Antibacterial surfaces have an enormous economic and social impact on the worldwide technological fight against diseases. However, bacteria develop resistance and coatings are often not uniform and not stable in time. The challenge is finding an antibacterial coating that is biocompatible, cost-effective, not toxic, and spreadable over large and irregular surfaces. Here we demonstrate an antibacterial cloak by laser printing of graphene oxide hydrogels mimicking the Cancer Pagurus carapace. We observe up to 90% reduction of bacteria cells. This cloak exploits natural surface patterns evolved to resist to microorganisms infection, and the antimicrobial efficacy of graphene oxide. Cell integrity analysis by scanning electron microscopy and nucleic acids release show bacteriostatic and bactericidal effect. Nucleic acids release demonstrates microorganism cutting, and microscopy reveals cells wrapped by the laser treated gel. A theoretical active matter model confirms our findings. The employment of biomimetic graphene oxide gels opens unique possibilities to decrease infections in biomedical applications and chirurgical equipment; our antibiotic-free approach, based on the geometric reduction of microbial adhesion and the mechanical action of Graphene Oxide sheets, is potentially not affected by bacterial resistance.

Solid state quantum emitters are a mainstay of quantum nanophotonics as integrated single photon sources (SPS) and optical nanoprobes. Integrating such emitters with active nanophotonic elements is desirable in order to attain efficient control of their optical properties but typically degrades the photostability of the emitter itself. Here, we demonstrate a tuneable hybrid device that integrates lifetime-limited single emitters (linewidth ~ 40 MHz) and 2D materials at sub-wavelength separation without degradation of the emission properties. Our device's nanoscale dimensions enable ultra-broadband tuning (tuning range > 400 GHz) and fast modulation (frequency ~ 100 MHz) of the emission energy, which renders it an integrated, ultra-compact tuneable SPS. Conversely, this offers a novel approach to optical sensing of 2D material properties using a single emitter as a nanoprobe.Hybrid nanophotonic systems blend the strengths of distinct photonic elements to strongly enhance light-matter interactions 1 in integrated photonic circuits. In these systems, narrow-linewidth quantum light emitters play a key role as single photon sources (SPS) which interact with their nanoscale environment 2,3 . Controlling these interactions provides versatile SPS tuning 4 required for coupling quantum resources [5][6][7] . Integrating nanoscale light emitters with two-dimensional (2D) materials is motivated by the rich physics of near-field interactions 8 and new hybrid light-matter states 9,10 . This approach unites integrated solid-state SPS such as nitrogen vacancy centres 11 , quantum dots 12 and single molecules 13 with the diverse optoelectronic properties of 2D materials that facilitate emitting 14 , controlling [15][16][17] and detecting 18 light at the nanoscale. In such hybrid devices, quantum emitters can be integrated at sub-wavelength separation to the 2D interface to achieve efficient near-field coupling 8 , which modifies the emitter's radiative decay rate [19][20][21] or transition energy 22,23 . Recent experimental studies integrated 2D materials with ensembles of broadband emitters to demonstrate electrical 24-26 and electromechanical 27 tuning of the decay rate by controlling non-radiative energy transfer (nRET) or the energy flow to confined electromagnetic modes such as 2D polaritons 26,28 . Therefore, hybrids of 2D materials and SPS have the potential for in situ control of the conversion and channelling of single photons at the nanoscale. So far, these studies have been limited to ensembles and broad linewidth emitters. Integrating bright and narrow quantum emitters in such systems paves 2 the way towards a tuneable quantum light-matter interface, which is an essential ingredient for integrated quantum networks.Here, we demonstrate hybrid integration of 2D materials (semi-metallic graphene or semi-conducting MoS2) with single, lifetime-limited quantum emitters in nanocrystals to provide active emission control. Using the 2D materials as transparent electrodes, we show broadband Stark tuning of the emission energy o...

Graphene and graphene oxide (GO) are capable of inducing stem cells differentiation into bone tissue with variable efficacy depending on reductive state of the material. Thus, modulation of osteogenic process and of bone mineral density distribution is theoretically possible by controlling the GO oxidative state. In this study, we laser-printed GO surfaces in order to obtain both a local photo-thermal GO reduction and the formation of nano-wrinkles along precise geometric pattern. Initially, after cells adhered on the surface, stem cells migrated and accumulated on the reduced and wrinkled surface. When the local density of the stem cells on the reduced stripes was high, cells started to proliferate and occupy the oxidized/flat area. The designed surfaces morphology guided stem cell orientation and the reduction accelerated differentiation. Furthermore the reduced sharp nano-wrinkles were able to enhance the GO antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), a common cause of prosthetic joints infections. This strategy can offer a revolution in present and future trends of scaffolds design for regenerative medicine.