Dataset Information

How low is really low? Comparison of two C-peptide assays to establish residual C-peptide production in type 1 diabetes.

ABSTRACT:

Introduction

C-peptide is an important marker to assess residual insulin production in individuals with type 1 diabetes (T1D). The accuracy and detection limits of C-peptide assays are important to detect C-peptide microsecretion and to reliably observe changes over time in these people. We compared and verified two commercially available assays able to measure C-peptide in the picomolar range.

Methods

The ultrasensitive Mercodia enzyme-linked immunosorbent C-peptide assay (ELISA) was compared with the Beckman immunoradiometric assay (IRMA) for C-peptide, assessing reproducibility (coefficient of variation [CV]), limit of blank (LoB), limit of detection (LoD) and limit of quantitation (LoQ).

Results

For both assays within-run and between-run variation were high at the low (around the detection limit) C-peptide concentration range, with CVs of around 40%. LoB values for the ultrasensitive ELISA and the IRMA were 1.3 and 0.16 pmol/L respectively. LoD values were 2.4 and 0.54 pmol/L respectively. LoQ values were 9.7 and 3.8 pmol/L respectively. Only the IRMA met the specifications claimed by the manufacturer.

Conclusions

The IRMA provided the lowest threshold for quantification of serum C-peptide. LoQ of commercially available assays should be established in-house before applying them in research studies and clinical trials in which low C-peptide levels have clinical or scientific relevance.

SUBMITTER: de Leur K

PROVIDER: S-EPMC9303196 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Publications

How low is really low? Comparison of two C-peptide assays to establish residual C-peptide production in type 1 diabetes.

de Leur Kitty K Vollenbrock Charlotte C Dekker Pim P de Vries Martine M Birnie Erwin E Mul Dick D Wolffenbuttel Bruce H R BHR Groen Joost J Aanstoot Henk-Jan HJ Boesten Lianne L

Diabetic medicine : a journal of the British Diabetic Association 20220117 5

<h4>Introduction</h4>C-peptide is an important marker to assess residual insulin production in individuals with type 1 diabetes (T1D). The accuracy and detection limits of C-peptide assays are important to detect C-peptide microsecretion and to reliably observe changes over time in these people. We compared and verified two commercially available assays able to measure C-peptide in the picomolar range.<h4>Methods</h4>The ultrasensitive Mercodia enzyme-linked immunosorbent C-peptide assay (ELISA) ...[more]

PMID: 34989030

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Dataset Information

How low is really low? Comparison of two C-peptide assays to establish residual C-peptide production in type 1 diabetes.

Introduction

Methods

Results

Conclusions

Publications

How low is really low? Comparison of two C-peptide assays to establish residual C-peptide production in type 1 diabetes.

Similar Datasets

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