The field of medical micro/nanorobotics holds considerable promise for advancing medical diagnosis and treatment due to their unique ability to move and perform complex task at small scales. Nevertheless, the grand challenge of the field remains in its successful translation towards widespread patient use. We critically address the frontiers of the current methodologies for in vivo applications and discuss the current and foreseeable perspectives of their commercialization. Although no “killer application” that would catalyze rapid commercialization has yet emerged, recent engineering breakthroughs have led to the successful in vivo operation of medical micro/nanorobots. We also highlight how standardizing report summaries of micro/nanorobotics is essential not only for increasing the quality of research but also for minimizing investment risk in their potential commercialization. We review current patents and commercialization efforts based on emerging proof-of-concept applications. We expect to inspire future research efforts in the field of micro/nanorobotics toward future medical diagnosis and treatment.

A microneedle electrochemical biosensor for the minimally invasive detection of organophosphate (OP) chemical agents is described. The new sensor relies on the coupling of the effective biocatalytic action of organophosphorus hydrolase (OPH) with a hollow-microneedle modified carbon-paste array electrode transducer, and involves rapid square-wave voltammetric (SWV) measurements of the p-nitrophenol product of the OPH enzymatic reaction in the presence of the OP substrate. The scanning-potential SWV transduction mode offers an additional dimension of selectivity compared to common fixed-potential OPH-amperometric biosensors. The microneedle device offers a highly linear response for methyl paraoxon (MPOx) over the range of 20-180 μM, high selectivity in the presence of excess co-existing ascorbic acid and uric acid and a high stability sensor upon exposure to the interstitial fluid (ISF). The OPH microneedle sensor was successfully tested ex vivo using mice skin samples exposed to MPOx, demonstrating its promise for minimally-invasive monitoring of OP agents and pesticides and as a wearable sensor for detecting toxic compounds, in general.

Molybdenum trioxide (MoO3), an important transition metal oxide (TMO), has been extensively investigated over the past few decades due to its potential in existing and emerging technologies, including catalysis, energy and data storage, electrochromic devices, and sensors. Recently, the growing interest in two-dimensional (2D) materials, often rich in interesting properties and functionalities compared to their bulk counterparts, has led to the investigation of 2D MoO3. However, the realization of large-area true 2D (single to few atom layers thick) MoO3 is yet to be achieved. Here, we demonstrate a facile route to obtain wafer-scale monolayer amorphous MoO3 using 2D MoS2 as a starting material, followed by UV–ozone oxidation at a substrate temperature as low as 120 °C. This simple yet effective process yields smooth, continuous, uniform, and stable monolayer oxide with wafer-scale homogeneity, as confirmed by several characterization techniques, including atomic force microscopy, numerous spectroscopy methods, and scanning transmission electron microscopy. Furthermore, using the subnanometer MoO3 as the active layer sandwiched between two metal electrodes, we demonstrate the thinnest oxide-based nonvolatile resistive switching memory with a low voltage operation and a high ON/OFF ratio. These results (potentially extendable to other TMOs) will enable further exploration of subnanometer stoichiometric MoO3, extending the frontiers of ultrathin flexible oxide materials and devices.

patch technology has led to significant surge in first-generation transdermal patches. [19][20][21][22] The marriage between effective needle-free delivery platforms and wearable devices could thus prove highly desirable. However, achieving the desired therapeutic or detoxification effect requires further attention to the low permeability of the human skin.Herein, we present a flexible epidermal tattoo patch, containing thousands of microcannons, for efficient ultrasoundtriggered microballistic transdermal cargo delivery. The new conformal patch consists of a commercial temporary transfer tattoo paper combined with a microporous membrane whose micropores are fully loaded with the desired payload mixed with a perfluorocarbon emulsion (Figure 1). Application of a high intensity focused ultrasound pulse vaporizes the perfluorocarbon emulsion, resulting in the rapid ejection of the payload. This microballistic capability is exploited in the present work to create skin-worn flexible tattoo capable of the high thrust toward penetrating soft adherent surfaces. We demonstrate the ability of this flexible porousmembrane tattoo microballistic delivery patch to conform to the nonplanar irregular surface of the skin and withstand a variety of repeated mechanical strains experienced during day-to-day activities. Furthermore, we characterize this tattoo patch's cargo loading and scalability through volume calculations and its drug delivery effectiveness through penetration depth tests. Finally, using skin-mimicking phantoms, because of its transparent nature compared to opaque skin, we demonstrate the practical utility and enhanced permeation capability of the new epidermal tattoo patch for delivering cerium-oxide (CeO 2 ) microparticles for improved decontamination of an organophosphorus nerve agent in a phantom skin model and toward the enhanced delivery of the chemotherapeutic drug doxorubicin (in comparison to passive diffusion). These results demonstrate that this flexible and conformal tattoo-based patch acoustic microballistic delivery platform could pave the way for new efficient noninvasive treatments toward overcoming permeability barriers in connection to diverse biomedical and biodefense applications.

While phosphonium phosphate ionic liquids (ILs) have been evaluated as additives for engine oils owing to their excellent physico‐chemical properties, miscibility with hydrocarbon fluids, and promising tribological properties, their lubrication mechanism is still not established. Here, atomic force microscopy (AFM) nanotribological experiments are performed using diamond‐like carbon‐coated silicon tips sliding on air‐oxidized steel in neat trihexyltetradecylphosphonium bis(2‐ethylhexyl)phosphate IL. The AFM results indicate a reduction in friction only after the removal of the native oxide layer from steel. Laterally resolved analyses of the steel surface chemistry reveal a higher concentration of bis(2‐ethylhexyl)phosphate ions adsorbed on regions where the native oxide is mechanically removed together with a change in surface electrostatic potential. These surface modifications are proposed to be induced by a change in adsorption configuration of bis(2‐ethylhexyl)phosphate anions on metallic iron compared to their configuration on iron oxide together with a reduction of surface roughness, which lead to the formation of a densely packed, lubricious boundary layer only on metallic iron.

Pure molybdenum disulfide (MoS2) solid lubricant coatings could attain densities comparable to doped films (and the associated benefits to wear rate and environmental stability) through manipulation of the microstructure via deposition parameters. Unfortunately, pure films can exhibit highly variable microstructures and mechanical properties due to processes that are not controlled during deposition (i.e., batch-to-batch variation). This work focuses on developing a relationship between density, hardness, friction, and wear for pure sputtered MoS2 coatings. Results show that dense films (ρ = 4.5 g/cm3) exhibit a 100 × lower wear rate compared to porous coatings (ρ = 3.04–3.55 g/cm3). The tribological performance of high density pure MoS2 coatings is shown to surpass that of established composite coatings, achieving a wear rate 2 × (k = 5.74 × 10–8 mm3/Nm) lower than composite MoS2/Sb2O3/Au in inert environments.

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In this work, we perform atomic force microscopy (AFM) experiments to evaluate in situ the dependence of the structural morphology of trihexyltetradecylphosphonium bis(2-ethylhexyl) phosphate ([P6,6,6,14][DEHP]) ionic liquid (IL) on applied pressure.