Synthesis of Nanoscale Coordination Polymers in Femtoliter Reactors on Surfaces

Abstract

In the present work, AFM-assisted lithography was used to perform the synthesis of a coordination polymer inside femtoliter droplets deposited on surfaces. For this, solutions of the metal salt and the organic ligand were independently transferred to adjacent tips of the same AFM probe array and were sequentially delivered on the same position of the surface, creating femtoliter-sized reaction vessels where the coordination reaction and particle growth occurred. Alternatively, the two reagents were mixed in the cantilever array by loading an excess of the inks, and transferred to the surface immediately after, before the precipitation of the coordination polymer took place. The in situ synthesis allowed the reproducible obtaining of round-shaped coordination polymer nanostructures with control over their XY positioning on the surface, as characterized by microscopy and spectroscopy techniques.

pH‐Responsive Nanoscale Coordination Polymer for Efficient Drug Delivery and Real‐Time Release Monitoring

“…To address the aforementioned issues, we fabricated a simple but rational nanoscale coordination polymer to deliver doxorubicin (DOX) to tumor region and real‐time monitor of drug release. It is well documented that coordination polymers comprise well‐ordered structures in which organic ligands and metal ions are connected by coordination bonds . Herein, we chose Fe 3+ as the metal ion and polyphenol gallic acid (GA) as the ligand.…”

“Writing biochips”: high-resolution droplet-to-droplet manufacturing of analytical platforms

“…In addition, the authors estimated the average of the fluorescence mean intensity per surface area, which was equal to <6% deviation among the different printed droplets. The topic of femtoliter scale reactors was already investigated by Guardingo and coworkers 95 in 2016 by a model reaction involving the ligand 4-[2-(pyridine-4-yl)ethyl]benzene-1,2-diol with a cobalt salt to produce coordination polymer nanoparticles in spotted droplets, with good monodispersity and tunable dimensions (in the range 600–200 nm) by selecting the experimental conditions. Another DPN-based femtoliter chemistry study is the one from Navikas and coworkers 96 who instead engineered an ink formulation that combined eicosanethiol with the phospholipid 1,2-dioleoyl- sn-glycero -3-phosphocholine.…”

Switchable colloids, thin-films and interphases based on metal complexes with non-innocent ligands: the case of valence tautomerism and their applications

“…30 As a follow up of this work, we reported the in situ synthesis of VT coordination polymer particles confined into femtolitre droplet reactors. 31 For this, we followed two main approaches using the bi-component mixture (ligand and cobalt salt) detailed in Section 3 In the first of these approaches, two consecutive AFM tips of an array were differently functionalised with the ligand (tip 1) and the cobalt salt solutions (tip 2) of interest. Then, the coated tips were used to directly transfer these solutions to the same location of the surface, creating femtolitresized reaction vessels where the coordination reaction occurred.…”

“…Adapted from ref. 31. finally used to transfer the pattern in resistance to the underneath substrate (Fig.…”