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By combining DNA nanotechnology and high-bandwidth single-molecule detection in nanopipets, we demonstrate an electric, label-free hybridization sensor for short DNA sequences (<100 nucleotides). Such short fragments are known to occur as circulating cell-free DNA in various bodily fluids, such as blood plasma and saliva, and have been identified as disease markers for cancer and infectious diseases. To this end, we use as a model system an 88-mer target from the RV1910cgene in Mycobacterium tuberculosis, which is associated with antibiotic (isoniazid) resistance in TB. Upon binding to short probes attached to long carrier DNA, we show that resistive-pulse sensing in nanopipets is capable of identifying rather subtle structural differences, such as the hybridization state of the probes, in a statistically robust manner. With significant potential toward multiplexing and high-throughput analysis, our study points toward a new, single-molecule DNA-assay technology that is fast, easy to use, and compatible with point-of-care environments.

Minimally invasive techniques enable diagnostics and surgery to be performed through a small incision. This greatly reduces the damage to healthy tissue leading to faster recovery times for the patient. However, the surgeon is deprived of the sensory feedback available with normal surgical techniques. Miniaturised sensors can provide this information about location, diagnostics and the treatment. This application severely limits the size of the device, with some catheters being less than 1 mm in diameter. Catheters are usually defined in multiples of 1/3 mm or 1 french. Further important issues are bio-compatibility, safety and the ability of the sensor to withstand the working environment. Sensors able to meet these demands are improving the efficiency of operations and are opening new opportunities for minimally invasive techniques.

Opioids delivered to the pons inhibit REM sleep, whereas pontine administration of adenosine enhances REM sleep. In other brain areas opioids and adenosine interact to produce antinociception. Adenosine A1 receptors and mu opioid receptors each activate Gi/Go proteins. This study tested the hypothesis that combined treatment with the adenosine A1 receptor agonist SPA and the mu opioid agonist DAMGO would enhance G protein activation to a greater level than produced by either agonist alone. G protein activation was quantified in seven brainstem regions regulating sleep and nociception. This study also tested the hypothesis that G protein activation caused by SPA would be concentration dependent and blocked by the adenosine A1 receptor antagonist DPCPX.

Often in medical applications a single measurement does not give sufficient information to the clinicians. IC technology allows the combination of several sensors in a small volume for instantaneous multi-measurements at a single location. This paper presents two multi-parameter sensors for catheter applications, with initial experimental results, along with the packaging issue - an important aspect for biomedical sensors.