Molecule-based Systems Research Articles

Highly Stable Self-Regenerating Organic Multi-Redox Systems derived from Bicyclic (Alkyl)(amino)carbenes (BICAACs).

An extended class of organic multi-redox systems was derived from bicyclic(alkyl)amino carbenes (BICAACs). The highly-conjugated system undergoes a total of 4 redox events spanning a 1.8 V redox range. These organic compounds exhibited four different stable redox states (dication, radical cation, neutral and radical anion), and all of them were characterized either by single crystal X-ray study and/or various spectroscopic studies. Three of the four redox states are stable to air and moisture. The availability of stable multiple redox states demonstrated promise towards their efficacy in the symmetric H-cell charge/discharge cycling. Among various redox states, the dication/neutral state works efficiently and continuously for 1500 cycles in 2e- charge/discharge process outside glovebox in commercially available DMF with minimum capacity loss (retaining nearly 90 % Coulombic efficiency). Surprisingly, the efficiency of the redox cycle was retained even if the system was exposed to air for 30 days when it slowly regenerated to the initial deep blue radical cation, and it exhibited another 100 charge/discharge cycles with a minimal capacity loss. Such a stable H-cell cycling ability is not well known among organic molecule-based systems.

Polymer-Entangled Spontaneous Pseudo-Planar Heterojunction for Constructing Efficient Flexible Organic Solar Cells.

Flexible organic solar cells (FOSCs) have attracted considerable attention from researchers as promising portable power sources for wearable electronic devices. However, insufficient power conversion efficiency (PCE), intrinsic stretchability, and mechanical stability of FOSCs remain severe obstacles to their application. Herein, an entangled strategy is proposed for the synergistic optimization of PCE and mechanical properties of FOSCs through green sequential printing combined with polymer-induced spontaneous gradient heterojunction phase separation morphology. Impressively, the toughened-pseudo-planar heterojunction (Toughened-PPHJ) film exhibits excellent tensile properties with a crack onset strain (COS) of 11.0%, twice that of the reference bulk heterojunction (BHJ) film (5.5%), which is among the highest values reported for the state-of-the-art polymer/small molecule-based systems. Finite element simulation of stress distribution during film bending confirms that Toughened-PPHJ film can release residual stress well. Therefore, this optimal device shows a high PCE (18.16%) with enhanced (short-circuit current density) JSC and suppressed energy loss, which is a significant improvement over the conventional BHJ device (16.99%). Finally, the 1cm2 flexible Toughened-PPHJ device retains more than 92% of its initial PCE (13.3%) after 1000 bending cycles. This work provides a feasible guiding idea for future flexible portable power supplies.

Lipoic Acid-Functionalized Hexanuclear Manganese(III) Nanomagnets Suitable for Surface Grafting.

Highly anisotropic single-molecule magnets (SMMs) have attracted much interest in the field of molecular magnetism because of their spin features and potential technological applications. Additionally, a great effort has been devoted to the functionalization of such molecule-based systems which are made with ligands containing functional groups suitable to connect SMMs to junction devices or to perform their grafting on surfaces of different substrates. We have synthesized and characterized two lipoic acid-functionalized and oxime-based Mn(III) compounds, of formula [Mn6(μ3-O)2(H2N-sao)6(lip)2(MeOH)6][Mn6(μ3-O)2(H2N-sao)6(cnph)2(MeOH)6]}·10MeOH (1) and [Mn6(μ3-O)2(H2N-sao)6(lip)2(EtOH)6]·EtOH·2H2O (2) [H2N-saoH2 = salicylamidoxime, lip = lipoate anion, cnph = 2-cyanophenolate anion]. Compound 1 crystallizes in the space group Pī of the triclinic system and 2 crystallizes in the space group C2/c of the monoclinic system. In the crystal, neighboring Mn6 entities are linked using non-coordinating solvent molecules, which are H-bonded to N atoms of -NH2 groups of amidoxime ligand. In addition, Hirshfeld surfaces of 1 and 2 were calculated to study the variety of intermolecular interactions and the different levels of importance that take place in their crystal lattice; this type of computed study is the first time performed on Mn6 complexes. The study of the magnetic properties of 1 and 2 through dc magnetic susceptibility measurements reveals the coexistence of ferromagnetic and antiferromagnetic exchange couplings between the Mn(III) metal ions in both compounds, the latter being the predominant magnetic interaction. A spin S = 4 value of the ground state was obtained using isotropic simulations of the experimental magnetic susceptibility data for both 1 and 2. Ac magnetic susceptibility measurements show features typical of slow relaxation of the magnetization in 1 and 2, which indicate that SMM behavior takes place in both compounds.

From an antiferromagnetic insulator to a strongly correlated metal in square-lattice MCl2(pyrazine)2 coordination solids

Electronic synergy between metal ions and organic linkers is a key to engineering molecule-based materials with a high electrical conductivity and, ultimately, metallicity. To enhance conductivity in metal-organic solids, chemists aim to bring the electrochemical potentials of the constituent metal ions and bridging organic ligands closer in a quest to obtain metal-d and ligand-π admixed frontier bands. Herein, we demonstrate the critical role of the metal ion in tuning the electronic ground state of such materials. While VCl2(pyrazine)2 is an electrical insulator, TiCl2(pyrazine)2 displays the highest room-temperature electronic conductivity (5.3 S cm–1) for any metal-organic solid involving octahedrally coordinated metal ions. Notably, TiCl2(pyrazine)2 exhibits Pauli paramagnetism consistent with the specific heat, supporting the existence of a Fermi liquid state (i.e., a correlated metal). This result widens perspectives for designing molecule-based systems with strong metal-ligand covalency and electronic correlations.

(Invited) Probing Charge Carrier Dynamics in Porphyrin-Based Bulk Heterojunction Thin Films with Time-Resolved Terahertz Spectroscopy

Organic photovoltaic (OPV) solar cells have attracted much attention in recent years because of the low production cost and ease of device fabrication. However, the power conversion efficiency is still low compared to the silicon and perovskite solar cells so that further research is necessary to improve their performance. In particular, understanding of the detailed mechanisms of charge carrier generation, recombination and carrier transport process is very important for developing design principles of new compounds for OPVs. Until now, polymer-based compounds have been widely used for p-type semiconductors. However, it is not easy to obtain information on how the microscopic structure of bulk heterojunction (BHJ) blend of donor and acceptor materials affect the charge carrier dynamics because one cannot easily control the molecular weight and conformational distributions of polymer compounds. On the other hand, small molecule-based semiconductors have several unique advantages such well-defined chemical structures, ease of purification and small batch-to-batch variations.Tetrabenzoporphyrin (BP) has been frequently used as a small-molecule organic semiconductor. Recently, Yamada and coworkers synthesized diketopyrrolopyrrole-linked tetrabenzoporphyrin (DPP-BP) conjugates that have linear alkyl groups on the DPP moieties whose chain length is defined as n, namely, Cn-DPP-BP (n=4, 6, 8, or 10). For DPP-BP based solar cells, they demonstrated that alkyl chain length affects the power conversion efficiency. Therefore, it is very interesting to see how the local BHJ structures of DPP-BP based thin films affect the initial step of the charge carrier dynamics because such studies are difficult to perform for polymer-based systems. We can take advantage of small molecule-based systems to study the relationship between the local structure and the charge carrier dynamics.In this work, we used time-resolved terahertz (THz) spectroscopy to investigate the charge carrier dynamics of DPP-BP BHJ thin films blended with [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM). Time-resolved THz spectroscopy is a unique method to quantify charge carrier mobility with very fast time resolution (less than picosecond). This spectroscopy reflects the charge carrier dynamics in the local spatial region because of the high-frequency nature of the THz electric field. We chose C4-DPP-BP:PC61BM and C10-DPP-BP:PC61BM thin films for the THz measurements. In the previous study, it was found that C4-DPP-BP molecule prefers to take a face-on geometry on the substrate. A grain size of the aggregates was around 100 nm or smaller which were measured by atomic force microscopy. In such a structure, one can expect that charge transport takes place very efficiently to the electrode. Actually, power conversion efficiency is 5.2 % which is highest among a series of DPP-BP chromophores. On the other hand, C10-DPP-BP adopts an edge-on geometry on the substrate and forms micrometer-sized aggregates. In this structure, molecular stacking is oriented perpendicular to the electrode so that power conversion efficiency decreases to 0.19%.In contrast to the other measurements, the THz spectroscopy has sensitivity to in-plane motion of the charge carriers with respect to the substrate, we expect to observe higher in-plane mobility of the charge carriers in the C10-DPP-BP:PC61BM BHJ films compared to C4-DPP-BP based films. In contrast to our intuitive expectation, we found that the product of the carrier mobility and the yield of the photo-generated charge carriers is similar to each other. We consider that the similarity of the charge carrier dynamics results from the high-frequency nature of the local mobility of the polarons because most of the polarons are confined in less than a 10-nm length scale. Furthermore, the lowest limit of the carrier mobility obtained from our results is about 1.0 cm2V-1s-1 when the quantum yield of the charge carrier generation is assumed to be unity. This value is much higher than those obtained by space-charge-limited current method. We expect that charge separation occurs very efficiently when the local mobility of the charge carrier is high.In this contribution, we will present importance of the local mobility of the charge carriers and difference of charge transport between short and long length scales in DPP-BP based solar cells.

Metallated Isoindigo-Porphyrin Covalent Organic Framework Photocatalyst with a Narrow Band Gap for Efficient CO2 Conversion.

Photocatalytic CO2 reduction into formate (HCOO-) has been widely studied with semiconductor and molecule-based systems, but it is rarely investigated with covalent organic frameworks (COFs). Herein, we report a novel donor-acceptor COF named Co-PI-COF composed of isoindigo and metallated porphyrin subunits that exhibits high catalytic efficiency (∼50 μmol formate g-1 h-1) at low-power visible-light irradiation and in the absence of rare metal cocatalysts. Density functional theory calculations and experimental diffuse-reflectance measurements are used to explain the origin of catalytic efficiency and the particularly low band gap (0.56 eV) in this material. The mechanism of photocatalysis is also studied experimentally and is found to involve electron transfer from the sacrificial agent to the excited Co-PI-COF. The observed high-efficiency conversion could be ascribed to the enhanced CO2 adsorption on the coordinatively unsaturated cobalt centers, the narrow band gap, and the efficient transfer of the charge originating from the postsynthetic metallation. It is anticipated that this study will pave the way toward the design of new simple and efficient catalysts for photocatalytic CO2 reduction into useful products.

Electrochemical Polymerization Provides a Function-Integrated System for Water Oxidation.

Water oxidation is a key reaction in natural and artificial photosynthesis. In nature, the reaction is efficiently catalyzed by a metal-complex-based catalyst surrounded by hole-transporting amino acid residues. However, in artificial systems, there is no example of a water oxidation system that has a catalytic center surrounded by hole transporters. Herein, we present a facile strategy to integrate catalytic centers and hole transporters in one system. Electrochemical polymerization of a metal-complex-based precursor afforded a polymer-based material (Poly-1). Poly-1 exhibited excellent hole-transporting ability and catalyzed water oxidation with high performance. It was also revealed that the catalytic activity was almost completely suppressed in the absence of the hole-transporting moieties. The present study provides a novel strategy for constructing efficient molecule-based systems for water oxidation.

Experimental and theoretical aspects of thermodynamic properties of quasi-1D and quasi-2D organic conductors and superconductors

We deal with thermodynamic features of organic conductors and superconductors where itinerant [Formula: see text]-electrons/holes released from organic molecules are playing essential roles for electronic properties. Since they are low-dimensional electronic systems with relatively soft lattice framework, they show variety of phenomena related to electron correlations and electron–lattice coupling. The drastic changes of conductive and magnetic properties owing to quantum features of [Formula: see text]-electrons can be induced by external perturbations such as magnetic/electric field, pressure, etc. It is especially emphasized that the possible mechanism and relation with other phenomena of the superconductivity in [Formula: see text]-electrons system remains to be one of the interesting research areas in fundamental condensed matter science. In this review paper, we consider several topics of organic conductors and superconductors from the standpoints of thermodynamic experiments, data analyses and theories performed up to now. Starting from the overall picture of the electronic states in charge transfer complexes, thermodynamic properties of the quasi-one-dimensional systems, quasi-two-dimensional systems and [Formula: see text]–d interacting systems are reviewed. The thermodynamic parameters of the superconductive compounds in them are compared and discussed. The relations with crystal structures, electronic states, phase diagram and other experiments are also discussed in comparison with these thermodynamic properties. The possible pairing symmetries in organic superconductors and some models are mentioned in the last part. This review deals with a wide scope of theoretical and experimental topics in superconductivity in molecule-based conductive systems.

Encoding Polymers with Information. A Supramolecular Porphyrin Approach

The amount of information trafficking internet nowadays is enormous and will increase further in the near future. It can be expected that in the next decennia the current technologies to store and process data will no longer suffice and that other strategies to handle information will have to be developed. One approach is to explore chemical routes, which nature has also followed during evolution: our brain can store and handle very large amounts of data and process them in a way silicon-based computers cannot do. Although brain-like chemical computers are still far beyond reach, it is of interest to explore how atom and molecule-based systems that can write, read, and store information might be designed and constructed. In this lecture I will discuss our efforts to develop a new technology to write, store, and read information, i.e. on a single polymer chain with the help of “molecular machines” that are inspired by the hypothetical device (Turing machine) proposed by the British mathematician Alan Turing in 1936 as the general basis for the operation of a computer. We are following two approaches. In the first one we try to construct molecular machines based on clamp-shaped proteins, modified with porphyrin catalysts, that can bind to DNA and move along it while modifying the DNA chain in a controlled fashion. In the second approach we use synthetic machines that are derived from chiral porphyrin cages, which bind to synthetic polymers (e.g. polybutadiene) and glide along it while encoding it with chiral epoxide functions, i.e. (R,R)-epoxide (symbol 0) and (S,S)-epoxide (symbol 1). This encoding process, which is in progress, will be controlled by light.

Mononuclear ferrous and ferric complexes

This contribution reports on the recent developments concerning spin-crossover Fe(II) and Fe(III) complexes of mononuclear nature. In the first section, the description of chemical environments encountered in this iron coordination chemistry is briefly introduced. The background related to the switchability and cooperativity of the molecular materials is followed by a summary of the very first developments directed toward applications. Presently, these molecule-based systems are broadly used for the design, the elaboration of multifunctional materials, or for more fundamental investigations of scaling effects. It will be presented with a focus on usual and unusual iron coordinances, the design of systems with multiple functionalities, and also the few coordinatively unsaturated examples that react to chemical stimuli with a spin change of the iron ion.

Synthesis, structure and magnetic properties of dinuclear cobalt-tetraoxolene complexes with bidentate terminal ligands

The design of molecule-based systems with tuneable optical and/or magnetic properties has attracted considerable attention because of their potential applications in high-performance molecule-based electronic devices, switches, sensors and displays. In this regard, a large number of valence tautomeric tetraoxolene-bridged dinuclear cobalt complexes with tetradentate ancillary ligands have been reported, but none of these complexes contained a bidentate terminal ligand. In order to increase the scope in this field, the present report describes the synthesis, structures, electrochemical and magnetic studies of two dinuclear cobalt-tetraoxolene complexes, [Co2(dhbq)(bpy)4](PF6)3 (1(PF6)3) and [Co2(dhbq)(bpa)4](PF6)3·6H2O (2(PF6)3·6H2O), where H2dhbq is 2,5-dihydroxy-1,4-benzoquinone, with the bidentate terminal ligands 2,2′-bipyridine (bpy) and 2,2′-bipyridyl amine (bpa), respectively. An X-ray diffraction study reveals that the dianionic form of the redox active tetraoxolene ligand bridges the metal centers in these complexes, and one metal center is in the high spin cobalt(II) state while the other one is in the low spin cobalt(III) state. The present report will increase knowledge on the synthesis of such systems using bidentate terminal ligands. Variable temperature magnetic susceptibility measurements show no indication for valence tautomerism (VT) in either complex. Further attempts could be made to synthesize similar complexes from different solvents and/or using different counter ions to check whether such variations can bring VT in these systems.

Free-radical sensing by using naphthalimide based mesoporous silica (MCM-41) nanoparticles: A combined fluorescence and cellular imaging study

Keeping in mind the advantages of material-based systems over simple molecule-based systems, we have designed and developed three inorganic-organic hybrid systems by anchoring 1,8-naphthalimide derivatives to mesoporous silica nanoparticles for detection of free radicals. Prior to photophysical study, systems are characterized by spectroscopic, microscopic and thermo-gravimetric techniques. Steady state and time-resolved fluorescence studies demonstrate that the hydrazine based system is senstive towards detection of various free radicals. Cellular imaging study reveals cell permeability and toxicity study demonstrates the non-toxic nature of the material. These studies have suggested that present system has the potential to be used in various biological applications.

Fine Tuning the Energy Barrier of Molecular Nanomagnets via Lattice Solvent Molecules

Solvents play important roles in our lives, they are also of interest in molecular materials, especially for molecular magnets. The solvatomagnetic effect is generally used for trigger and/or regulation of magnetic properties in molecule-based systems, however, molecular nanomagnets showing solvatomagnetic effects are very difficult to obtain. Here we report four 3d-4f heterometallic cluster complexes containing ROH lattice solvent molecules, [Cu3Tb2(H3L)2(OAc)2(hfac)4]∙2ROH {H6L = 1,3-Bis[tris(hydroxymethyl)methylamino]propane, hfac− = hexafluoroacetylacetonate; R = CH3, 1; R = C2H5, 2; R = C3H7, 3; R = H, 4}. Single-molecule magnet (SMM) properties of these four complexes were observed to be dependent on the ROH lattice solvent molecule. There is an interesting magneto-structural correlation: the larger the R group, the higher the energy barrier. For the first time, the solvatomagnetic effect is used for the continuous fine adjustment of the energy barrier of 0D molecular nanomagnets. Additionally, [Cu3Dy2(H3L)2(OAc)2(hfac)4]∙2MeOH (5), an analogue of [Cu3Tb2(H3L)2(OAc)2(hfac)4]∙2MeOH (1), is also reported for comparison.

Synthesis, crystal structure and electronic property of a tetraoxolene bridged dinuclear cobalt(II) complex with bipyridyl blocking ligand

The design of molecule-based systems displaying tuneable optical and/or magnetic properties under external perturbations has received a considerable interest because of their potential applications in high-performance molecule-based electronic devices, switches, sensors, and displays. Several valence tautomeric tetraoxolene bridged dinuclear cobalt complexes with tetradentate terminal ligands have been synthesized in this regard, but none was reported with bidentate terminal ligand. In order to increase the scope in this field, a new tetraoxolene bridged dinuclear cobalt(II) complex with three different lattice solvate molecules [Co2(bpy)4(DHBQ2−)](BPh4)2·2CH3COCH3 (1(BPh4)2·2CH3COCH3), [Co2(bpy)4(DHBQ2−)]·(BPh4)2·2MeCN (1(BPh4)2·2CH3CN) and [Co2(bpy)4(DHBQ2−)]·(BPh4)2·2DMF (1(BPh4)2·2DMF), where bpy is 2,2-bipyridine and DHBQ2− is deprotonated 2,5-dihydroxy-1,4-benzoquinone, have been reported. Their crystal structures were determined by single-crystal X-ray diffraction study. In the complex cation [Co2(bpy)4(DHBQ2−)]2+, cobalt(II) centers are hexa-coordinated by four nitrogen atoms from two bipyridine ligands and two oxygen atoms from dinegative tetraoxolene ligand which bridges two cobalt(II) ions in a bis-bidentate fashion. An extensive effort has been made to visualize the noncovalent interactions in the solid state. Electrochemical studies were also carried out to realize the electronic flexibility in these systems.

Single-molecule quantum dot as a Kondo simulator

Structural flexibility of molecule-based systems is key to realizing the novel functionalities. Tuning the structure in the atomic scale enables us to manipulate the quantum state in the molecule-based system. Here we present the reversible Hamiltonian manipulation in a single-molecule quantum dot consisting of an iron phthalocyanine molecule attached to an Au electrode and a scanning tunnelling microscope tip. We precisely controlled the position of Fe2+ ion in the molecular cage by using the tip, and tuned the Kondo coupling between the molecular spins and the Au electrode. Then, we realized the crossover between the strong-coupling Kondo regime and the weak-coupling regime governed by spin–orbit interaction in the molecule. The results open an avenue to simulate low-energy quantum many-body physics and quantum phase transition through the molecular flexibility.

Spin Dynamics and Low Energy Vibrations: Insights from Vanadyl-Based Potential Molecular Qubits.

Here we report the investigation of the magnetization dynamics of a vanadyl complex with diethyldithiocarbamate (Et2dtc-) ligands, namely [VO(Et2dtc)2] (1), in both solid-state and frozen solution. This showed an anomalous and unprecedentedly observed field dependence of the relaxation time, which was modeled with three contributions to the relaxation mechanism. The temperature dependence of the weight of the two processes dominating at low fields was found to well correlate with the low energy vibrations as determined by THz spectroscopy. This detailed experimental comparative study represents a fundamental step to understand the spin dynamics of potential molecular quantum bits, and enriches the guidelines to design molecule-based systems with enhanced quantum coherence.

Probing properties of molecule-based interface systems: general discussion and Discussion of the Concluding Remarks.

Probing properties of molecule-based interface systems: general discussion and Discussion of the Concluding Remarks.

Abstract 4196: Real-time single-walled nanotube (SWNT)-based imaging system improves tumor detection and survival in ovarian cancer animal model

Abstract Residual tumor detection in advanced stage ovarian cancer (OC) represents a critical challenge in the treatment of this disease. Optimal abdominal cytoreduction to reduce tumor to no evidence of macroscopic disease is the main endpoint of tumor debulking surgery, with demonstrated survival advantages, but the current clinically available imaging modalities have shown low tumor detection sensitivity of tumors smaller than 10 mm diameter. Instead, targeted molecule-based imaging systems offer higher detection rate and are likely to extend the aim of complete resection to the microscopic scale. We applied a custom designed imaging system to a preclinical ovarian cancer tumor model and observed higher microscopic tumor detection accuracy and survival advantage compared to non-image guided debulking surgery. A two component imaging system was developed. The contrast agent is an intra-peritoneal injectable nanomolecular probe, composed of a single walled carbon nanotube (SWNT) coupled with an engineered M13-bacteriophage carrying a modified peptide targeting secreted protein, acidic and rich in cysteine (SPARC), extracellular protein overexpressed in OC. The imaging device system is capable of detecting SWNT inherent fluorescence in near-infrared second window (NIR2) and of displaying real-time images to guide the intraoperative tumor debulking. In an orthotopic ovarian cancer animal model, the imaging system detected microscopic tumors in the millimeter and sub-millimeter scale resolution with a mean tumor diameter of 2.1 vs 3.6 mm (p< 0.01) compared to eye detected tumors. The imaging system demonstrated sensitivity of 97.2% and specificity of 69.7%, and a Receiver Operator Area under the Curve of 0.85 + 0.05. In a survival surgery animal model, the imaging guided resection surgery compared to non guided surgery showed a survival advantage for the experimental arm, with median survival time of 41.0 days vs 28.5 days, respectively (HR 0.22, 95% CI of ratio 0.04 to 1.08 Log Rank test: p: 0.063). The accuracy of the imaging system and its survival advantage are promising. The survival outcome improvement in this preclinical model supports the translation to first-in-human investigation. Moreover, the imaging system accuracy suggests further exploitation in targeted delivery therapies. Citation Format: Lorenzo Ceppi, YoungJeong Na, Neelkanth M. Bardhan, Andrew Siegel, Nandini Rajan, Angela M. Belcher, Michael J. Birrer. Real-time single-walled nanotube (SWNT)-based imaging system improves tumor detection and survival in ovarian cancer animal model. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4196.

Harnessing Reversible Electronic Energy Transfer: From Molecular Dyads to Molecular Machines.

Reversible electronic energy transfer (REET) may be instilled in bi-/multichromophoric molecule-based systems, following photoexcitation, upon judicious structural integration of matched chromophores. This leads to a new set of photophysical properties for the ensemble, which can be fully characterized by steady-state and time-resolved spectroscopic methods. Herein, we take a comprehensive look at progress in the development of this type of supermolecule in the last five years, which has seen systems evolve from covalently tethered dyads to synthetic molecular machines, exemplified by two different pseudorotaxanes. Indeed, REET holds promise in the control of movement in molecular machines, their assembly/disassembly, as well as in charge separation.

Gold, Silver and Carbon Nanoparticles Grafted on Activated Polymers for Biomedical Applications

Organic polymers have been applied successfully in fields such as adhesion, biomaterials, protective coatings, friction and wear, composites, microelectronic devices, and thin-film technology. In general, special surface properties with regard to chemical composition, hydrophilicity, roughness, crystallinity, conductivity, lubricity, and cross-linking density are required for the success of these applications. Polymers very often do not possess the surface properties needed for these applications. For these reasons, surface modification techniques which can transform these inexpensive materials into highly valuable finished products have become an important part of the plastics industry. In case of biomedical polymers is plasma treatment used for enhancing cell adhesion, growth and proliferation and to make them suitable for implants and tissue engineering scaffolds. Nanoparticles fascinated scientists for over a century and are now heavily utilized in chemistry, biology, engineering, and medicine. Nowadays nanoparticles can be synthesized reproducibly, modified with seemingly limitless chemical functional groups, and, in certain cases, characterized with atomic-level precision. In recent years, focus has turned to therapeutic possibilities for such materials. Structures, which behave as drug carriers, antimicrobial agents, and photoresponsive therapeutics have been developed and studied in the context of cells and many debilitating diseases. These structures are not simply chosen as alternatives to molecule-based systems, but rather for their new physical and chemical properties, which confer substantive advantages in cellular and medical applications. In this review, we provide insights into immobilization, toxicity and biomedical applications of gold, silver and carbon nanoparticles and discuss their grafting to polymer substrates and the influence on cell-material interactions. The adhesion and the response of cells in contact with the surface play an important role in the cytocompatibility of the implant. It is thus important to understand how cells interact with their environment. The main properties decisive for colonization of a material with cells are surface chemistry, roughness, morphology and polarity, wettability and electrical charge.