RT Journal Article SR Electronic T1 Optimizing accuracy and depth of protein quantification in experiments using isobaric carriers JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.08.24.264994 DO 10.1101/2020.08.24.264994 A1 Harrison Specht A1 Nikolai Slavov YR 2020 UL http://biorxiv.org/content/early/2020/10/21/2020.08.24.264994.abstract AB The isobaric carrier approach, which combines small isobarically-labeled samples with a larger isobarically-labeled carrier sample, is finding diverse applications in ultrasensitive mass-spectrometry analysis of very small samples, such as single cells. To enhance the growing use of isobaric carriers, we characterized the trade-offs of using isobaric carriers in controlled experiments with complex human proteomes. The data indicate that isobaric carriers directly enhances peptide sequence identification without simultaneously increasing the number of protein copies sampled from small samples. The results also indicate strategies for optimizing the amount of isobaric carrier and analytical parameters, such as ion accumulation time, for different priorities such as improved quantification or increased number of identified proteins. Balancing these trade-offs enables adapting isobaric carrier experiments to different applications, such as quantifying proteins from limited biopsies or organoids, building single-cell atlases, or modeling protein networks in single cells. In all cases, the reliability of protein quantification should be estimated and incorporated in all subsequent analysis. We expect that these guidelines will aid in explicit incorporation of the characterized trade-offs in experimental designs and transparent error propagation in data analysis.Competing Interest StatementThe authors have declared no competing interest.