Scanning drop sensor

Inventors

Jin, Jian • Xiang, Chengxiang • Gregoire, John M. • Shinde, Aniketa A. • Guevarra, Dan W. • Jones, Ryan J. • Marcin, Martin R. • Mitrovic, Slobodan

Assignees

California Institute of Technology • Lawrence Berkeley National Laboratory • University of California San Diego UCSD

Abstract

Electrochemical or electrochemical and photochemical experiments are performed on a collection of samples by suspending a drop of electrolyte solution between an electrochemical experiment probe and one of the samples that serves as a test sample. During the electrochemical experiment, the electrolyte solution is added to the drop and an output solution is removed from the drop. The probe and collection of samples can be moved relative to one another so the probe can be scanned across the samples.

Core Innovation

The invention provides a system and method for performing electrochemical or electrochemical and photochemical experiments on a collection of samples by suspending a drop of electrolyte solution between an electrochemical experiment probe and a test sample. During the experiment, electrolyte solution is continuously added to the drop while output solution is concurrently removed, maintaining a replenished small volume drop that serves as the electrochemical environment between the probe and sample. The probe and samples can be moved relative to one another to scan across the samples without requiring direct contact, preserving the drop and enabling rapid sequential testing.

The system includes fluid conduits integrated into the probe that add electrolyte solution and remove output solution to refresh the drop. The working electrode is defined at the drop-sample interface, with a reference electrode contacting the drop and a counter electrode positioned within the fluid conduits. This configuration reduces resistance between electrodes, removes reaction products and bubbles by continuous flow, and avoids contamination while allowing optical access to the sample for synchronized electrochemical-optical measurements, including photoelectrochemical experiments.

This setup supports sub-microliter drop volumes and uses electronics to control fluid flow rates and experiment parameters, enabling scanning across large sample arrays. The drop volume remains stable even while the probe or sample collection move laterally to access multiple samples rapidly, ensuring at least one full drop volume refresh between samples and mitigating cross-contamination. Optical collection devices aligned beneath the sample allow in situ, operando characterization of optical properties during electrochemical experiments.

Claims Coverage

The patent includes one independent claim that defines a system for performing electrochemical experiments with integrated fluidic and optical components.

These features collectively define a system that enables controlled fluid management of a microvolumed electrolyte drop for electrochemical measurements combined with synchronous optical detection, and the capacity to scan across multiple samples by moving the probe or sample collection.

Stated Advantages

Documented Applications