Fiber-Based Diagnostics

Integrated fiber Optic Sensor Umbilical Catheter for Blood Gas Monitoring

Intermittent monitoring of blood gases in infants yields only a spot check of the physio-pathological status of the patient, and the results are often delayed. Continuous and non-invasive monitoring is preferred, but current modalities have significant limitations. To address this need, we are developing an integrated fiber optic sensor umbilical catheter for blood gas monitoring in neonates that exploits routinely performed umbilical artery catheterization – the standard of care for sick neonates. Distributed sensors integrated in the wall of the catheter will collect continuous data on blood gases (PaO2, PaCO2, pH, temperature, and bicarbonate) over its entire length without the need to draw blood.

Biopsy Optical Sensor for in situ Tissue Analysis

Current methods for guiding cancer biopsies rely almost exclusively on X-ray, ultrasonic, or magnetic-resonance images. While these methods are far more accurate than the age-old technique of palpation, all three still essentially characterize suspected lesions based only on tissue density. IOS proposes to integrate chemically-sensitive optrodes into the biopsy needle, leaving the main channel clear for unimpeded trocar passage and aspiration, while providing the physician with real-time information on tissue viability and metabolic state by monitoring chemical changes in and around suspected tumors instantaneously during the procedure. This will precisely guide collection of samples suitable for molecular biomarker profiling. In Phase I, we will fabricate a three-sensor demonstration system that will accurately record target chemical concentrations in laboratory tests.

Multianalyte Nanoprobe for Neurochemicals

In cellular and extracellular studies of individual neurons and neural networks, it is imperative to monitor both electrophysiological and neurochemical activity. Electrochemical probes have now been fabricated at a size scale appropriate for such studies, but many neurotransmitters cannot be detected electrochemically. Furthermore, chemically-sensitive electrodes often consume their target analytes; at the sub-micron size scales of interest, this can lead to significant perturbation of the system being studied. Intelligent Optical Systems is working with the University of California Los Angeles to create a new tool for cell-level studies of neurochemistry – a probe that can measure the concentrations of multiple analytes in sub-micron volumes. In this sensor, a multi-channel optical waveguide structure, tapered to a size smaller than the wavelengths of light traveling through it, will be functionalized with fluorescent indicators that react reversibly with target substances. This unique probe will continuously monitor localized neurochemical concentrations on a time scale of milliseconds.