Development Of An Ultra-Sensitive Assay For Anti-Sense Oligonucleotide Quantification

By Ji Jiang, Eshani Nandita, Lei Xiong, SCIEX

Oligonucleotide therapeutics and gene therapies are rapidly gaining attention as their potency improves and delivery challenges are addressed. Modalities such as ASOs are becoming more important due to their high specificity and capability for treating formerly undruggable targets. Recently, an increase in the number of candidates entering clinical trials and approvals have been observed, triggering increased demand for highly sensitive and robust quantitative bioanalytical methods to understand their pharmacokinetic profiles and metabolism. Conventional approaches for oligonucleotide bioanalysis involve ligand-binding assays (LBA) and fluorescence-based detection primarily due to achieving low detection limits. While such techniques can be highly sensitive, there are limitations in coverage of the linear dynamic range (LDR). Moreover, both assays lack specificity in distinguishing oligonucleotide products from related impurities and metabolites. Furthermore, assays utilizing fluorescence-based detection often suffer from low throughput due to extensive run times. Orthogonal technologies such as mass spectrometry (MS) have been routinely employed for bioanalytical studies of oligonucleotides since the platform is capable of both differentiating between target oligonucleotides and associated components: and providing high-throughput capabilities. However, the extent of MS use to date has been limited by its ability to quantify the ultra-low analyte levels in complex biological matrices.

Learn about a new level in sensitivity for challenging analytes in matrix that opens doors for accurate bioanalysis and metabolism studies with excellent specificity not achievable with orthogonal methods.