Pre-Analytical and Clinical Validation of a Dried Blood Spot Assay for Asymmetric Dimethylarginine and L-Arginine

Asymmetric dimethylarginine (ADMA) inhibits nitric oxide (NO) synthesis. It is a risk marker for cardiovascular events and mortality in patients with cardiometabolic diseases and in population-based studies. Plasma or serum analysis of ADMA may be hampered by pre-analytical sample handling. We validated a dried blood spot (DBS) assay for ADMA and L-arginine and show here that this assay has excellent variabilities and reproducibilities. Filter paper is impregnated with the arginase inhibitor nor-NOHA (Nω-hydroxy-nor-Arginine) to avoid L-arginine degradation. Clinical validation of this DBS assay confirms elevated ADMA concentration in hemodialysis patients as compared to healthy controls, higher ADMA concentrations in men versus women, and elevated L-arginine concentration in subjects supplemented with L-arginine. The DBS assay was used in a cohort study involving 100 primarily healthy subjects in the Andean region to assess the impact of chronic intermittent hypoxia on ADMA and L-arginine; ADMA DBS concentration at sea level was prospectively associated with pulmonary hypertension after six months of exposure to 3500 m. In a cohort of 753 individuals, L-arginine/ADMA ratio significantly decreased with increasing number of traditional cardiovascular risk factors. Analysis of ADMA and L-arginine in DBS is a reliable and reproducible method for quantitation of these markers in field studies.

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Clinical Validation of a Dried Blood Spot Assay for 8 Antihypertensive Drugs and 4 Active Metabolites

Therapeutic Drug Monitoring ◽

10.1097/ftd.0000000000000703 ◽

2020 ◽

Vol 42 (3) ◽

pp. 460-467

Author(s):

Laura E. J. Peeters ◽

Lida Feyz ◽

Edon Hameli ◽

Tom Zwart ◽

Soma Bahmany ◽

...

Keyword(s):

Antihypertensive Drugs ◽

Dried Blood Spot ◽

Clinical Validation ◽

Active Metabolites ◽

Blood Spot

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Candidate reference method for determination of vitamin D from dried blood spot samples

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2019-0397 ◽

2020 ◽

Vol 58 (5) ◽

pp. 817-827 ◽

Cited By ~ 2

Author(s):

Rosita Zakaria ◽

Katrina J. Allen ◽

Jennifer J. Koplin ◽

Peter Roche ◽

Ronda F. Greaves

Keyword(s):

Vitamin D ◽

Internal Standard ◽

Reference Method ◽

Population Level ◽

Population Based ◽

Dried Blood Spot ◽

Coefficient Of Determination ◽

Plasma Vitamin ◽

Blood Spot

AbstractBackgroundThe current millennium has seen an explosion in vitamin D testing with the overarching aim of requests to clinically stratify patients as replete or deficient in vitamin D. At a population level, dried blood spot (DBS) sampling offers a less invasive and more practical application for assessment of vitamin D status. We have therefore aimed to develop a sensitive and robust DBS vitamin D method that is traceable to serum for use in population-based studies.MethodsBlood spots, calibrators and controls were prepared by punching a 3.2 mm DBS from filter paper and placed into a 96-well micro-plate. The DBS disk was eluted with a combination of water-methanol and internal standard (ISTD) solution followed by supported-liquid extraction and derivatisation. The extract was analysed by liquid-chromatography tandem-mass spectrometry in positive electrospray-ionisation mode with 732.5 > 673.4 and 738.4 > 679.4 m/z ion-transitions for derivatised vitamin D and the ISTD, respectively. Vitamin D results were made traceable to the National Institute of Standards and Technology reference material through the inclusion of Chromsystems vitamin D calibrators.Results25-Hydroxy-vitamin D3 and its related ISTD were detected at a retention time of 7 min. The seven-point calibration-curve consistently demonstrated a coefficient of determination of 0.99 with an experimentally determined reportable range of 0.5–376 nmol/L. Method validation studies using DBS samples demonstrated 12.9% between-assay imprecision at 45 nmol/L, 84% average recovery and high correlation with plasma vitamin D (correlation coefficient = 0.86).ConclusionsWe have successfully developed an analytical method for vitamin D quantitation from DBSs which will be applied to our population-based vitamin D research study. This approach improves traceability of DBS results and potentially could be used broadly for other DBS measurands that require comparison to serum/plasma for their interpretation.

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Clinical validation study of dried blood spot for determining everolimus concentration in patients with cancer

European Journal of Clinical Pharmacology ◽

10.1007/s00228-017-2394-0 ◽

2017 ◽

Vol 74 (4) ◽

pp. 465-471 ◽

Cited By ~ 7

Author(s):

A. E. C. A. B. Willemsen ◽

L. M. Knapen ◽

Y. M. de Beer ◽

R. J. M. Brüggemann ◽

S. Croes ◽

...

Keyword(s):

Validation Study ◽

Dried Blood Spot ◽

Clinical Validation ◽

Patients With Cancer ◽

Blood Spot

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Solutions for hematocrit bias in dried blood spot hormone analysis

Bioanalysis ◽

10.4155/bio-2021-0119 ◽

2021 ◽

Vol 13 (16) ◽

pp. 1293-1308

Author(s):

Vera de Kleijne ◽

Isabelle Kohler ◽

Annemieke C Heijboer ◽

Mariëtte T Ackermans

Keyword(s):

Low Cost ◽

Analytical Techniques ◽

Dried Blood Spot ◽

Significant Interest ◽

Alternative Approaches ◽

The Impact ◽

Hormone Analysis ◽

Blood Spot

Over the last years, dried blood spot (DBS) sampling has gained significant interest due to development of analytical techniques combined with DBS, the simplicity and low cost of the method. Despite its wide use, DBS sampling can lead to inaccurate results due to the impact of the hematocrit (Hct) on the analysis. Some analytes have shown to be hardly impacted by Hct values. However, in other cases, a significant impact of Hct is observed, which requires the use of alternative approaches to circumvent this issue. This review describes the possible impact of Hct-related bias in DBS sampling in the context of hormone analysis and discusses the different methodologies that can be used to overcome this bias to ensure accurate results.

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Use of dried blood spot as an alternative method to estimate serum triglyceride in field studies

International Journal of Clinical Biochemistry and Research ◽

10.5958/2394-6377.2016.00016.2 ◽

2016 ◽

Vol 3 (1) ◽

pp. 55

Author(s):

M Hamsa ◽

H Raghunath ◽

BN Kruthi ◽

T Sibi Mandela

Keyword(s):

Serum Triglyceride ◽

Field Studies ◽

Dried Blood Spot ◽

Alternative Method ◽

Blood Spot

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Dried-Blood-Spot Technique to Monitor Direct Oral Anticoagulants: Clinical Validation of a UPLC–MS/MS-Based Assay

Analytical Chemistry ◽

10.1021/acs.analchem.8b02046 ◽

2018 ◽

Vol 90 (15) ◽

pp. 9395-9402 ◽

Cited By ~ 11

Author(s):

Kathrin I. Foerster ◽

Andrea Huppertz ◽

Andreas D. Meid ◽

Oliver J. Müller ◽

Timolaos Rizos ◽

...

Keyword(s):

Oral Anticoagulants ◽

Direct Oral Anticoagulants ◽

Dried Blood Spot ◽

Clinical Validation ◽

Blood Spot

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Assessing the impact of a nurse-delivered home dried blood spot service on uptake of testing for household contacts of hepatitis B-infected pregnant women across two London trusts

Epidemiology and Infection ◽

10.1017/s0950268815003325 ◽

2016 ◽

Vol 144 (10) ◽

pp. 2087-2097 ◽

Cited By ~ 3

Author(s):

P. KEEL ◽

G. EDWARDS ◽

J. FLOOD ◽

G. NIXON ◽

K. BEEBEEJAUN ◽

...

Keyword(s):

Hepatitis B ◽

Pregnant Women ◽

Hepatitis B Surface Antigen ◽

Baseline Period ◽

Vaccine Uptake ◽

Dried Blood Spot ◽

Household Contacts ◽

Home Based ◽

The Impact ◽

Blood Spot

SUMMARYDespite national guidance recommending testing and vaccination of household contacts of hepatitis B-infected pregnant women, provision and uptake of this is sub-optimal. The aim of this study was to evaluate the use of in-home dried blood spot (DBS) testing to increase testing and vaccination of household contacts of hepatitis B-infected pregnant women as an alternative approach to conventional primary-care follow-up. The study was conducted across two London maternity trusts (North Middlesex and Newham). All hepatitis B surface antigen-positive pregnant women identified through these trusts were eligible for inclusion. The intervention of in-home DBS testing for household contacts was introduced at North Middlesex Trust from November 2010 to December 2011. Data on testing and vaccination uptake from GP records across the two trusts were compared between baseline (2009) and intervention (2010–2011) periods. In-home DBS service increased testing uptake for all ages (P < 0·001) with the biggest impact seen in partners, where testing increased from 30·3% during the baseline period to 96·6% during the intervention period in North Middlesex Trust. Although impact on vaccine uptake was less marked, improvements were observed for adults. The provision of nurse-led home-based DBS may be useful in areas of high prevalence.

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Field Survey Measures of Olfaction

Field Methods ◽

10.1177/1525822x14547499 ◽

2014 ◽

Vol 26 (4) ◽

pp. 421-434 ◽

Cited By ~ 15

Author(s):

David W. Kern ◽

Kristen E. Wroblewski ◽

L. Philip Schumm ◽

Jayant M. Pinto ◽

Martha K. McClintock

Keyword(s):

Field Research ◽

Field Studies ◽

Population Based ◽

Olfactory Function ◽

Assessment Tools ◽

Odor Identification ◽

Survey Tool ◽

Odor Detection ◽

Health Studies ◽

The Impact

Population-based field research on human olfaction has been limited by a lack of feasible assessment tools. Previous olfactory survey research has measured only odor identification, with no research being done on odor detection (i.e., a person’s sensitivity to detect a particular odor). Laboratory studies suggest that deficits in both aspects of olfactory function may be related to physical health, mental health and cognition, social function, including overall quality of life, and even mortality. However, field studies are needed to validate and extend these findings in large representative samples. Here we describe the olfactory function field exam, an instrument that can be deployed in field environments by lay interviewers to evaluate both odor identification and odor detection rapidly, practically, and accurately. Use of this new survey tool in future field-based population health studies will elucidate the impact of olfactory function on a myriad of health and social conditions.

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