Oligonucleotides, composed of 2 to 20 nucleotide units, are increasingly utilized in disease diagnosis and therapeutic applications. They facilitate the introduction of DNA into immune cells, enabling genetic modifications to express chimeric antigen receptor proteins for cell-based immunotherapy. The molecular weight of oligonucleotides, a critical attribute, is analyzed to ascertain oligonucleotide types, purity, and quality, and to refine synthesis methods. Oligonucleotide molecular weight analysis also supports drug delivery system design and gene therapy research, playing a crucial role in biological studies and pharmaceutical development.
Studzińska, S. et. al. Talanta. 2018.
Figure 1. Oligonucleotide Molecular Weight Analysis
Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF) serves as a pivotal tool for determining oligonucleotide molecular weights. Using a chemical matrix, MALDI-TOF ionizes samples with a laser, accelerates ions to a detector, and measures the timing of detection, which correlates directly with molecular mass. Despite its high throughput, limitations exist, including reduced ionization efficiency and resolution, and potential damage to photosensitive oligonucleotides by intense laser exposure, restricting its use to oligonucleotides under 50 bases.
Electrospray ionization mass spectrometry (ESI-MS) represents another fundamental technique for molecular weight analysis, ideal for oligonucleotides over 50 bases. ESI-MS applies high-voltage aerosol generation from a liquid sample to ionize target oligonucleotide molecules into a variety of charge states represented by different mass spectra, these states can be deconvolved into mother peaks to identify oligonucleotide and potential impurities. This gentler ionization process preserves the integrity of photosensitive oligonucleotides.
MtoZ Biolabs provides top-tier oligonucleotide molecular weight analysis, employing diverse high-resolution mass spectrometry platforms to develop and validate tailored analytical methods. These precise measurements are crucial for characterizing synthetic oligonucleotides, their impurities, metabolites, and post-synthetic modifications. For further information on our oligonucleotide services, welcome to consult for free!