Capacitance‐to‐digital: The upgrades of single chip detector

Abstract

The capacitance-to-digital single chip detector was upgraded. The paper discusses hardware issues and benefits of the designed/upgraded detector. The device can be operated from rechargeable lithium-ion battery as stand-alone, portable system and is capable of transmitting real-time data wirelessly. The detector and additional modules (battery, battery holder, microcontroller board, wireless module) weight is less than 85 g. Electrophoretic separation in low conductivity 20 mM MES/L-His buffer, pH 6.1, was performed in order to evaluate detection parameters. The system is capable of quantification of potassium ions down to 0.31 μM. Investigation of differential signal acquisition configuration showed improved performance regarding external noise and temperature fluctuations. The system can be a solution for stand-alone, field-portable capillary format separation detector.

Cytotoxic attributes of antiviral plants rich in polyphenolic and volatile compounds

“…The CE system had a contactless conductivity detector integrated following the previously published procedures [18,19]. The gas chromatography-mass spectrometry system GC2010 and GCMS-QP2010 (Shimadzu, Japan) was used for the analysis of volatiles.…”

Contactless conductivity detection for analytical techniques— Developments from 2014 to 2016

“…Drevinskas and coworkers as well as Elkin designed detectors based on integrated circuits available from Analog Devices for the high resolution measurements of small capacitance changes (AD7745 and AD7746). These devices are intended for the measurement of signals from sensors, such as for pressure and humidity, and incorporate all the necessary circuitry, including an analog‐to‐digital convertor in a tiny surface mount package.…”

“…But as also Dasgupta has pointed out , this must be due to the fact that the integrated devices are meant to measure isolated capacitors, not circuitries consisting of several components, and thus produces a varying error signal when a changing resistive element is present (see the data sheet for the device). Nevertheless, the approach allows the construction of very compact detectors based on just a single integrated circuit, with good performance .…”

Application of capacitively coupled contactless conductivity as an external detector for zone electrophoresis in poly(dimethylsiloxane) chips

“…In contactless mode , the sample is isolated from the electrodes by a thin nonconducting material avoiding electrode fouling. There are several papers describing miniaturized C 4 D detectors .…”

“…In contactless mode , the sample is isolated from the electrodes by a thin nonconducting material avoiding electrode fouling. There are several papers describing miniaturized C 4 D detectors . The most widely used and commercially available capacitively coupled contactless conductivity detection (C 4 D) systems have a headstage format that can be matched with a fused silica capillary , but recently new C 4 D platforms have been introduced for microchips .…”