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bioRxiv · 10.1101/2025.11.07.687299

A microvolume method for measuring catalase activity

Rocha, B. C.·Rosa, M. T.·Rocha, J. B. T.·Loreto, E. L. S.
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Abstract

We have developed and validated an innovative protocol for analyzing catalase activity in microvolumes using the NanoDrop spectrophotometer. This method offers a solution to the challenge of working with limited biological samples and provides an efficient alternative to conventional protocols that require larger sample volumes. Unlike typical microplate assays that aim to increase throughput or reduce costs, our protocol was developed specifically for scenarios where biological material is scarce, such as studies with small organisms like Panagrellus redivivus and Caenorhabditis elegans, as well as with certain tissues of Drosophila and other small organisms. A key advantage of the method described here is the ability to accurately measure catalase activity with as little as 2 L of sample, making it ideal for studies where sample availability is extremely limited. The results show that the protocol effectively assesses catalase efficiency and reflects the physiological and metabolic properties of the tissues studied. Inhibitors and denaturants were used to ensure specificity of catalase measurements and the method was optimized for minimal reagent consumption. This approach greatly expands the research possibilities on enzymatic activity in reduced biological models, especially in contexts where small samples are critical, such as limited tissue collections or small organisms Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=140 SRC="FIGDIR/small/687299v1_ufig1.gif" ALT="Figure 1"> View larger version (46K): org.highwire.dtl.DTLVardef@9334fborg.highwire.dtl.DTLVardef@7b66baorg.highwire.dtl.DTLVardef@1957c28org.highwire.dtl.DTLVardef@10a44a7_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Rocha, B. C., Rosa, M. T., Rocha, J. B. T., Loreto, E. L. S.. 2025-11-09. A microvolume method for measuring catalase activity. https://doi.org/10.1101/2025.11.07.687299

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