The effect of inadequate drying of blood spots on newborn screening analyte concentrations.
Author(s): Moat SJ, Levi M, Birch M, Worlock N, Sundas C, Woodcock L, Kay J, de Souza S, Rodham A
Publication: Ann Clin Biochem, 2025, Vol. , Page 45632251337608
PubMed ID: 40220017 PubMed Review Paper? No
Purpose of Paper
This paper compared levels of amino acids, thyroid-stimulating hormone, immunoreactive trypsinogen and decanoyl-carnitine in air-dried blood spots (DBS) and matched blood spots that were inadequately dried due to storage in a glassine envelope between the pages of a book or in a plastic bag.
Conclusion of Paper
Levels of all analytes were significantly lower in improperly dried (crinkled) blood spots compared to those of air-dried specimens. Compared to air-dried DBS, analyte levels were on average 5-28% lower in specimens placed in a glassine envelope between pages of a book and 28-60% lower in specimens placed in a sealed plastic bag. Importantly, the differences were significant for every analyte in both volunteers after storage in either the sealed plastic bag or in a glassine envelope between the pages of a book. The authors also report that the inter-volunteer variability was low and the inter-assay coefficient of variance was <8% for all analytes.
Studies
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Study Purpose
This study compared levels of amino acids, thyroid-stimulating hormone (TSH), immunoreactive trypsinogen (IRT) and decanoyl-carnitine in air-dried blood spots (DBS) and matched blood spots that were inadequately dried due to storage in a glassine envelope between the pages of a book or in a plastic bag. Lithium heparin blood was collected from two adult volunteers and spiked with phenylalanine, tyrosine, methionine, leucine, isovaleryl-carnitine, glutaryl-carnitine, octanoyl-carnitine, thyroid-stimulating hormone, immunoreactive trypsinogen and decanoyl-carnitine to achieve pathophysiological levels. Blood (40 μL) was spotted using a Revvity-226 devices. Matched blood spots were allowed to air-dry normally at room temp or were improperly dried by being placed in a glassine envelope between pages of a book or by being placed in a sealed plastic bag. All specimens were stored at room temperature for 48 h at room temperature before analysis. TSH and IRT were quantified in 3.2 mm diameter punches using AutoDELFIA Fluoroimmunoassay Kits. Amino acids and acylcarnines were extracted from 3.2 mm diameter punches using methanol and quantified by an in-house electrospray ionization tandem mass spectrometry method.
Summary of Findings:
Levels of all analytes were significantly lower in improperly dried (crinkled) blood spots compared to those of air-dried specimens. Compared to air-dried DBS, analyte levels were on average 5-28% lower in specimens placed in a glassine envelope between pages of a book and 28-60% lower in specimens placed in a sealed plastic bag. Importantly, the differences were significant for every analyte in both volunteers after storage in either the sealed plastic bag or in a glassine envelope between the pages of a book. The authors also report that the inter-volunteer variability was low and the inter-assay coefficient of variance was <8% for all analytes.
Biospecimens
Preservative Types
- Other Preservative
Diagnoses:
- Normal
Platform:
Analyte Technology Platform Small molecule ESI MS Glycoprotein Clinical chemistry/auto analyzer Protein Clinical chemistry/auto analyzer Pre-analytical Factors:
Classification Pre-analytical Factor Value(s) Biospecimen Preservation Conditions during fixation/preservation Air-dried at room temperature
Placed in a glassine envelope between pages of a book
Placed in a sealed plastic bag