raw barley into malt. During this week-long experiment, students start with raw barley (commercially available in scales that work for all course sizes) and, using small scale and inexpensive custom-made equipment, malt the barley at home for later use in the course. This experiment is suitable for hybrid course laboratories in student homes and apartments with minimal course expenses or requirements and can be implemented in any brewing science course--even those that are predominantly lecture-based.

We describe in detail a new electrochemical DNA (E-DNA) sensing platform based on target-induced conformation changes in an electrode-bound DNA pseudoknot. The pseudoknot, a DNA structure containing two stem-loops in which the first stem's loop forms part of the second stem, is modified with a methylene blue redox tag at its 3' terminus and covalently attached to a gold electrode via the 5' terminus. In the absence of a target, the structure of the pseudoknot probe minimizes collisions between the redox tag and the electrode, thus reducing faradaic current. Target binding disrupts the pseudoknot structure, liberating a flexible, single-stranded element that can strike the electrode and efficiently transfer electrons. In this article we report further characterization and optimization of this new E-DNA architecture. We find that optimal signaling is obtained at an intermediate probe density (~1.8 x [10.sup.13] molecules/[cm.sup.2] apparent density), which presumably represents a balance between steric and electrostatic blocking at high probe densities and increased background currents arising from transfer from the pseudoknot probe at lower densities. We also find that optimal 3' stem length, which appears to be 7 base pairs, represents a balance between pseudoknot structural stability and target affinity. Finally, a 3' loop comprised of poly(A) exhibits better mismatch discrimination than the equivalent poly(T) loop, but at the cost of decreased gain. Optimization over this parameter space significantly improves the signaling of the pseudoknot-based E-DNA architecture, leading to the ability to sensitively and specifically detect DNA targets even when challenged in complex, multicomponent samples such as blood serum.

Abstract: Water-covered lands comprise approximately 30% of the total area of the world's boreal forest biome. Most of these lands are peatlands (i.e., bogs and fens), which store over half [...]

A general, sensitive, and selective approach is demonstrated for the detection of macromolecules that bind to specific small molecule recognition elements. The scaffold is optimized by using a biotin recognition element and streptavidin as a target to obtain the variables defining sensor performance before applying the approach to the detection of anti-digoxigenin antibodies by using the steroid as the recognition element.

A novel approach is described for monitoring the presence of polypeptide-binding targets by fabricating and characterizing excimer-based peptide beacons (PBs) directed against an anti-HIV antibody and the retroviral TAR RNA element. The synthesis of excimer-based PBs needs only a single synthetic step from commercially available modified pyrenes and this approach is well suited for routine laboratory applications.