System and method for detection of silver

Inventors

Pennathur, Sumita • Crisalli, Peter Joseph • Chiarello, Ronald Phillip

Assignees

University of California, San Diego • Alveo Technologies Inc

Abstract

Embodiments provide silver detection systems and methods for detecting the presence of silver ions in one or more samples. In a detection method, a sample and TPEA2 molecules are introduced into a channel. A first potential difference is applied across the length of the channel in a first direction, and a first electrical property value is detected. Subsequently, a second potential difference is applied across the length of the channel in a second opposite direction, and a second electrical property value is detected. Presence or absence of silver ions in the channel is determined based on a comparison between the first and second electrical property values.

Core Innovation

A silver-ion detection approach uses an elongated micro/nanochannel disposed between a first electrode and a second electrode, where the channel has a length substantially greater than its width. A sensor compound comprising TPEA2 and sodium tetraborate is allowed to flow along the length of the channel, and interaction between silver ions and the sensor composition occurs within the inner space of the channel. The interaction modifies electrical behavior along at least a portion of the channel length, affecting an electrical property measured in the channel.

Detection is based on electrical comparison using a reference electrical property value and a sample channel electrical property value. A measured electrical property value is obtained after introducing the sample and the sensor composition into the channel while a potential difference is applied across the length of the channel, and the measured and reference electrical property values are compared to determine whether silver ions are present. In some variants, the comparison uses electrical-property values obtained under different conditions, including selecting equilibrium values from monitored time periods and applying opposite-direction potentials across the channel length.

The system architecture includes circuits for measurement, equilibration, comparison, and memory/storage of reference values, and can support multi-channel detection configurations. The disclosed sensing rationale relates the observed electrical changes to microfluidic/electrokinetic effects, including the role of an electrical double layer (EDL), and is supported by modeling discussion in connection with Poisson-Boltzmann, Poisson-Nernst-Planck, and Navier-Stokes frameworks.

Claims Coverage

The partial content contains three independent claims. Across these claims, inventive features focus on an elongated electrode channel, flowing a sensor composition comprising TPEA2 and sodium tetraborate, applying potential differences, measuring electrical properties along the channel length, establishing a reference electrical property value, comparing values, and determining presence or absence of silver ions based on the interaction in the channel.

The independent claims define a channel-based silver-ion detection method that relies on flowing a TPEA2 and sodium tetraborate sensor composition through an elongated channel between electrodes, applying potential difference(s), measuring electrical properties along the channel length, establishing a reference electrical property value, and comparing electrical responses to determine whether silver ions are present, including an option to apply opposite-direction potentials for comparative measurement.

Stated Advantages

Documented Applications