Bioconjugate Chemistry最新文献

{"title":"Peptide Sequence and Backbone Conjugation Chemistry Direct Alginate Hydrogel Bioactivity for Human Mesenchymal Stem Cell Expansion","authors":"Eli R. Broman,&nbsp;Pranati P. Mondkar,&nbsp;Marizela Delic-Schlumbohm,&nbsp;Susan Jordan,&nbsp;Samira M. Azarin,&nbsp;Theresa M. Reineke","doi":"10.1021/acs.bioconjchem.6c00209","DOIUrl":"https://doi.org/10.1021/acs.bioconjchem.6c00209","url":null,"abstract":"<p>Peptide-functionalized alginate hydrogels are a promisingbiomaterialcandidate for supporting the expansion of adherent human mesenchymalstem cells (hMSCs) toward therapeutic applications. Despite widespreadRGD-modified alginates, critical aspects of peptide conjugation chemistry,including verification of the coupling orientation and role of aminoacids flanking the core RGD motif, remain underexplored. Through systematicmaterial characterization and peptide sequence design, this work addressesthese important research gaps. We first thoroughly characterized thealginate backbone composition via ¹H NMR spectroscopy usingpeak deconvolution, providing more distinct quantitation of alginatebackbone composition and conjugation sites. We then coupled 4 peptidesequences systematically designed to probe the effect of the spacerN-terminal to RGD, either glycine–glycine–phenylalanine–threonine(GGFT) or cysteine–glycine–phenylalanine–threonine(CGFT), and the presence or absence of a C-terminal serine–proline(SP) motif. As a spacer, we capitalized on using phenylalanine (F),as opposed to the previously published tyrosine (Y), to mitigate sidereactions with the phenolic hydroxyl group while retaining aromaticprotons (δ ∼7.2–7.4 ppm) for a quantitative degreeof substitution and coupling efficiency characterization via ¹H NMR. Further included in our design was polar threonine(T), to enhance the aqueous solubility of the overall peptide spacer.Critically, we provided evidence (previously only assumed) that amidebond formation occurred through the peptide N-terminus as intended(versus the unwanted side reaction of coupling the guanidinium groupof arginine (R) to alginate’s carboxyl) using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholiniumchloride (DMTMM) coupling. The attachment, spreading, and proliferationof hMSCs to hydrogel films of this well-characterized alginate series(cross-linked with calcium chloride) were then examined to understandthe role of peptide sequence on performance. Alginates functionalizedwith GGFTRGD or CGFTRGD failed to support hMSC expansion, whereasinclusion of the C-terminal SP sequence (yielding GGFTRGDSP or CGFTRGDSP)promoted robust cell attachment and a &gt;10-fold increase in thefinalcell number, demonstrating the essential role of SP immediately C-terminalto RGD, which more closely resembles the sequence of native fibronectin.Together, the characterization methods and sequence/activity relationshipsestablished herein provide a foundation for the rational design ofwell-characterized and reproducible peptide-alginate hydrogels forscalable hMSC expansion and therapeutic applications.</p>","PeriodicalId":29,"journal":{"name":"Bioconjugate Chemistry","volume":"37 9","pages":"1833–1844"},"PeriodicalIF":4.5,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148974256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of a Mirror-Image VHH Antibody with VEGF-Inhibitory Activity and Characterization of Its Immunogenicity","authors":"Kayuu Maeda,&nbsp;Manrei Yonemura,&nbsp;Keisuke Aoki,&nbsp;Saaya Imahori,&nbsp;Naoya Iwamoto,&nbsp;Shogo Oka,&nbsp;Jyoji Morise,&nbsp;Katsuaki Higashi,&nbsp;Shinya Oishi,&nbsp;Motohiro Nonaka","doi":"10.1021/acs.bioconjchem.6c00264","DOIUrl":"https://doi.org/10.1021/acs.bioconjchem.6c00264","url":null,"abstract":"<p>Immunogenicity remains a major challenge in antibodytherapeutics.Antibodies can be recognized as foreign by immune cells, leading tothe induction of antidrug antibodies that ultimately compromise therapeuticefficacy. This response is primarily driven by proteolytic processingwithin antigen-presenting cells and the subsequent presentation ofpeptide fragments to T cells via major histocompatibility complexmolecules. As mirror-image proteins are expected to exhibit resistanceto proteolytic degradation, we have been developing mirror-image VHHantibodies composed entirely of <span>d</span>-amino acids. Previously,we generated a <span>d</span>-VHH antibody with specific binding activityto vascular endothelial growth factor A (VEGF-A) and demonstratedthat it did not induce antidrug IgG antibodies in a mouse model. However,this <span>d</span>-VHH antibody did not inhibit the VEGF–VEGFreceptor interaction, and the immunological processes leading to thelack of IgG antibody induction had not been experimentally demonstrated.In this study, we constructed a new phage-displayed library to improvethe hit rate and enable the efficient chemical synthesis of <span>d</span>-VHH antibodies. Using this library, mirror-image screening against <span>d</span>-VEGF identified new VHH antibody sequences with specific binding.The synthesized <span>d</span>-VHH antibody inhibited the VEGF–VEGFreceptor interaction. Next, we investigated the immunogenicity of <span>d</span>-VHH antibody using a conventional <span>l</span>-VHH antibodyas a reference. The <span>d</span>-VHH antibody resisted enzymatic degradationand, in a mouse model, did not induce inflammatory cytokine production,T-cell responses, or the formation of antidrug antibodies againstthe administered antibody. Collectively, these findings highlightthe potential of inhibitory <span>d</span>-VHH antibodies as a promisingapproach for developing low-immunogenic therapeutic antibodies.</p>","PeriodicalId":29,"journal":{"name":"Bioconjugate Chemistry","volume":"37 9","pages":"1845–1856"},"PeriodicalIF":4.5,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148964585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of Human Milk Oligosaccharides–Fluoroquinolone Conjugates and Investigation of Their Antimicrobial Activity","authors":"Liza Nguyen Van Sang,&nbsp;Emil Lindbäck,&nbsp;Magne O. Sydnes","doi":"10.1021/acs.bioconjchem.6c00334","DOIUrl":"https://doi.org/10.1021/acs.bioconjchem.6c00334","url":null,"abstract":"<p>The copper-catalyzed azide–alkyne cycloadditionreactionwas applied to conjugate four human milk oligosaccharides (HMOs) withantimicrobial fluoroquinolones (FQs) (ciprofloxacin and sparfloxacin)to obtain a total of 12 per-<em>O</em>-acetylated and unprotectedHMO–FQ conjugates. These compounds underwent antimicrobialtesting against Gram-positive (<em>Streptococcus agalactiae</em>, <em>Enterococcus faecalis</em>, and <em>Staphylococcus aureus</em>) and Gram-negative (<em>Escherichia coli</em> and <em>Pseudomonas aeruginosa</em>) bacteria. The HMO–FQ conjugates exhibited the most significantantimicrobial activity against <em>E. coli</em> and <em>S. aureus</em> reaching minimum inhibitoryconcentration as low as 1.56 μM and 3.13 μM, respectively.A general trend was that per-<em>O</em>-acetylated HMO–FQconjugates exhibited higher antimicrobial activity than their unprotectedcounterparts. The antimicrobial activity of the tested HMO–FQconjugates is expected to arise from the ciprofloxacin and sparfloxacinmoieties because per-<em>O</em>-acetylated and unprotectedHMOs did not exhibit any antimicrobial activity. Additionally, theHMO–FQ conjugates displayed no cytotoxicity as evident fromtest on two cell lines (HepG2 and MRC5).</p>","PeriodicalId":29,"journal":{"name":"Bioconjugate Chemistry","volume":"37 9","pages":"1867–1876"},"PeriodicalIF":4.5,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148964589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Beyond Cytotoxic Payloads for Antibody Drug Conjugates─A Medicinal Chemistry Perspective","authors":"Allan Jordan,&nbsp;Stuart Best,&nbsp;Joshua Greally","doi":"10.1021/acs.bioconjchem.6c00322","DOIUrl":"https://doi.org/10.1021/acs.bioconjchem.6c00322","url":null,"abstract":"<p>Despite significant research and investment, antibody–drugconjugates (ADCs) primarily rely on a limited number of broadly cytotoxicpayloads that contribute significantly to toxicity. More recently,there has been a migration toward mechanistically targeted payloads,pairing improved antibodies with small molecules that act on disease-specificbiology, improving precision and tolerability. Designing these next-generationpayloads means rethinking some of our design metrics and guidelinesderived from traditional medicinal chemistry: properties such as LogD,p<em>K</em>_a, permeability, efflux, and metabolicstability must be carefully balanced to ensure efficient intracellularrelease while limiting systemic exposure. Here we discuss our observationsaround these properties and suggest design rules and guidelines forthe optimization of next-generation ADC payloads.</p>","PeriodicalId":29,"journal":{"name":"Bioconjugate Chemistry","volume":"37 9","pages":"1798–1803"},"PeriodicalIF":4.5,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148964590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface Functionalization of Small Extracellular Vesicles Derived from Caco-2 and HEK293T Cells in the Neutralization of Shiga Toxin 1 Subunit B","authors":"Krzysztof Mikolajczyk,&nbsp;Anna Bereznicka,&nbsp;Liliana Czernek,&nbsp;Alice Gualerzi,&nbsp;Luana Forleo,&nbsp;Marzia Bedoni,&nbsp;Norbert Lodej,&nbsp;Pawel Migdal","doi":"10.1021/acs.bioconjchem.6c00243","DOIUrl":"https://doi.org/10.1021/acs.bioconjchem.6c00243","url":null,"abstract":"<p>Shiga toxins (Stx) are key virulencefactors of Shiga toxin-producing <em>Escherichia coli</em> (STEC), which are responsible forsevere foodborne infections that can progress to hemolytic-uremicsyndrome (HUS). Currently, no specific antitoxin therapies are available.In this study, we devised a glycoengineering strategy utilizing Functional-Spacer-Lipid(FSL) conjugates to create small extracellular vesicles (sEVs)-baseddecoy receptors for Shiga toxin type 1 (Stx1). sEVs isolated fromhuman Caco-2 and HEK293T cells were functionalized with Gb3 trisaccharide(Galα1→4Galβ1→4Glc)-containing FSL conjugates,yielding Gb3-decorated vesicles displaying the Galα1→4Galepitope. Characterization of FSL-modified sEVs confirmed that FSLincorporation did not adversely affect sEV morphology, size distribution,or surface charge. Western blotting and bead-assisted flow cytometryverified the presence of exosomal markers (CD9 and CD63) and the Gb3epitope on modified vesicles. Gb3-tagged sEVs from both cell typesexhibited high specificity in binding Stx1B, while control vesiclescarrying Galili epitope (Galα1→3Galβ1→4GlcNAc),lacking Stx1B binding, demonstrated negligible binding. Gb3-expressingCaco-2 cell-based assays revealed that Gb3-decorated sEVs markedlyreduced Stx1B binding to Caco-2 cells, indicating effective competitionwith cellular receptors. Furthermore, glycoengineered sEVs did notimpair Caco-2 cell viability at concentrations sufficient for Stx1Bsequestration. These findings establish FSL-mediated glycoengineeringas a rapid and versatile approach for generating sEV-based decoy receptorsthat effectively bind Stx1B. Gb3-containing human sEVs may serve asan agent for neutralizing Stx1B and potentially other glycan-bindingtoxins, supporting the development of promising next-generation antitoxintherapeutics.</p>","PeriodicalId":29,"journal":{"name":"Bioconjugate Chemistry","volume":"37 8","pages":"1665–1677"},"PeriodicalIF":4.5,"publicationDate":"2026-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148769466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design, Synthesis, and Physicochemical Characterization of Boronic Acid-Linked Cationic Lipids: Aggregation, Diol Recognition, Membrane Perturbation, and DNA Complexation","authors":"Nirmal Chakraborty,&nbsp;Bappa Maiti,&nbsp;Vedant Tripathi,&nbsp;Santanu Bhattacharya","doi":"10.1021/acs.bioconjchem.6c00180","DOIUrl":"10.1021/acs.bioconjchem.6c00180","url":null,"abstract":"<p>Boronicacids are attractive functional groups because they formreversible covalent bonds with cis-diols, enabling selective recognitionof saccharides, glycoproteins, and related biomolecules. Althoughwidely exploited in sensing and glycobiology, their incorporationinto lipid-based systems remains relatively unexplored. Integratingboronic-acid-mediated molecular recognition into amphiphilic frameworkswhile preserving controlled self-assembly and biomolecular interactionscontinues to be a significant challenge. Here, we report the design,synthesis, and characterization of a new series of cationic amphiphilesincorporating aromatic boronic acids of differing acidity. Phenylboronicacid (p<em>K</em>_a ∼ 9.3) and pyridylboronicacid (p<em>K</em>_a ∼ 5.3) were conjugatedeither to α-tocopherol or to a linear C₁₆ alkyl chain,yielding four lipids, TPhBA, TPyBA, C₁₆PhBA, and C₁₆PyBA, that provide a systematic platform to probe the influenceof headgroup p<em>K</em>_a and hydrophobic architecture.Physicochemical analysis showed that pyridyl derivatives exhibitedhigher critical aggregation concentrations and zwitterionic characterat neutral pH, while phenyl derivatives formed aggregates at lowerconcentrations with high surface charge values. Small-angle X-raydiffraction, TEM, and AFM confirmed variations in bilayer packinggeometry and aggregate morphology. Preferential carbohydrate interactivebehavior was demonstrated through alizarin red S assays, where bothphenyl and pyridinyl boronic acid derivatives showed stronger diolbinding. 1,2-dipalmitoylphosphatidylcholine (DPPC) membrane studiesshowed that tocopherol-based lipids markedly disrupted the gel-to-liquidcrystalline transition, whereas C₁₆ derivatives causedonly modest perturbations. DNA-binding assays further revealed thatpyridyl derivatives formed more stable lipoplexes, while phenyl analoguesfacilitated easier DNA release. Collectively, these findings demonstratethat boronic acid headgroup acidity and hydrophobic architecture governaggregation, diol recognition, membrane interactions, and DNA complexation,highlighting their potential as responsive materials for membraneengineering and delivery applications.</p>","PeriodicalId":29,"journal":{"name":"Bioconjugate Chemistry","volume":"37 8","pages":"1611–1621"},"PeriodicalIF":4.5,"publicationDate":"2026-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148560225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chemical Strategies for Ferritin Nanocage Functionalization: A Viewpoint","authors":"Yang Liu,&nbsp;Yi Xiao,&nbsp;Jiuyang He,&nbsp;Minmin Liang","doi":"10.1021/acs.bioconjchem.6c00315","DOIUrl":"10.1021/acs.bioconjchem.6c00315","url":null,"abstract":"<p>Asa highly symmetrical and endogenous protein-based drug deliverysystem, ferritin nanocage has garnered tremendous attention in nanomedicinedue to its exceptional biocompatibility, dynamic self-assembly behavior,and intrinsic receptor-mediated targeting capabilities. With the rapidevolution of bioconjugation chemistry and protein engineering, thefunctional manipulation of ferritin has transitioned from passivephysical encapsulation to precise, site-specific engineering of ferritinarchitectures. This Viewpoint systematically highlights the multidimensionalbioconjugation strategies of ferritin and its relatives. We specificallyfocus on the biochemical principles driving genetic fusion engineering,classic covalent chemical conjugation, modular bioorthogonal assembly,and the in situ construction of catalytic centers within the innercavity. These chemistries are not merely incremental refinements.They unlock entirely new therapeutic and diagnostic capabilities,including single-dose tumor-lethal chemotherapy, high-sensitivitymultimodal/nuclear imaging, targeted protein degradation, ultrapurenanovaccines, and inflammation intervention. This Viewpoint aims toprovide a chemically grounded and forward-looking roadmap for thenext generation of ferritin engineering.</p>","PeriodicalId":29,"journal":{"name":"Bioconjugate Chemistry","volume":"37 8","pages":"1516–1522"},"PeriodicalIF":4.5,"publicationDate":"2026-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148576183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancement of Coiled-Coil Stability via Interhelical Click Chemistry Stapling","authors":"Tessa J. Posey,&nbsp;Jacquelyn E. Blum,&nbsp;Joshua E. Meisenhelter,&nbsp;William J. Rears,&nbsp;Darrin J. Pochan,&nbsp;Jeffery G. Saven,&nbsp;Christopher J. Kloxin","doi":"10.1021/acs.bioconjchem.6c00270","DOIUrl":"https://doi.org/10.1021/acs.bioconjchem.6c00270","url":null,"abstract":"<p>Coiled coil peptideassemblies are useful scaffolds forbiomolecularand materials design, but their function often depends on preservingthe folded oligomeric state after chemical modification or exposureto demanding conditions. While many peptide-stapling strategies stabilizeindividual α-helices, approaches that covalently reinforce higher-orderarchitectures remain less developed. Here, we introduce an “assemble-and-click”strategy for interhelical stapling of a designed tetramer coiled coil.Cysteine and vinyl sulfonamide handles were positioned at symmetry-relatedsites that are brought into proximity by coiled-coil assembly, enablingpH-triggered thiol-Michael coupling after tetramer formation. LC-MSsupports rapid formation of covalently linked dimeric products, SEC-MALSindicates that the stapled peptide retains the expected tetramericassembly state, and circular dichroism shows markedly enhanced thermalrobustness, with no cooperative unfolding observed up to 90 °Cunder the conditions examined. This approach provides a chemicallyprogrammable route to reinforcing higher-order coiled coil assemblieswhile preserving their oligomeric architecture.</p>","PeriodicalId":29,"journal":{"name":"Bioconjugate Chemistry","volume":"37 8","pages":"1545–1550"},"PeriodicalIF":4.5,"publicationDate":"2026-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148769431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cell Surface Deazaflavin-Diazirine Energy-Transfer (DarT) Photoproximity Labeling Using Antibody Conjugates","authors":"Judith M. Müchler,&nbsp;Leander B. Crocker,&nbsp;Max Ruwolt,&nbsp;Kristin Kemnitz-Hassanin,&nbsp;Christian P. R. Hackenberger","doi":"10.1021/acs.bioconjchem.6c00247","DOIUrl":"https://doi.org/10.1021/acs.bioconjchem.6c00247","url":null,"abstract":"<p>Elucidating protein–protein interactions playsa crucialpart in understanding disease mechanisms and advancing pharmacologicalresearch. Photocatalytic proximity labeling using antibody–catalystconjugates enables the highly target-specific analysis of protein–proteininteractions on the cell surface without altering the native cellularstate through genetic manipulation. Here, we describe an extensionof the deazaflavin–diazirine energy-transfer (DarT) labelingplatform through the development and evaluation of trastuzumab–deazaflavin(Tra–dFl) conjugates for mapping the extracellular microenvironmentof human epidermal growth factor receptor 2 (HER2). Four Tra–dFlconjugates were synthesized via azide–DBCO click chemistry,varying in PEG linker size and catalyst loading: Tra–PEG0–dFl,Tra–PEG6–dFl, Tra–PEG12–dFl, and Tra-bis-dFl,exhibiting a branched linker for dual attachment. Imaging and proteomicpulldown experiments revealed that linker size influences biotinylationefficiency and proteomic enrichment, resulting in Tra–PEG12–dFlemerging as the most effective construct, enabling the enrichmentof cancer-associated cell surface proteins in HER2-positive SK-BR-3cells. Evaluation of catalyst valency using a branched linker resultedin fewer enriched proteins, suggesting that linker architecture isa more critical parameter for conjugate performance than increasedcatalyst loading. Together, these findings provide guidelines forantibody-based deazaflavin conjugates and expand the applicabilityof DarT labeling for target-directed surfaceome mapping.</p>","PeriodicalId":29,"journal":{"name":"Bioconjugate Chemistry","volume":"37 8","pages":"1678–1688"},"PeriodicalIF":4.5,"publicationDate":"2026-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148769651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"RNA Size and Structure Modulate the Apparent pKa of Ionizable Lipid Nanoparticles","authors":"Anastasiia Priss,&nbsp;Olha Lytvynenko,&nbsp;Vaclav Vanek,&nbsp;Frantisek Sedlak,&nbsp;Klara Grantz Saskova,&nbsp;Petr Cigler","doi":"10.1021/acs.bioconjchem.6c00177","DOIUrl":"https://doi.org/10.1021/acs.bioconjchem.6c00177","url":null,"abstract":"<p>Ionizable lipid nanoparticles(LNPs) underpin today’sRNAmedicines by shielding nucleic acids in the bloodstream and transforminginto membrane-active cationic nanoparticles inside acidifying endosomes.This behavior critically depends on the apparent p<em>K</em>_a of LNPs, which can be tuned by altering the chemistryof lipids/lipidoids and the ratios of helper lipids. However, formulatorstypically assume that different RNA payloads exert identical effectson LNP ionization. In this study, we challenge this assumption andquantify how RNA modulates LNP p<em>K</em>_a. LNPformulations with different ionizable lipidoids (SM-102, cKK-E12,ALC-0315, 306O_i10, XMAN6, and C12-200) were used to encapsulatevarious RNA cargos, which ranged from 21-nt to 4.5-kb mRNAs. Apparentp<em>K</em>_a values were determined using a TNSfluorescence titration assay. RNA payload size impacted the apparentp<em>K</em>_a of the LNPs by 0.1–0.5 pH units,the direction and magnitude of the change being dependent on the structureof the ionizable lipidoid. Moreover, same-length 21-nt siRNA and miRNAcargos produced a 0.15 pH-unit difference in XMAN6 LNPs, indicatingthat RNA structural features can modulate apparent p<em>K</em>_a independently of payload size. With the monoamine lipidoidSM-102, short RNAs lowered the apparent p<em>K</em>_a relative to mRNA-loaded particles, whereas the multiamine lipidoidscKK-E12 and XMAN6 exhibited a monotonic decrease in apparent p<em>K</em>_a as RNA length increased, plateauing at ∼1.9kb. The most pronounced discrepancies between apparent p<em>K</em>_a values of lipidoid particles and corresponding LNPs(of ≤0.5 pH units) were observed with the triamine lipidoidXMAN6, pointing to a role of amino group multiplicity in the modulationof apparent p<em>K</em>_a. These findings demonstratethat RNA payload size is an underappreciated lever for tuning LNPionization behavior and that considering RNA payload size when conductinglipid/lipidoid library screens could enhance the development of futureRNA-based therapeutics.</p>","PeriodicalId":29,"journal":{"name":"Bioconjugate Chemistry","volume":"37 8","pages":"1537–1544"},"PeriodicalIF":4.5,"publicationDate":"2026-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148769848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}