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bioRxiv · 10.1101/2021.06.05.447195

Quantification of Antisense Oligonucleotides by Splint Ligation and Quantitative Polymerase Chain Reaction

Shin, M.·Krishnamurthy, P. M.·Watts, J. K.
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Abstract

Reliable detection and quantification of antisense oligonucleotides (ASOs) in experimental and clinical specimens is essential to understand the biological function of novel oligonucleotide-based therapeutics. In this study, we describe a method to detect and quantify ASOs in biological samples, whereby the ASO acts as a splint to direct the ligation of complementary probes and quantitative real-time PCR was used to monitor ligation products. Low levels of 2'-O-MOE gapmer ASO in serum, liver, kidney, lung, heart, muscle, and brain tissues can be detected over a 6-log linear range for detection using this method. This method allows quantification of various types of chemically modified ASOs, including PS linkage, 2'-OMe, 2'-O-MOE, locked nucleic acid (LNA), and siRNA. This method does not require probe modifications, and can be performed using standard laboratory equipment; making it a fast, sensitive, and reliable technique that can be widely applied. This detection method may find potential applications in detection of therapeutic oligonucleotides in biological samples.

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Shin, M., Krishnamurthy, P. M., Watts, J. K.. 2021-06-05. Quantification of Antisense Oligonucleotides by Splint Ligation and Quantitative Polymerase Chain Reaction. https://doi.org/10.1101/2021.06.05.447195

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