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This document is the Accepted Manuscript version of a Published Work that appeared in final form in The journal of physical chemistry letters, copyright © 2023 The Authors. Published by American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/full/10.1021/acs.jpclett.3c00643, Poly(amidoamine) (PAMAM) dendrimers are used to modify the interface of metal-semiconductor junctions. The large number of protonated amines contributes to the formation of a dipole layer, which finally serves to form electron-selective contacts in silicon heterojunction solar cells. By modification of the work function of the contacts, the addition of the PAMAM dendrimer interlayer quenches Fermi level pinning, thus creating an ohmic contact between the metal and the semiconductor. This is supported by the observation of a low contact resistivity of 4.5 mO cm2 , the shift in work function, and the n-type behavior of PAMAM dendrimer films on the surface of crystalline silicon. A silicon heterojunction solar cell containing the PAMAM dendrimer interlayer is presented, which achieved a power conversion efficiency of 14.5%, an increase of 8.3% over the reference device without the dipole interlayer., This research has been supported by the Spanish government through Grants PID2019-109215RB-C41, PID2019- 109215RB-C43, and PID2020-116719RB-C41 funded by MCIN/AEI/10.13039/501100011033. Thomas Tom acknowledges the support of the Secretaria d’Universitats i Recerca de la Generalitat de Catalunya and the European Social Fund (2019 FI_B 00456). In addition, the authors thank the technical staff from Barcelona Research Center in Multiscale Science and Engineering from the Universitat Politecnica ̀ de Catalunya for their expertise and helpful discussions over the XPS results, Dr. Oriol Arteaga from the Universitat de Barcelona for the ellipsometry measurements, and Guillaume Sauthier from the Catalan Institute of Nanoscience and Nanotechnology for his contribution to UPS measurements and their discussion., Peer Reviewed, Postprint (published version)

application/pdf, Bioconjugate Chemistry. 2021, 32 (3), P.563-571

Dendronized polyethers give rise to columnar LC structures which can successfully act as cation transport materials. Therefore, we prepared two different materials, based on Poly(epichlorohydrin-co-ethylene oxide) (PECH-co-EO) grafted with methyl 3,4,5-tris[4-(n-dodecan-1-yloxy)benzyloxy] benzoate, containing 20% or 40% modified units, respectively. The obtained polymers were characterized by differential scanning calorimetry (DSC), X-ray diffraction and optical microscopy between crossed polars (POM) and compared to the unmodified PECH-co-EO. In order to reach efficient transport properties, homeotropically oriented membranes were prepared by a fine-tuned thermal annealing treatment and were subsequently investigated by dynamic mechanical thermal analysis (DMTA) and dielectric thermal analysis (DETA). We found that the presence of the dendrons induces a main chain partial crystallization of the polyether chain and coherently increases the polymer Tg. This effect is more evident in the oriented membranes. As for copolymer orientation upon annealing, the cooling rate and the annealing temperature were the most crucial factors. DMTA and DETA confirmed that grafting with the dendron strongly hinders copolymer motions, but did not show great differences between unoriented and oriented membranes, regardless of the amount of dendrons.

CO preferential oxidation (PROX) is an effective method to clean reformate H2 streams to feed low-temperature fuel cells. In this work, the PROX and CO oxidation reactions were studied on preformed Au nanoparticles (NPs) supported on TiO2 anatase. Preformed Au NPs were obtained from gold cores stabilized by dodecanethiols or trimethylsilane-dendrons. A well-controlled size of ca. 2.6 nm and narrow size distributions were achieved by this procedure. The catalysts were characterized by high-resolution transmission electron microscopy and ex situ and in situ X-ray photoelectron spectroscopy (XPS). The XPS results showed that the preformed Au NPs exhibited high thermal stability. The different ligand-derived Au catalysts, as well as a conventional gold catalyst for comparison purposes, were loaded onto cordierite supports with 400 cells per square inch. The activity and selectivity of the samples were evaluated for various operation conditions. The catalyst prepared using dodecanethiol-capped Au NPs showed the best performance. In fact, CO conversions of up to 70% at 40% CO2 selectivity and 90% O2 conversion were observed operating at 363 K in H2-rich atmospheres. The performance of the best catalysts was subsequently tested on stainless steel microreactors. A 500-hour stability test was carried out under a real post-reformate stream, including 18 vol.% CO2 and 29 vol.% H2O. A mean CO conversion of ca. 24% was measured for the whole test operating at 453 K and a gas hourly space velocity (GHSV) of 1.3 × 104 h-1. These results reveal our dodecanethiol- and carbosilane-derived Au catalysts as extremely promising candidates to conduct a PROX reaction while avoiding deactivation, which is one of the major drawbacks of Au/TiO2 catalysts., Peer Reviewed, Postprint (published version)

Práce je věnována vývoji elektrochemického imunosenzoru pro průkaz bakteriálních buněk Campylobacter jejuni. Systém využívá primární protilátky, imobilizované na magnetických částicích, pro izolaci bakteriálních buněk, a sekundární protilátky značené kvantovými tečkami (QDs), které umožňují elektrochemickou detekci. Pro stanovení byly použity jednorázové tištěné tříelektrodové senzory umožňující analýzu malých objemů. Detekční metodou byla square wave anodická, resp. katodická rozpouštěcí voltametrie., The work is devoted to the development of an electrochemical immunosensor for the detection of Campylobacter jejuni. The system uses primary antibodies, immobilized on magnetic particles, to isolate bacterial cells, and secondary antibodies labeled with quantum dots (QDs), which allow electrochemical detection. Disposable screen-printed three-electrode sensors enabling small volume analysis were used for the determination. The detection method was square wave anodic/cathodic dissolution voltammetry., Fakulta chemicko-technologická, Studentka seznámila členy zkušební komise s obsahem své diplomové práce, poté byla seznámena s posudky vedoucího a oponenta diplomové práce. Studentka odpověděla na otázky oponenta diplomové práce a členů zkušební komise., Dokončená práce s úspěšnou obhajobou

Tato diplomová práce je zaměřena na přípravu elektrochemického imunosenzoru pro detekci bakteriálních buněk, konkrétně Salmonella spp., a Campylobacter jejuni. Systém je založený na principu heterogenní imunoanalýzy, který využívá primární protilátky pro izolaci bakteriálních buněk, imobilizované na magnetickém nosiči, a sekundární protilátky, značené vybranými nanočásticemi, které umožňují následnou elektrochemickou detekci. Nejprve byly optimalizovány postupy pro přípravu magnetického nosiče pro izolaci bakteriálních buněk ze vzorku. Pro značení protilátek pak byly zvoleny CdTe nebo PbS kvantové tečky (QDs) kombinované se silika nanočásticemi. Kromě kvantových teček byly testovány i zlaté nanočástice (AuNPs) a také polymerní dendrony, jako alternativa silika nanočástic. Stanovení probíhalo na tištěných tříelektrodových senzorech s uhlíkovou pracovní elektrodou pomocí square wave anodické, resp. katodické rozpouštěcí voltametrie jako detekční metody., This diploma thesis is focused on preparation of electrochemical immunosensor for detection of whole bacterial cells, specifically Salmonella spp., and Campylobacter jejuni. The system is based on the principle of heterogeneous immunoassay that uses primary antibodies immobilized on a magnetic carrier and secondary labelled antibodies which enable subsequent electrochemical detection. Firstly, procedures for preparing a magnetic carrier for isolation of bacterial cells from the sample were optimized. CdTe or PbS quantum dots (QDs) combined with silica nanoparticles were then selected for antibody labelling. Next to QDs, gold nanoparticles (AuNPs) were tested, and also polymer dendrons as an alternative to silica nanoparticles. Electrochemical detection was carried out on screen-printed three-electrode sensors with carbon working electrode and square wave anodic or cathodic stripping voltammetry as detection method., Fakulta chemicko-technologická, Studentka seznámila členy zkušební komise s obsahem své diplomové práce, poté byla seznámena s posudky vedoucího a oponenta diplomové práce. Studentka odpověděla na otázky oponenta diplomové práce a členů zkušební komise., Dokončená práce s úspěšnou obhajobou

Glycoconjugates, such as glycolipids and glycoproteins, play an important role in health and disease. The synthesis and biological evaluation of these glycoconjugates allows for the development of novel carbohydrate-based therapeutics and analytical tools. Traditionally, the conjugation of glycans to other substrates required the installment of an anomeric linker during the total synthesis of the glycan, however, this strategy does not allow for the conjugation of naturally isolated glycans. To address this concern, glycan conjugation methodologies without the need for protecting groups have been developed, including the use of oxyamine conjugation methodologies. In particular, the synthesis of a variety of novel bi-functional oxyamine linkers enabled the rapid assembly of various types of glycoconjugates, including fluorescent- and biotinylated-glycans, glycoproteins and multivalent glycodendrons. The multivalent presentation of glycans to cell surface lectins is often required to induce a measurable biological response. This multivalent binding can be achieved by the presentation of glycans on dendrons as these ‘glycodendrons’ have increased affinity for their corresponding lectin compared to monovalent glycans. Moreover, these glycodendrons have several advantages, including high synthetic control, low cytotoxicity and in addition can be derivatised with molecular probes of choice, which can aid in the biological evaluation of these glycoconjugates. Accordingly, novel biotinylated and fluorescent dendrons were synthesised from a highly convergent second generation dendron core scaffold. These functionalised dendrons then allow for the nonavalent conjugation of carbohydrates, such as Lewis antigens, for their biological evaluation in the selective targeting of lectins. Lewis antigens play an important role in host cell recognition, but these glycans are also involved in disease, such as in cancer metastasis and HIV-infection. The synthesis of Lewis antigens allows

Glycoconjugates, such as glycolipids and glycoproteins, play an important role in health and disease. The synthesis and biological evaluation of these glycoconjugates allows for the development of novel carbohydrate-based therapeutics and analytical tools. Traditionally, the conjugation of glycans to other substrates required the installment of an anomeric linker during the total synthesis of the glycan, however, this strategy does not allow for the conjugation of naturally isolated glycans. To address this concern, glycan conjugation methodologies without the need for protecting groups have been developed, including the use of oxyamine conjugation methodologies. In particular, the synthesis of a variety of novel bi-functional oxyamine linkers enabled the rapid assembly of various types of glycoconjugates, including fluorescent- and biotinylated-glycans, glycoproteins and multivalent glycodendrons. The multivalent presentation of glycans to cell surface lectins is often required to induce a measurable biological response. This multivalent binding can be achieved by the presentation of glycans on dendrons as these ‘glycodendrons’ have increased affinity for their corresponding lectin compared to monovalent glycans. Moreover, these glycodendrons have several advantages, including high synthetic control, low cytotoxicity and in addition can be derivatised with molecular probes of choice, which can aid in the biological evaluation of these glycoconjugates. Accordingly, novel biotinylated and fluorescent dendrons were synthesised from a highly convergent second generation dendron core scaffold. These functionalised dendrons then allow for the nonavalent conjugation of carbohydrates, such as Lewis antigens, for their biological evaluation in the selective targeting of lectins. Lewis antigens play an important role in host cell recognition, but these glycans are also involved in disease, such as in cancer metastasis and HIV-infection. The synthesis of Lewis antigens allows

The current study presents a library of honeycomb-like patterned surfaces developed from a variety of different water-soluble amphiphilic dendrons. When compared to commercial surfactants, the dendrons produce a wide variety of porous surfaces due to their well-defined branched structure. Different functionalities and generations of dendrons have been studied. A singular hierarchical distribution of the dendrons, forming small nanoparticles (micelles) only at the inner edges of the holes (coffee stain effect) is observed. Once the surfaces are fabricated, these dendrons can be easily recovered via simple aqueous washing. After this treatment, the surfaces exhibit a high hydrophobic character (up to 140°) due to the high porosity. This behavior can be described by the Cassie-Baxter model.

A series of (cholesteryl) 2,5-dibromobenzoate dendrons consisting of a first generation (G1=1 (cholesteryl) 4-benzoate), second generation (G2=2 (cholesteryl)s 4-benzoates) and third eneration (G3=4 (cholesteryl)s 4-benzoates) were synthesized step-by-step by the convergence approach. The 2,5-dibromo G1, G2 and G3 synthesized dendrons were subjected to co-polymerization with (butyl) 2,5-diethynyl benzoate by the Sonogashira cross-coupling reaction to afford rigid rod-like vermicular dendrimers of the phenyleneethynylene type, which resulted be very soluble in non-polar solvents such as CHCl3, THF, toluene. Their chemical structures were analyzed by 1H, APT, DEPT-135, 13C NMR, however for their correct proton-carbon assignation, it was necessary to carry out 2D-HETCOR correlations. The thermal properties studied by DSC, TGA and Polarized light microscopy showed that all of the (cholesteryl) 2,5-dibromobenzoate dendrons exhibited a mesomorphic behavior: Crystal (double arrow) Smectic C (or Nematic) (double arrow) Isotropic transitions, where mesophases are presented in a very short temperature range. In what concerns to the copolymers, in spite of that they do not exhibit any know texture reported in the literature, however they seem to exhibit Smectic C and/or Nematic mesophases, nonetheless the study of X-ray at small angle is necessary in order to better determine their real supramolecular order of the mesophase(s)., The original document contains color images.

The combination of dendrons and high temperature acrylate polymerization represents a viable route to form dendronized macromonomers. Dendronized acrylates based on 2,2-bis(hydroxymethyl)propionic acid (bis-MPA) were synthesized using dendrimer synthesis and click chemistry (copper catalyzed azide alkyne cycloaddition (CuAAC)). The synthesis was carried out up to the 3rd generation and with a carbon spacer length of 6 or 9 between the acrylic function and the dendron core. These dendronized acrylates were subjected to auto-initiated high temperature acrylate polymerization. The polymerization was performed at 140 °C in a 5 wt% solution of hexyl acetate with a 2,2'-azobis(isobutyronitrile) (AIBN) concentration of 5 x 10-3 g mol-1. The vinyl terminated polymers were in-depth characterized via size exclusion chromatography (SEC) and size exclusion chromatography coupled to electrospray ionization mass spectrometry (SEC-ESI-MS) to assess the generated product spectrum and the efficiency of the process. The achievable number average molecular weight, Mn, was between 1700 and 4400 g mol -1. The degree of polymerization, DPn, decreases with increasing generations of the dendronized acrylates from 6.3 to 3.4. The purity of vinyl terminated oligomers containing a geminal double bond is up to 83%, with the dendronized acrylates of the 1st generation providing the best result. Moderate deprotection of the acetonide groups occurred spontaneously during the macromonomer formation process and reached its maximum at generation 3. © The Royal Society of Chemistry 2011.

L’1,2-dicarba-closo-dodecaborà, l’o-carborà, és un clúster icosaèdric format per deu vèrtexs de bora–hidrogen i dos vèrtexs de carboni–hidrogen en posició adjacent. Aquesta molècula és químicament molt versàtil, ja que presenta una reactivitat diferenciada segons el tipus de vèrtex, la qual cosa en permet la derivatització en funció de l’aplicació mèdica desitjada. Al nostre grup de recerca, tenim una gran experiència en reaccions de substitució electrofílica sobre els àtoms de bor, sobretot per tal d’obtenir derivats B-iodats de l’o-carborà quecontinguin un elevat nombre d’àtoms de iode per molècula. Aquesta condició els converteix en bons candidats per ser usats com a agents de contrast opacs als raigs X en ciments ossis polimèrics de metilmetacrilat. Els enllaços de bor–iode d’aquests carborans poden ser posteriorment derivatitzats amb diferents grups orgànics funcionals, tot formant nous vèrtex de bor–carboni i obtenint, així, molècules útils com a nuclis d’estructures de tipus dendró. El creixement dendrimèric d’aquests nuclis es du a terme mitjançant reaccions d’acoblament amb altres clústers de carborà funcionalitzats, tot obtenint molècules ambun elevat contingut en àtoms de bor, molt útils com a agentsanticancerosos en la tècnica BNCT (Boron Neutron CaptureTherapy).Paraules clau: carborans, iode, agents de contrast, raigs X,dendrons, captura de neutrons, BNCT, EINS., The 1,2-dicarba-closo-dodecaborane, o-carborane, is an icosahedral cluster consisting of ten boron-hydrogen vertices and two carbon-hydrogen adjacent vertices. This molecule is chemically versatile, has a differential reactivity depending on the type of vertex, and this enables the functionalization according to the desired medical application. Our research group has extensive experience in electrophilic substitution reactions on the boron atoms, especially to obtain boron-iodinated carborane derivatives, which contain a largenumber of iodine atoms per molecule. This condition makes them good candidates for use as X-ray contrast agents in methyl methacrylate bone cements. These boron-iodine bonds may be subsequently functionalized with various organic functional groups forming new boron-carbon vertices and producing useful molecules as dendron nuclei. The growth of these dendrimeric cores is carried out by coupling reactions with other functionalized carboranes yielding molecules with high boron content, useful as anticancer agents in BNCT (Boron Neutron Capture Therapy).Keywords: carboranes, iodine, contrast agent, X-ray, dendrons, neutron capture, BNCT, EINS.

L’1,2-dicarba-closo-dodecaborà, l’o-carborà, és un clúster icosaèdric format per deu vèrtexs de bora–hidrogen i dos vèrtexs de carboni–hidrogen en posició adjacent. Aquesta molècula és químicament molt versàtil, ja que presenta una reactivitat diferenciada segons el tipus de vèrtex, la qual cosa en permet la derivatització en funció de l’aplicació mèdica desitjada. Al nostre grup de recerca, tenim una gran experiència en reaccions de substitució electrofílica sobre els àtoms de bor, sobretot per tal d’obtenir derivats B-iodats de l’o-carborà quecontinguin un elevat nombre d’àtoms de iode per molècula. Aquesta condició els converteix en bons candidats per ser usats com a agents de contrast opacs als raigs X en ciments ossis polimèrics de metilmetacrilat. Els enllaços de bor–iode d’aquests carborans poden ser posteriorment derivatitzats amb diferents grups orgànics funcionals, tot formant nous vèrtex de bor–carboni i obtenint, així, molècules útils com a nuclis d’estructures de tipus dendró. El creixement dendrimèric d’aquests nuclis es du a terme mitjançant reaccions d’acoblament amb altres clústers de carborà funcionalitzats, tot obtenint molècules ambun elevat contingut en àtoms de bor, molt útils com a agentsanticancerosos en la tècnica BNCT (Boron Neutron CaptureTherapy).Paraules clau: carborans, iode, agents de contrast, raigs X,dendrons, captura de neutrons, BNCT, EINS., The 1,2-dicarba-closo-dodecaborane, o-carborane, is an icosahedral cluster consisting of ten boron-hydrogen vertices and two carbon-hydrogen adjacent vertices. This molecule is chemically versatile, has a differential reactivity depending on the type of vertex, and this enables the functionalization according to the desired medical application. Our research group has extensive experience in electrophilic substitution reactions on the boron atoms, especially to obtain boron-iodinated carborane derivatives, which contain a largenumber of iodine atoms per molecule. This condition makes them good candidates for use as X-ray contrast agents in methyl methacrylate bone cements. These boron-iodine bonds may be subsequently functionalized with various organic functional groups forming new boron-carbon vertices and producing useful molecules as dendron nuclei. The growth of these dendrimeric cores is carried out by coupling reactions with other functionalized carboranes yielding molecules with high boron content, useful as anticancer agents in BNCT (Boron Neutron Capture Therapy).Keywords: carboranes, iodine, contrast agent, X-ray, dendrons, neutron capture, BNCT, EINS.

By taking advantage of the orthogonal nature of thiol-ene coupling and anhydride based esterification reactions, a facile and chemoselective strategy to dendritic macromolecules has been developed The ability to interchange growth steps based on thiol-ene and anhydride chemistry allows the synthesis of fifth-generation dendrimers in only five steps and under benign reaction conditions In addition, the presented coupling chemistries eliminate the traditional need for protection/deprotection steps and afford dendrimers in high yield and purity The modularity of this strategy coupled with the latent reactivity of the alkene/hydroxyl chain ends was demonstrated by using different cores (alkene and hydroxyl functional), various AB(2) and CD2 monomers and a range of chain end groups As a result, three dendritic libraries were prepared which exhibited tunability of both the chemical functionality and physical properties including the fabrication of PEG hydrogels., QC 20110208

The synthesis of thiophene-containing second (G2) and third generation (G3) dendronized macromonomers with methacrylate polymerizable units as well as their corresponding dendronized polymers is reported. The dendrons are prepared from branched thiophene oligomers and are decorated with straight alkyl chains for solubility reasons. The polymerization reactions were done with AIBN as initiator and the polymers were characterized by NMR spectroscopy, elemental analysis and GPC. Molar masses are in the range of 2.2-5.4 × 105 g mol-1 (G2) and 1.3-3.0 × 104 g mol-1 (G3) for different runs. These polymers are investigated by cyclic voltammetry and optical spectroscopy.

The high fidelity and efficiency of Click chemistry are exploited in the synthesis of a library of chain end functionalized dendritic macromolecules. In this example, the selectivity of the Cu-catalyzed [3 + 2 pi] cycloaddition reaction of azides with terminal acetylenes, coupled with mild reaction conditions, permits unprecedented functional group tolerance during the derivatization of dendrimeric and hyperbranched scaffolds. The resulting dendritic libraries are structurally diverse, encompassing a variety of backbones/surface functional groups, and are prepared in almost quantitative yields under very mild conditions. The robust and simple nature of this procedure, combined with its applicability to many aspects of polymer synthesis and materials chemistry, demonstrates an evolving synergy between advanced organic chemistry and functional materials., QC 20100525

A series of different dendrons for the encapsulation of 99mTc and 188Re have been synthesised, "3+1" mixed ligand 99mTc complexes with dendritic polyether thiols as monodendate ligands have been prepared. Challenge experiments with glutathione showed a remarkable enhancement of stability with increasing number of dendron generation. To achieve better solubility behaviour oligoethyleneoxy- and sugar-substituted dendrons are developed. In this case 2-aminobenzenethiol is introduced as chelating unit. Molecular modeling calculations point to an almost complete shielding of the radionuclide by use of second generation dendrons.

A series of different dendrons for the encapsulation of 99mTc and 188Re have been synthesised, "3+1" mixed ligand 99mTc complexes with dendritic polyether thiols as monodendate ligands have been prepared. Challenge experiments with glutathione showed a remarkable enhancement of stability with increasing number of dendron generation. To achieve better solubility behaviour oligoethyleneoxy- and sugar-substituted dendrons are developed. In this case 2-aminobenzenethiol is introduced as chelating unit. Molecular modeling calculations point to an almost complete shielding of the radionuclide by use of second generation dendrons.

A series of different dendrons for the encapsulation of 99mTc and 188Re have been synthesised, "3+1" mixed ligand 99mTc complexes with dendritic polyether thiols as monodendate ligands have been prepared. Challenge experiments with glutathione showed a remarkable enhancement of stability with increasing number of dendron generation. To achieve better solubility behaviour oligoethyleneoxy- and sugar-substituted dendrons are developed. In this case 2-aminobenzenethiol is introduced as chelating unit. Molecular modeling calculations point to an almost complete shielding of the radionuclide by use of second generation dendrons.

We have synthesized two new chromophore series whose bipolaron absorptions are in the spectral region 600-900 nm, an area of extreme interest for eye protection from laser attack. These chromophore series were derivatized for attachment to 3,5 dihydroxybenzyl alcohol to form dendrons, which were then attached to a core molecule, bis-phenol A, to form G-O dendrimers. We were also successful in preparing several dendrimers based on bis-(diphenylamino)stilbene repeat units by divergent methodology. These new dendrimers not only form highly absorbing charge states, but also display very large two photon absorption cross-sections. When the dendrimers are irradiated in the presence of strong electron acceptors, such as fullerene, photoinduced absorption occurs, and highly absorbing transient species are formed. In solution these photoinduced species appear to be polaronic rather than bipolaronic. These results offer the possibility that either polaronic radical-cations or bipolaronic dications might be accessible by photoinduced electron transfer processes. When these reverse saturable absorption processes occur in the same chromophores that have large two photon absorption, optical power limiting can observed from either or both mechanisms, depending on the excitation wavelength. Thus these new materials may be considered to be bimechanistic in an optical limiting sense.