MSACL 2016 US Abstract

Analyte Stability from Dried Blood Collected on HemaSpot-HF™ Devices

James Hill (Presenter)
Spot On Sciences, Inc.

Authorship: Dr. Jeanette R. Hill1, Dr. James E. Hill1, Ms. Susan C. Leininger1, Mr. Jason R. Wright1, Dr. Robert Taylor1, Dr. John Repass2
1) Spot On Sciences, Austin TX, 2) ARQ Genetics, Bastrop TX

Short Abstract Representative analytes including small molecules, proteins and nucleic acids, were examined for their long-term storage stability on HemaSpot-HF devices stored at various temperatures and humidities. Small molecules cortisol, nifedipine, and tolbutamide enzyme protein β-D-Galactosidase and nucleic acids micro RNA; miR155, messenger RNA; β -Actin and ribosomal RNA; 18S were followed over the course of 12 months while stored at temperatures from -20 oC to 45 oC. Shorter term stability trials at >95% humidity were also followed over 4 weeks from room temperature to 45 oC. Analysis of the small molecules was performed by LC-MS/MS as was analysis of the enzymatic activity of β-D-Gal, by monitoring the formation of 4-methylumbelliferone from 4-MU- β-D-galactose. Analysis of the nucleic acids was performed by qPCR.

Long Abstract

Introduction

The stability of small molecules, proteins and nucleic acids in dried blood samples from the HemaSpot-HF™ Blood Collection Device were tested over a range of temperatures, humidity, and time.

Materials and Methods

Pooled whole blood was spiked with exogenous test markers and 80 μL were applied to HemaSpot-HF™ devices. The devices were closed immediately and all of the samples were placed at their respective temperatures (-80°C, -20°C, 4°C, 22°C/ambient, 37°C, 45°C and 60°C) and humidity levels (ambient/40-50% and high/95% humidity) for time periods that ran from 0 to 12 months.

At each time point a single wedge was removed for extraction and quantitation of the three small molecules. Analysis was performed by LC-MS/MS. A second wedge from each form was incubated for 24 hrs at 37 oC in 200 μL of a 200 μmole/L solution of 4-MU-β-D-galactose. Enzymatic activity of β-D-Galactosidase was determined by measuring the amount of 4-methylumbelliferone generated during the 24 hr incubation. Total RNA was isolated from two wedges for qPCR analysis.

Results

Small molecules (nifedipine, tolbutamide and cortisol), proteins (beta-galactosidase) and nucleic acids (miRNA:miR155, mRNA: b-Actin & rRNA: 18S), in dried blood samples stored in HemaSpot-HF™ showed high stability at temperatures from -20 to 37 °C and ambient humidity for 12 months. Reduced stability was observed for some analytes from DBS stored at higher temperatures (45°C) and higher humidity (95%) after 6 months as compared to those at the lower temperatures.

Conclusions

Dried blood samples on HemaSpot-HF™ devices demonstrated high stability over 12 months at storage temperatures from -80 oC to 37 oC for several analytes including small molecules, proteins, and nucleic acids.

References & Acknowledgements:

Financial Disclosure

IP Royalty: no

Planning to mention or discuss specific products or technology of the company(ies) listed above:

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