Malaria remains a global health crisis, particularly in poverty-stricken regions where effective drug administration is challenging. To address this, we propose an innovative drug delivery system using injectable hydrogels that provide sustained release of antimalarial drugs through a single intradermal injection. These hydrogels incorporate lipid nanoparticles (LNPs) based on natural lipid components—carnauba wax and red palm oil—which enable intracellular drug release. The LNPs are embedded in a biocompatible glycosaminoglycan-poly(ethylene oxide) hydrogel, forming an in situ self-assembling scaffold via Michael-type addition reaction.
A key challenge in this system is understanding LNP stability, distribution, morphology, drug encapsulation, and release dynamics from the hydrogel matrix. To address these, we employ an advanced analytical strategy, integrating Dynamic Light Scattering, Nanoparticle Tracking Analysis , Cryo-TEM, Small- and Wide-Angle X-ray Scattering (SAXS/WAXS), and Asymmetric Flow Field-Flow Fractionation (AF4). Notably, the online coupling of AF4 with SAXS provides unique insights into size distributions below 10 nm. Additionally, online UV-Vis and fluorescence detection enable detailed drug quantification and localization within the nanoparticles. A precisely designed separation approach answers the question of the particle release from the hydrogel matrix.
This comprehensive analysis of nanoparticle behavior within injectable hydrogels ist enhanced by studies on biocompatibility and efficacy for human skin applications. By offering a patient-friendly, single-dose treatment with potential to both cure malaria and block parasite transmission to mosquitoes, this study paves the way for a transformative malaria treatment strategy with real-world application potential.

Block copolymers are of great interest in macromolecular chemistry and are used in various applications. For example, polymers can be used to stabilise polymer-lipid particles which important tools for studying membrane proteins in various biotechnological applications.1 Characterisation of these block copolymers and polymer/lipid complexes can still be challenging. Nuclear magnetic resonance (NMR) spectroscopy has been widely used to analyse polymer and biological samples.2 Pulsed-field gradient NMR has become a routine technique for measurement of self-diffusion coefficients of molecules.3 Typically, diffusion ordered spectroscopy (DOSY) is used to analyse mixtures of small molecules and oligomeric states of biomolecules.4 However, the use of DOSY in polymer science is less routine. Diffusion coefficients are an important starting point for understanding the chemistry of a system and can yield information such as molecular size. This talk will explore the use of NMR tools to better understand block copolymers and polymer/lipid systems.

The most important contributing factors to the catalytic activity and specificity of single chain nanoparticles (SCNPs) are their size and shape, as these can be linked to the location and the accessibility of the catalytic center. SNCPs are promising candidates for catalysis applications and biomimetic materials, yet predicting their three-dimensional structure, position and accessibility of the catalytic center using conventional methods is highly challenging. The mass, dispersity, and nature of the monomeric units are the only information provided by most analytical methods. Herein, we combine ion mobility spectrometry mass spectrometry with molecular dynamics simulations to characterize the folding and the three-dimensional structure of polystyrene-based, gold containing, single chain nanoparticles. We find that the folding process of the copolymer is initiated by π-π stacking interactions between adjacent styrene units with the possible formation of H-bond helping stabilising the final 3D structure of the folded SNCP. The chloride atom of the catalytically active Au-Cl unit can form strong hydrogen bonds with the protonated 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) end group, while a weaker H-bond can also be formed between the protonated TEMPO end group and the hydroxyl group of styrene-CH2-OH monomers. By allowing a detailed characterization of size, shape and position of the catalytic centers of a SCNP, our joint experimental/theoretical approach allows establishing a precise structure-activity relationship for SNCPs.

The development of new smart materials introduces advanced functionalities for applications in cryptography and physical information storage. [1] Smart materials, such as Liquid Crystalline Networks (LCNs), offer stimuli-induced reversible changes in several properties (optical, mechanical, etc.) by the LC monomer composition. This can be combined with lithographic techniques like Two-Photon Direct Laser Writing (TP-DLW) offering a fascinated alternative to produce 3D micro-tags for physical information storage.[2] Combining LCNs with TP-DLW (Figure 1) responsive 3D microstructures for secure information encoding were demonstrated. These structures act as covert tags for physical and optical encryption, in which the opto-mechanical "invisible ink" hides information and reveal it only under specific stimulation.[3] To enhance the information content of the secure micro-tags, we are now studying unique 3D printed diffractive optical elements and phase masks. Such structures, illuminated by laser light, provide an easy reading mechanism in the far field while their un-clonability introduces an additional degree of security and product identification. We demonstrate that responsive materials introduce novel mechanisms for anticounterfeiting and we believe that their employment at the microscale can foster new solutions for optical memories and micro-optomechanical systems.
The authors acknowledge the funding project PHOTAG financed by Italian Ministry of University and Research (MUR) within the action" Missione 4 Istruzione e ricerca – Componente 2 “Dalla ricerca all’impresa” Investimento 1.1 Fondo per il Programma Nazionale di Ricerca e Progetti di Rilevante Interesse Nazionale (PRIN)” del PNRR – Finanziato dall’Unione Europea – NextGenerationEU".

The dispersity (Ð) of polymers is one of the most important parameters when characterizing polymers. The gold standard for dispersity determination is size exclusion chromatography (SEC). Despite its wide spread use, dispersity can easily be misinterpreted. Its main issue stems from the molar mass dependence of dispersity , i.e., two polymers might have the same dispersity but different molar masses represent a different broadness of a distribution since they present a different standard variation around their mean. In our work, we synthesised 26 different polymers (1.1 < Ð < 3.7) to correlate the dispersity measurements of SEC with molar mass distribution determination through diffusion-ordered NMR spectroscopy (DOSY). Firstly, we could demonstrate how a broad range of dispersity influences the DOSY calibration correlation (log D vs. log M) and compared values of Mw, Mn and Ð between both techniques. Interestingly, using the standard deviation (σ) and coefficient of variation (σ/Mn) of the distributions allows for a much better correlation between both methods, underpinning the usefulness of using σ more regularly in polymer characterization.

The potential of benchtop nuclear magnetic resonance (NMR) spectrometer in polymer analytics is demonstrated using specialized benchtop NMR spectrometers operating at ¹H Larmor frequencies of 60, 80, and 90 MHz. Applications include the analysis of pyrolysis oils of thermally recycled polymers, online hyphenation to HPLC with 1D and 2D NMR detection, and molecular weight determination using diffusion-ordered spectroscopy (DOSY). While benchtop NMR spectrometers offer significant advantages over high-field NMR (e.g. no liquid N₂, He cooling), low sensitivity remains a challenge. Therefore, our focus is on enhancing sensitivity.
For pyrolysis oil analysis, NMR acquisition parameters were optimized. Using the 90 MHz spectrometer, aldehyde protons at concentrations as low as 10 ppm content could be detected within 20 seconds.
In HPLC-NMR hyphenation, size-exclusion chromatography (SEC) and liquid-adsorption chromatography (LAC) modes were applied. [1-4] Optimization encompassed NMR detection, chromatographic separation, flow cell geometries, and post-acquisition data processing. Applications include monomer composition analysis as a function of molecular weight for copolymers using SEC-60 MHz NMR hyphenation and analysis of low molecular weight preservatives with LAC-80 MHz NMR hyphenation. Due to the overall optimization, an increase in sensitivity by a factor 1000 was achieved with detection limits for HPLC-1D NMR hyphenation (80 MHz) of <0.040 g/L injection concentration for single protons.
Additionally, DOSY using the 90 MHz spectrometer enabled determination of monomer composition as a function of molecular weight for copolymers ranging from 1–1000 kg/mol in under 12 minutes. [5] These results underscore the versatility of benchtop NMR for advanced polymer analysis.