Short-term stabilities of 21 amino acids in dried blood spots

Abstract

BACKGROUND: Dried blood spots (DBSs) have potential use in remote health applications for individual and population diagnosis, and can enable epidemiological surveillance for known and unknown diseases. The preparation and transportation of DBSs from remote settings often exposes these cards to extreme environmental stress that may impact the quality of the diagnostic data. Given these risks, it is essential to investigate the individual stabilities of biomarkers in DBSs. This paper details the stability of routinely-analyzed amino acids (AAs) on DBSs under environmental conditions that simulate a global health workflow. METHODS:The extractions of 21 AAs from three sets of DBSs prepared on cellulose and cotton filter paper were optimized for quantitation by dansylation-UPLC/MRM-MS. The effects of sunlight exposure, temperature, humidity, and storage time were studied. RESULTS:The AAs were stable in DBSs after 4-hour sunlight exposure, and after storage at -20 and 4 o C for 30 days. At 25 and 40 o C, only 7 AAs showed significant concentration decreases over time, while 2 showed concentration increases. The changes were accelerated by high humidity. Histidine was the least stable AA under the conditions tested. CONCLUSIONS:This study provides quantitative data on the short-term stabilities of 21 AAs in DBSs on cellulose and cotton-based filter paper, under environmental conditions that simulate a globalhealth workflow. These results highlight the importance of assessing the stability of clinically-relevant biomarkers in DBSs. Based on the measured stabilities, we recommend that higher-temperature and high-humidity storage of DBS samples be avoided for AA analysis in remote health applications.

Concentration Determination of >200 Proteins in Dried Blood Spots for Biomarker Discovery and Validation

“…Peptides were purified using HPLC and the parent mass to charge ratio confirmed using an Ultraflex III-MALDI TOF/TOF Mass Spectrometer (Bruker LTD., Milton, ON). The purity of each peptide was determined using capillary zone electrophoresis on a 7100 Capillary Electrophoresis System (Agilent Technologies), as previously described (30,31), and the absolute concentration of each peptide was measured in-house using LC/MS-based amino acid analysis (32). Briefly, peptide standards were acid hydrolyzed and the resulting amino acids were dansylated (32) and subjected to HPLC-MS/MS (1290 Infinity HPLC online with 6490 triple Quad MS) (Agilent-Technologies) operated in dynamic MRM mode.…”

Commercial initiation of feather hydrolysate as supreme fertilizer: A smart bio-cleaning strategy of poultry waste

“…5a). This is due to the oxidizing effect of thioester group of different amino acids present in feather hydrolysate [27]. This study indicated good stabilities of liquid fertilizer during the temperature transitions.…”

High recovery, point‐of‐collection plasma separation from blood using electrospun polyacrylonitrile membranes

“…This indicates that the amino acids recovered from the synthesized DPS systems are very comparable with those from the pure plasma. Some amino acids are away from the diagonal line probably owing to the following combined effects: (a) compared to pure plasma, the Absorbent 2 may have unspecific binding to some amino acids; (b) amino acid concentrations could change in DBS cards during the drying process with the changes varying among different amino acids 55 ; and (c) similar to albumin protein recoveries, there might be underestimations of plasma recoveries in the lab‐made systems due to the evaporation of plasma during the weighting process.…”