Self-assembly of guanosine and deoxy-guanosine into hydrogels: monovalent cation guided modulation of gelation, morphology and self-healing properties

Adhikari, Bimalendu; Shah, Afzal; Kraatz, Heinz‐Bernhard

doi:10.1039/c4tb00702f

Cited by 80 publications

(69 citation statements)

References 88 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…S2). Notably there was an order of magnitude between G' and G" which is a characteristic of LMWGs 27 and a maximal G' value of 20 Pa, making it mechanically weaker than previous acyl cytidine derivatives 18 but a comparable magnitude to the guanosine and deoxy-guanosine gelators reported by Adhikari et al 9 The low G' value of this soft hydrogel is more indicative of entanglement of fibres than a crosslinked network. 28 Indeed, entanglement of fibres with transient crosslinks may be responsible for the most interesting behaviour of this N4-octanoyl-2ʹ-deoxycytidine gel as demonstrated by temperature profiling and time dependent-recovery tests.…”

Section: Please Do Not Adjust Marginsmentioning

confidence: 95%

“…Although this self-healing property has been extensively reported for polymeric systems, [13][14][15][16][17] there are fewer reports for LMW gels. [9][10][11] Pertinent examples are dipeptide gels (Fmoc-Leucinylglycine and Fmocphenylalaninylphenylalanine) which have been shown to recover after shear in similar experiments. Additional literature supports the mechanism for self-healing gels being associated Please do not adjust margins…”

Section: Please Do Not Adjust Marginsmentioning

confidence: 99%

“…the ability to reform after application of high shear. [9][10][11] This ability for recovery after high shear is particularly relevant for injectable gels sheared through a needle as following injection the gel would be required to revert back to its original state. Indeed the self-healing properties of LMWGs is uncommon 12 when compared to the reported self-healing of polymer hydrogels.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Developing a self-healing supramolecular nucleoside hydrogel

et al. 2016

View full text Add to dashboard Cite

A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription. Low molecular weight gelator hydrogels provide a viable alternative to traditional polymer based drug delivery platforms, owing to their tunable stability and in most cases inherent biocompatibility. Here we report the first self-healing nucleoside hydrogel using N4-octanoyl-2ʹ-deoxycytidine (0.5 % w/v) for drug delivery. The hydrogel's cross-linked nanofibrillar structure, was characterised using oscillatory rheology and confirmed using SEM and TEM imaging . The potential of this gel for drug delivery was explored in vitro using fluorescently labelled tracers. Cell viability assays were conducted using pancreatic cell lines which tolerated the gels well; whilst no adverse effects on the viability or proliferation of cells were observed for fibroblast cell lines.

show abstract

Section: Please Do Not Adjust Marginsmentioning

confidence: 95%

Section: Please Do Not Adjust Marginsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Developing a self-healing supramolecular nucleoside hydrogel

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Guanine and its derivatives have been mixed with monovalent metal ions to form gels based on quadruplex formation. [28][29][30][31] However, little has been done on adenine derivatives. Nanoparticles are the most common products.…”

mentioning

confidence: 99%

Self-healing metal-coordinated hydrogels using nucleotide ligands

et al. 2015

View full text Add to dashboard Cite

A supramolecular gel formed by Zn 2+ coordination with adenosine monophosphate (AMP) is reported. The adenine base, the monophosphate, and Zn 2+ are all important for gel formation. Mechanically disrupted gels can re-form upon centrifugation; applications of this gel for guest molecule entrapment are explored.Supramolecular gels have received considerable attention in recent years both as intriguing examples of self-assembly and as a means of creating smart materials.1-5 These gels are formed by noncovalent interactions to assemble supramolecular networks that trap solvent. 6Among the various types of supramolecular gels, those crosslinked by metal coordination are particular interesting. A few types of ligands have been developed for this purpose. For example, Craig and coworkers reported organopalladium−pyridine coordination. 16,17 Self-healing is a very interesting and useful feature of metal-coordinated gels; broken gel pieces can seal together with a mild mechanical force.Most of previously reported gels have to use specially designed ligands (e.g. incorporating a segment of PEG chain in addition to the metal ligand) to facilitate solvent trapping and gelation. Few reports are based on pure small molecule ligands. We reason that small molecule ligands will allow a higher metal density and thus may display different properties.Adenine, a purine nucleobase, is an important ligand in supramolecular chemistry. Adenine and its derivatives can form many complexes by coordination (with metal ions) and hydrogen bonding (with organic molecules). [18][19][20] With metal ions, it may form metalorganic frameworks, 21 and nanoparticles. [22][23][24][25] Recently, the gelation of adenine with tricarboxylic acid compounds was reported based on hydrogen bonding and π-π stacking. 26,27 We are interested in exploring whether it is possible to achieve gelation by metal coordination with adenine derivatives. Guanine and its derivatives have been mixed with monovalent metal ions to form gels based on quadruplex formation. 28-31 However, little has been done on adenine derivatives. Nanoparticles are the most common products. [22][23][24][25] Compared to nanoparticles, hydrogels are more attractive materials for making stimuli-responsible materials. [32][33][34][35][36][37][38][39] In this work, we communicate such an example, its property in guest molecule encapsulation, and healing.Since most previous work focused on adenine nucleobase and nucleoside as ligands, we started with nucleotide coordination in this work. Zn 2+ was chosen as the metal because it is a good Lewis acid that can be coordinated by a diverse range of ligands. In addition, it is a relatively biocompatible metal with low toxicity. We first studied the reaction between Zn 2+ and three kinds of nucleotides (AMP, GMP and CMP). TMP was not included since thymine has very weak coordination ability at neutral pH. Zn 2+ was respectively titrated into the solutions of AMP, GMP and CMP, and the UV-vis extinction at 550 nm was recorded. Since none of the products are c...

show abstract

“…8 More recent findings suggest that a similar K + deoxy-guanosine system forms much better gels with improved thixotropic properties compared to the guanosine counterparts. 9 Other gelators arise via modification of the ribose sugar, a strategy employed by Yun, 10 Godeau 11 and Moreau 12 and Xu 13,14 who recently reported enzyme labile gelating structures derived from existing known peptide gelators, functionalised at the 5'-position of the nucleoside guanosine and the nucleobase uridine. Another route less often taken is modification of the nucleobase at the 5-position, an example of which is that taken by Park 15 to derivatise ribo-and deoxyuridine.…”

Section: Introductionmentioning

confidence: 99%