# New Technologies for detecting extracellular fluxes

> **NIH NIH R01** · UNIV OF MASSACHUSETTS MED SCH WORCESTER · 2022 · $364,205

## Abstract

Abstract:
The goal of this Focused Technology and Development grant is to repurpose intracellular
fluorescent ion and metabolite sensors to detect extracellular fluxes. The three orthogonal
approaches directly target the cell’s glycocalyx: the nanometer thick, sugar‐coating where ion
and metabolite concentrations vary greatly during ion channel and membrane transporter
activity. Aim 1 describes an approach to attach any fluorescent protein sensor to cells
metabolically-labeled with an unnatural azidosugar. Aim 2 is a non-genetic approach that
labels all mammalian cells—including human cells—with both small molecule and protein
fluorescent sensors. Aim 3 is a chemical genetic approach to achieve cell-type-specific labeling
with small molecule and protein fluorescent sensors. Completion of the aims will convert these
working prototypes that utilize three major classes of fluorescent sensors (small molecule,
protein, and FRET) into technologies that enable the visualization of ions and metabolites at the
surface of a primary cells, tissues, and potentially in living animals.

## Key facts

- **NIH application ID:** 10456044
- **Project number:** 5R01GM138697-02
- **Recipient organization:** UNIV OF MASSACHUSETTS MED SCH WORCESTER
- **Principal Investigator:** WILLIAM R KOBERTZ
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $364,205
- **Award type:** 5
- **Project period:** 2021-08-01 → 2025-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10456044

## Citation

> US National Institutes of Health, RePORTER application 10456044, New Technologies for detecting extracellular fluxes (5R01GM138697-02). Retrieved via AI Analytics 2026-05-26 from https://api.ai-analytics.org/grant/nih/10456044. Licensed CC0.

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