Expanding the chemical repertoire of aptamers Aptamers offer distinct advantages over conventional small molecules or antibodies due to their high affinity and specificity. Additional benefits, including small size and ease of modification, further enhance their biomedical potential. Nonetheless, their interaction capabilities remain constrained by the limited chemical diversity of natural nucleobases, restricting the repertoire of targets accessible in vitro and in vivo. This review highlights strategies to overcome these limitations by expanding the chemical diversity of aptamers, including sugar, backbone, and nucleobase modifications, as well as selection approaches for their identification. We discuss structural insights into modified aptamers and explain their potential in practical applications. Finally, key challenges are identified that must be addressed to fully achieve the therapeutic and diagnostic utility of chemically modified aptamers.

Online now: Expanding the chemical repertoire of aptamers

Happy to share our review article @cp-trendschem.bsky.social on modified aptamers. Congrats to all authors!
@pasteur.fr @ipdbsc.bsky.social @cnrs.fr
doi.org/10.1016/j.tr...

Selection of Ruthenium Polypyridyl Complex-Modified Aptamers for Photodynamic Therapy against Streptococcus Pneumonia Photodynamic therapy (PDT) harnesses the combination of light, oxygen, and photosensitizers to induce cell death via reactive oxygen species (ROS) formation. Given its intrinsic properties, PDT repres...

Thrilled to share our article just published in @J_A_C_S on the selection of Ru-modified aptamers! Fantastic collaboration with @hollensteinlab.bsky.social, congratulations to all authors! doi.org/10.1021/jacs...

Selection of Ruthenium Polypyridyl Complex-Modified Aptamers for Photodynamic Therapy against Streptococcus Pneumonia Photodynamic therapy (PDT) harnesses the combination of light, oxygen, and photosensitizers to induce cell death via reactive oxygen species (ROS) formation. Given its intrinsic properties, PDT repres...

Thrilled to share our article @J_A_C_S on the selection of Ru-modified aptamers. 7 years in the making. Congrats to all authors! Great collaboration with @gassergroup.bsky.social
pubs.acs.org/doi/full/10....
@pasteur.fr @ipdbsc.bsky.social @cnrs.fr @pierrenicolasbizat.bsky.social

Probing three-dimensional cyclooctatetraene for nucleobase modification in aptamer selection Communications Chemistry, Published online: 15 September 2025; doi:10.1038/s42004-025-01629-5Chemical modifications of aptamers can enhance binding properties, however, the design of suitable functional groups remains challenging. Here, the authors introduce cyclooctatetraene (COT)-modified nucleotides in SELEX experiments, identifying COT-aptamers with low nM dissociation constants, highlighting the potential of three-dimensional ligands in aptamer discovery.

Just out: Probing three-dimensional cyclooctatetraene for nucleobase modification in aptamer selection

Interested by 3D modified aptamers? Then check out our recent article by undergraduate student Charlotte and postdoc Usman.
nature.com/articles/s4200…
@ipdbsc.bsky.social @pasteur.fr @cnrs.fr

Very happy to share our preprint @ChemRxiv on the selection of Ru-modified aptamers. Long in the making. Congrats to all authors. Great collaboration with @gassergroup.bsky.social
@pasteur.fr @ipdbsc.bsky.social @cnrs.fr
10.26434/chemrxiv-2025-dd90p

Very much looking forward presenting our research at #biotrans2025 in Basel. Thanks again for the kind invitation!

Towards the enzymatic labelling of oligonucleotides with triantennary N-acetyl galactosamine The inclusion of chemical modifications into oligonucleotides stabilizes their backbones against nuclease mediated degradation and improves their biological activity. Even though cellular, tissue, and...

Very happy to share out new pre-print on the enzymatic GalNAc-labelling of oligonucleotides. Big congrats to undergraduate student Elisa and graduate student @pierrenicolasbizat.bsky.social!
chemrxiv.org/engage/chemr...
@pasteur.fr @ipdbsc.bsky.social @cnrs.fr

ReNAissance : révolutionner les traitements antiviraux grâce à l’ARN messager Et si notre organisme devenait une usine à médicaments, capable de produire lui-même des anticorps pour lutter contre les virus ?

Et si notre organisme devenait une usine à médicaments, capable de produire lui-même des anticorps pour lutter contre les virus ? C’est le défi ambitieux que relève ReNAissance !

🤝 @cnrs-bretagneloire.bsky.social @inserm.fr

very happy to work with my colleague Bruno Pitard on therapeutic RNAs. We thank @inserm.fr for selecting our project and for the very generous funding!
@pasteur.fr @ipdbsc.bsky.social @hollensteinlab.bsky.social

Image décorative. © AdobeStock

L’Inserm présente aujourd’hui les quinze projets sélectionnés dans le cadre du programme Impact Santé.

Lire le communiqué : presse.inserm.fr/impact-sante...

Thank you so much for highlighting our work!

Natural, modified and conjugated carbohydrates in nucleic acids Storage of genetic information in DNA occurs through a unique ordering of canonical base pairs. However, this would not be possible in the absence of the sugar–phosphate backbone which is essential fo...

This review is from @hollensteinlab.bsky.social, @debashisdhara.bsky.social and Laurence Mulard at @pasteur.fr

'Natural, modified and conjugated carbohydrates in nucleic acids'

#OpenAccess 🔓

pubs.rsc.org/en/content/a...

Special thank to
Chemical Communications editor Claire Harding, who strongly suggested transfer to
@chemsocrev.bsky.social after our submission!

Natural, modified and conjugated carbohydrates in nucleic acids Storage of genetic information in DNA occurs through a unique ordering of canonical base pairs. However, this would not be possible in the absence of the sugar–phosphate backbone which is essential fo...

Thrilled to share our article published
@chemsocrev.bsky.social on sugar modified nucleic acids. Congrats to Debashis! Great collaboration with Laurence Mulard. @pasteur.fr @ipdbsc.bsky.social @chem4life.bsky.social @cnrs.fr
pubs.rsc.org/en/content/a...

Thank you very much!

Congratulations !

Fantastic opportunity!

Probing three-dimensional cyclooctatetraene as nucleobase modification in aptamer selection

Authors: Greta Charlotte Dahm, Usman Akhtar, Alix Bouvier-Müller, Laura Lim, Fabienne Levi-Acobas, Pierre Nicolas Bizat, Germain Niogret, Julian Tanner, ...
DOI: 10.26434/chemrxiv-2025-cglxw

Probing three-dimensional cyclooctatetraene as nucleobase modification in aptamer selection Decoration of aptamers with chemical modifications at the level of nucleobases grants access to alternative binding modes which often result in improved binding properties. Most functional groups invo...

Very happy to share our new preprint on the selection of COT-modified aptamers. Great work by undergraduate student Charlotte. Congrats to all!
chemrxiv.org/engage/chemr...
Stay tuned for the published version.
@pasteur.fr @chem4life.bsky.social @hollensteinlab.bsky.social @chemrxiv.bsky.social

Merci beaucoup!

Katalin Karikó, la reine de l'ARNm Les travaux révolutionnaires de la biochimiste Katalin Karikó et du médecin Drew Weissman ont ouvert la voie à l’utilisation thérapeutique de l’ARNm avec un premier cas mondialement reconnu : celui de...

Happy to share a short interview (in french) on the synthesis of RNA oligonucleotides. Thanks to @franceculture.fr and @institutpasteur.bsky.social for the invitation.
@hollensteinlab.bsky.social @cnrs.bsky.social @chem4life.bsky.social
www.radiofrance.fr/francecultur...

@pasteur.fr @chem4life.bsky.social

Thrilled to share our review on biocatalytic methods for the synthesis of (modified) oligonucleotides. Congratulations to Pierre Nicolas and Nazarii! Thank you to Dr. Juan Jin and @rubenragg.bsky.social for their invitation!https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cbic.202400987

Long oligos: direct chemical synthesis of genes with up to 1728 nucleotides The longest oligos that can be chemically synthesized are considered to be 200-mers. Here, we report direct synthesis of an 800-mer green fluorescent protein gene and a 1728-mer Φ29 DNA polymerase gen...

Impressive work, 800 nt long oligo obtained SPOS:
pubs.rsc.org/en/content/a...

It was nice to be in the jury of Joseph Boissieras at the Institut Curie in Orsay yesterday and to meet, among others, with @hollensteinlab.bsky.social. Thanks to @granzhan.bsky.social for the invitation.
Congratulations to the new doctor. All the very best for your future Joseph.