Advanced extracellular vesicle bioinformatic nanomaterials: from enrichment, decoding to clinical diagnostics.

Extracellular vesicles (EVs) are membrane nanoarchitectures generated by cells that carry a variety of biomolecules, including DNA, RNA, proteins and metabolites. These characteristics make them attractive as circulating bioinformatic nanocabinets for liquid biopsy. Recent advances on EV biology and biogenesis demonstrate that EVs serve as highly important cellular surrogates involved in a wide range of diseases, opening up new frontiers for modern diagnostics. However, inefficient methods for EV enrichment, as well as low sensitivity of EV bioinformatic decoding technologies, hinder the use of EV nanocabinet for clinical diagnosis. To overcome these challenges, new EV nanotechnology is being actively developed to promote the clinical translation of EV diagnostics. This article aims to present the emerging enrichment strategies and bioinformatic decoding platforms for EV analysis, and their applications as bioinformatic nanomaterials in clinical settings.

Biomimetic 3D Recognition with 2D Flexible Nanoarchitectures for Ultrasensitive and Visual Extracellular Vesicle Detection.

Despite increasing recognition of extracellular vesicles being important circulating biomarkers in disease diagnosis and prognosis, current strategies for extracellular vesicle detection remain limited due to the compromised sample purification and extensive labeling procedures in complex body fluids. Here, we developed a 2D magnetic platform that greatly improves capture efficiency and readily realizes visible signal conversion for extracellular vesicle detection. The technology, termed high-affinity recognition and visual extracellular vesicle testing (HARVEST), leverages 2D flexible Fe3O4-MoS2 nanostructures to recognize extracellular vesicles through multidentate affinity binding and feasible magnetic separation, thus enhancing the extracellular vesicle capture performance with both yield and separation time, affording high sensitivity with the detection limit of 20 extracellular vesicle particles/µL. Through integration with lipid labeling chemistry and the fluorescence visualization system, the platform enables rapid and visible detection. The number of extracellular vesicles can be feasibly determined by smart mobile phones, readily adapted for point-of-care diagnosis. When clinically evaluated, the strategy accurately differentiates melanoma samples from the normal cohort with an AUC of 0.98, demonstrating the efficient extracellular vesicle detection strategy with 2D flexible platforms for cancer diagnosis.

915 nm Light-Triggered Photodynamic Therapy and MR/CT Dual-Modal Imaging of Tumor Based on the Nonstoichiometric Na0.52 YbF3.52 :Er Upconversion Nanoprobes.

Lanthanide (Ln(3+) )-doped upconversion nanoparticles (UCNPs) as a new generation of multimodal bioprobes have attracted great interest for theranostic purpose. Herein, red emitting nonstoichiometric Na0.52 YbF3.52 :Er UCNPs of high luminescence intensity and color purity are synthesized via a facile solvothermal method. The red UC emission from the present nanophosphors is three times more intense than the well-known green emission from the ≈30 nm sized hexagonal-phase NaYF4 :Yb,Er UCNPs. By utilizing Na0.52 YbF3.52 :Er@SrF2 UCNPs as multifunctional nanoplatforms, highly efficient in vitro and in vivo 915 nm light-triggered photodynamic therapies are realized for the first time, with dramatically diminished overheating yet similar therapeutic effects in comparison to those triggered by 980 nm light. Moreover, by virtue of the high transverse relaxivity (r 2 ) and the strong X-ray attenuation ability of Yb(3+) ions, these UCNPs also demonstrate good performances as contrast agents for high contrast magnetic resonance and X-ray computed tomography dual-modal imaging. Our research shows the great potential of the red emitting Na0.52 YbF3.52 :Er UCNPs for multimodal imaging-guided photodynamic therapy of tumors.

Surface plasmon resonance enhanced light absorption and photothermal therapy in the second near-infrared window.

Enhanced near-field at noble metal nanoparticle surfaces due to localized surface plasmon resonance (LSPR) has been researched in fields ranging from biomedical to photoelectrical applications. However, it is rarely explored on nonmetallic nanomaterials discovered in recent years, which can also support LSPR by doping-induced free charge carriers, let alone the investigation of an intricate system involving both. Here we construct a dual plasmonic hybrid nanosystem Au-Cu9S5 with well controlled interfaces to study the coupling effect of LSPR originating from the collective electron and hole oscillations. Cu9S5 LSPR is enhanced by 50% in the presence of Au, and the simulation results confirm the coupling effect and the enhanced local field as well as the optical power absorption on Cu9S5 surface. This enhanced optical absorption cross section, high photothermal transduction efficiency (37%), large light penetration depth at 1064 nm, excellent X-ray attenuation ability, and low cytotoxicity enable Au-Cu9S5 hybrids for robust photothermal therapy in the second near-infrared (NIR) window with low nanomaterial dose and laser flux, making them potential theranostic nanomaterials with X-ray CT imaging capability. This study will benefit future design and optimization of photoabsorbers and photothermal nanoheaters utilizing surface plasmon resonance enhancement phenomena for a broad range of applications.

Programmed Nanocloak of Commensal Bacteria-Derived Nanovesicles Amplify Strong Immunoreactivity against Tumor Growth and Metastatic Progression.

Recent discoveries in commensal microbiota demonstrate the great promise of intratumoral bacteria as attractive molecular targets of tumors in improving cancer treatment. However, direct leveraging of in vivo antibacterial strategies such as antibiotics to potentiate cancer therapy often leads to uncertain effectiveness, mainly due to poor selectivity and potential adverse effects. Here, building from the clinical discovery that patients with breast cancer featured rich commensal bacteria, we developed an activatable biointerface by encapsulating commensal bacteria-derived extracellular vesicles (BEV) with a responsive nanocloak to potentiate immunoreactivity against intratumoral bacteria and breast cancer. We show that the interfacially cloaked BEV (cBEV) not only overcame serious systemic side responses but also demonstrated heightened immunogenicity by intercellular responsive immunogenicity, facilitating dendritic cell maturation through activating the cGAS-STING pathway. As a preventive measure, vaccination with nanocloaked cBEVs achieved strong protection against bacterial infection, largely providing prophylactic efficiency against tumor challenges. When treated in conjunction with immune checkpoint inhibitor anti-PD-L1 antibodies, the combined approach elicited a potent tumor-specific immune response, synergistically inhibiting tumor progression and mitigating lung metastases.

White light powered antimicrobial nanoagents for triple photothermal, chemodynamic and photodynamic based sterilization.

Antibacterial nanoagents have been increasingly developed due to their favorable biocompatibility, cost-effective raw materials, and alternative chemical or optical properties. Nevertheless, there is still a pressing need for antibacterial nanoagents that exhibit outstanding bacteria-binding capabilities and high antibacterial efficiency. In this study, we constructed a multifunctional cascade bioreactor (GCDCO) as a novel antibacterial agent. This involved incorporating carbon dots (CDs), cobalt sulfide quantum dots (CoSx QDs), and glucose oxidase (GOx) to enhance bacterial inhibition under sunlight irradiation. The GCDCO demonstrated highly efficient antibacterial capabilities attributed to its favorable photothermal properties, photodynamic activity, as well as the synergistic effects of hyperthermia, glucose-augmented chemodynamic action, and additional photodynamic activity. Within this cascade bioreactor, CDs played the role of a photosensitizer for photodynamic therapy (PDT), capable of generating ˙O2- even under solar light irradiation. The CoSx QDs not only functioned as a catalytic component to decompose hydrogen peroxide (H2O2) and generate hydroxyl radicals (˙OH), but they also served as heat generators to enhance the Fenton-like catalysis process. Furthermore, GOx was incorporated into this cascade bioreactor to internally supply H2O2 by consuming glucose for a Fenton-like reaction. As a result, GCDCO could generate a substantial amount of reactive oxygen species (ROS), leading to a significant synergistic effect that greatly induced bacterial death. Furthermore, the in vitro antibacterial experiment revealed that GCDCO displayed notably enhanced antibacterial activity against E. coli (99+ %) when combined with glucose under simulated sunlight, surpassing the efficacy of the individual components. This underscores its remarkable efficiency in combating bacterial growth. Taken together, our GCDCO demonstrates significant potential for use in the routine treatment of skin infections among diabetic patients.

Mechanoelectronic stimulation of autologous extracellular vesicle biosynthesis implant for gut microbiota modulation.

Pathogenic gut microbiota is responsible for a few debilitating gastrointestinal diseases. While the host immune cells do produce extracellular vesicles to counteract some deleterious effects of the microbiota, the extracellular vesicles are of insufficient doses and at unreliable exposure times. Here we use mechanical stimulation of hydrogel-embedded macrophage in a bioelectronic controller that on demand boost production of up to 20 times of therapeutic extracellular vesicles to ameliorate the microbes' deleterious effects in vivo. Our miniaturized wireless bioelectronic system termed inducible mechanical activation for in-situ and sustainable generating extracellular vesicles (iMASSAGE), leverages on wireless electronics and responsive hydrogel to impose mechanical forces on macrophages to produce extracellular vesicles that rectify gut microbiome dysbiosis and ameliorate colitis. This in vivo controllable extracellular vesicles-produced system holds promise as platform to treat various other diseases.

Size-Controllable Nanosystem with Double Responsive for Deep Photodynamic Therapy.

Photodynamic therapy (PDT) is a promising strategy for cancer treatment. However, a poor tissue penetration of activation light and low target specificity seriously hindered the clinical application of PDT. Here, we designed and constructed a size-controllable nanosystem (UPH) with inside-out responsive for deep PDT with enhanced biosafety. To obtain nanoparticles with the best quantum yield, a series of core-shell nanoparticles (UCNP@nPCN) with different thicknesses were synthesized by a layer-by-layer self-assembly method to incorporate a porphyritic porous coordination network (PCN) onto the surface of upconverting nanoparticles (UCNPs), followed by coating with hyaluronic acid (HA) on the surface of nanoparticles with optimized thickness to form the UPH nanoparticles. With the aid of HA, the UPH nanoparticles were capable of preferentially enriching in tumor sites and specific endocytosis by CD44 receptors as well as responsive degradation by hyaluronidase in cancer cells after intravenous administration. Subsequently, after being activated by strong penetrating 980 nm near-infrared light (NIR), the UPH nanoparticles efficiently converted oxygen into strongly oxidizing reactive oxygen species based on the fluorescence resonance energy transfer (FRET) effect, thereby significantly inhibiting tumor growth. Experimental results in vitro and in vivo indicated that such dual-responsive nanoparticles successfully realize the photodynamic therapy of deep-seated cancer with negligible side effects, which showed great potential for potential clinical translational research.

Advances in Extracellular Vesicle Nanotechnology for Precision Theranostics.

Extracellular vesicles (EVs) have increasingly been recognized as important cell surrogates influencing many pathophysiological processes, including cellular homeostasis, cancer progression, neurologic disease, and infectious disease. These behaviors enable EVs broad application prospects for clinical application in disease diagnosis and treatment. Many studies suggest that EVs are superior to conventional synthetic carriers in terms of drug delivery and circulating biomarkers for early disease diagnosis, opening up new frontiers for modern theranostics. Despite these clinical potential, EVs containing diverse cellular components, such as nucleic acids, proteins, and metabolites are highly heterogeneous and small size. The limitation of preparatory, engineering and analytical technologies for EVs poses technical barriers to clinical translation. This article aims at present a critical overview of emerging technologies in EVs field for biomedical applications and challenges involved in their clinic translations. The current methods for isolation and identification of EVs are discussed. Additionally, engineering strategies developed to enhance scalable production and improved cargo loading as well as tumor targeting are presented. The superior clinical potential of EVs, particularly in terms of different cell origins and their application in the next generation of diagnostic and treatment platforms, are clarified.

Paintable Bioactive Extracellular Vesicle Ink for Wound Healing.

The treatment of cutaneous wounds involving complex biological processes has become a significant public health concern worldwide. Here, we developed an efficient extracellular vesicle (EV) ink to regulate the inflammatory microenvironment and promote vascular regeneration for wound healing. The technology, termed portable bioactive ink for tissue healing (PAINT), leverages bioactive M2 macrophage-derived EVs (EVM2) and a sodium alginate precursor, forming a biocompatible EV-Gel within 3 min after mixing, enabling it to be smeared on wounds in situ to meet diverse morphologies. The bioactive EVM2 reprogram macrophage polarization and promote the proliferation and migration of endothelial cells, thereby effectively regulating inflammation and enhancing angiogenesis in wounds. Through integration with a 3D printing pen, the platform enables EV-Gel to be applied to wound sites having arbitrary shapes and sizes with geometric matches for tissue repairment. When evaluated using a mouse wound model, PAINT technology accelerates cutaneous wound healing by promoting the angiogenesis of endothelial cells and the polarization of macrophages to M2 phenotype in vivo, demonstrating the high potential of bioactive EV ink as a portable biomedical platform for healthcare.

Cyclodextrin-Based Nanoplatforms for Tumor Phototherapy: An Update.

Tumor phototherapies are light-mediated tumor treatment modalities, which usually refer to tumor photothermal therapy (PTT) and photodynamic therapy (PDT). Due to the outstanding spatial-temporal control over treatment through light irradiation, tumor phototherapies display extremely low side effects during treatment and are believed to be a tumor treatment method with a clinical translation potential. However, current tumor phototherapy nanoplatforms face obstacles, including light irradiation-induced skin burning, tumor hypoxia microenvironments, limited light penetration depth, et al. Therefore, one important research direction is developing a tumor phototherapy nanoplatform with multifunctionality and enhanced pharmacological effects to overcome the complexity of tumor treatment. On the other hand, cyclodextrins (CDs) are starch-originated circular oligosaccharides with negligible toxicity and have been used to form supermolecular nanostructures through a host-guest interaction between the inner cavity of CDs and functional biomolecules. In the past few years, numerous studies have focused on CD-based multifunctional tumor phototherapy nanoplatforms with an enhanced photoeffect, responsive morphological transformation, and elevated drug bioavailability. This review focuses on the preparation methods of CD-based tumor phototherapy nanoplatforms and their unique physiochemical properties for improving anti-tumor pharmacological efficacy.

Defect-Rich Molybdenum Sulfide Quantum Dots for Amplified Photoluminescence and Photonics-Driven Reactive Oxygen Species Generation.

Transition metal dichalcogenide (TMD) quantum dots (QDs) with defects have attracted interesting chemistry due to the contribution of vacancies to their unique optical, physical, catalytic, and electrical properties. Engineering defined defects into molybdenum sulfide (MoS2 ) QDs is challenging. Herein, by applying a mild biomineralization-assisted bottom-up strategy, blue photoluminescent MoS2 QDs (B-QDs) with a high density of defects are fabricated. The two-stage synthesis begins with a bottom-up synthesis of original MoS2 QDs (O-QDs) through chemical reactions of Mo and sulfide ions, followed by alkaline etching that creates high sulfur-vacancy defects to eventually form B-QDs. Alkaline etching significantly increases the photoluminescence (PL) and photo-oxidation. An increase in defect density is shown to bring about increased active sites and decreased bandgap energy; which is further validated with density functional theory calculations. There is strengthened binding affinity between QDs and O2 due to lower gap energy (∆EST ) between S1 and T1 , accompanied with improved intersystem crossing (ISC) efficiency. Lowered gap energy contributes to assist e- -h+ pair formation and the strengthened binding affinity between QDs and 3 O2 . Defect engineering unravels another dimension of material properties control and can bring fresh new applications to otherwise well characterized TMD nanomaterials.

Sub-Band Gap Absorption and Optical Nonlinear Response of MnPSe3 Nanosheets for Pulse Generation in the L-Band.

Two-dimensional (2D) materials have attracted extensive attention for use in fiber lasers for pulse generation due to their unique nonlinear optical properties. While 2D materials with tunable band gaps hold promise as versatile saturable absorber materials, their L-band (long-band) pulse generation capability remains challenging. Metal phosphorus trichalcogenides (MPX3) have recently attracted the attention of researchers and shown potential for sub-band gap saturable absorption in the L-band due to their high diversity of chemical components and band structural complexity. Herein, high-quality MnPSe3 is synthesized and exhibits broad-band linear and nonlinear absorption with the modulation depth and saturation intensity of 5.4% and 0.295 MW/cm2, respectively. Moreover, a stable passive pulse generation in the L-band is demonstrated in a fiber laser. The wavelengths of the passively pulsed laser at different pump powers are recorded, featuring a fixed central wavelength located at around 1602 nm with a maximum output power of 19.54 mW. This research promotes the realization of L-band pulsed lasers based on 2D materials, inspiring further exploration of the unique properties of the MPX3 family.

Gold-based Inorganic Nanohybrids for Nanomedicine Applications.

Noble metal Au nanoparticles have attracted extensive interests in the past decades, due to their size and morphology dependent localized surface plasmon resonances. Their unique optical property, high chemical stability, good biocompatibility, and easy functionalization make them promising candidates for a variety of biomedical applications, including bioimaging, biosensing, and cancer therapy. With the intention of enhancing their optical response in the near infrared window and endowing them with additional magnetic properties, Au nanoparticles have been integrated with other functional nanomaterials that possess complementary attributes, such as copper chalcogenides and magnetic metal oxides. The as constructed hybrid nanostructures are expected to exhibit unconventional properties compared to their separate building units, due to nanoscale interactions between materials with different physicochemical properties, thus broadening the application scope and enhancing the overall performance of the hybrid nanostructures. In this review, we summarize some recent progresses in the design and synthesis of noble metal Au-based hybrid inorganic nanostructures for nanomedicine applications, and the potential and challenges for their clinical translations.

2D magnetic MoS2-Fe3O4 hybrid nanostructures for ultrasensitive exosome detection in GMR sensor.

Exosome released from cells plays an important role in intercellular communication and show great clinical potential in early cancer screening and prognosis. Herein, an ultrasensitive Giant Magnetoresistance (GMR) biosensor was developed for exosome detection, which was based on 2D MoS2-Fe3O4 nanostructures (MOFE) as magnetic responsive probes for signal amplification. The MOFE can be readily synthesized with simple phase transfer method. Compared to pure Fe3O4 magnetic nanoparticles (MNPs), the layered MoS2 function as a template for recruiting high loading density of MNPs as magnetic probes. After modified by aptamer, we discover that the 2D magnetic MOFE hybrid nanostructures enable both multidentate targeting and multi-magnetic particle-based signal amplification, increasing the magnetic sensor performance, especially in sensitivity and output signal. Moreover, the 2D magnetic nanocomposites afford high selectivity and excellent reproducibility with detection limit of 100 exosomes in GMR sensor. Results demonstrate that the magnetic strategy based on 2D structures introduced here provide a new dimension for exosome detection, which show great potential of engineering 2D magnetic nanobioprobes for GMR based liquid biopsy application.

Phototherapy with layered materials derived quantum dots.

Quantum dots (QDs) originating from two-dimensional (2D) sheets of graphitic carbon nitride (g-C3N4), graphene, hexagonal boron nitride (h-BN), monoatomic buckled crystals (phosphorene), germanene, silicene and transition metal dichalcogenides (TMDCs) are emerging zero-dimensional materials. These QDs possess diverse optical properties, are chemically stable, have surprisingly excellent biocompatibility and are relatively amenable to surface modifications. It is therefore not difficult to see that these QDs have potential in a variety of bioapplications, including biosensing, bioimaging and anticancer and antimicrobial therapy. In this review, we briefly summarize the recent progress of these exciting QD based nanoagents and strategies for phototherapy. In addition, we will discuss about the current limitations, challenges and future prospects of QDs in biomedical applications.

Increasing the Potential Interacting Area of Nanomedicine Enhances Its Homotypic Cancer Targeting Efficacy.

The cancer cell membrane contains an arsenal of highly specific homotypic moieties that can be used to recognize its own kind. These cell membranes are often used to coat spherical nanoparticles to enhance nanomedicines' targeting specificities and uptakes. A sphere, however, has only a point contact with a surface at any given time. It is shown here that, by retaining a flatter morphology of the cracked cell membrane through stiffening with in situ synthesized gold nanomaterials, an increased area of interaction could be maintained and hence improve upon the in vitro and in vivo homotypic targeting capabilities between cancer cell types. This enhancement is especially important in vivo as any nanomedicine with targeting moieties probably has a single pass at interacting with the target cell before subsequent system clearance. Possible future clinical applications may involve the usage of a patient's autologous tumor biopsy tissues, which are very limited in supply, and therefore ensuring that we capitalize on the entire collective surface area of the cancer cell membrane available becomes an important consideration in the design and delivery our cell membrane-derived nanomedicines.

Defect engineered bioactive transition metals dichalcogenides quantum dots.

Transition metal dichalcogenide (TMD) quantum dots (QDs) are fundamentally interesting because of the stronger quantum size effect with decreased lateral dimensions relative to their larger 2D nanosheet counterparts. However, the preparation of a wide range of TMD QDs is still a continual challenge. Here we demonstrate a bottom-up strategy utilizing TM oxides or chlorides and chalcogen precursors to synthesize a small library of TMD QDs (MoS2, WS2, RuS2, MoTe2, MoSe2, WSe2 and RuSe2). The reaction reaches equilibrium almost instantaneously (~10-20 s) with mild aqueous and room temperature conditions. Tunable defect engineering can be achieved within the same reactions by deviating the precursors' reaction stoichiometries from their fixed molecular stoichiometries. Using MoS2 QDs for proof-of-concept biomedical applications, we show that increasing sulfur defects enhanced oxidative stress generation, through the photodynamic effect, in cancer cells. This facile strategy will motivate future design of TMDs nanomaterials utilizing defect engineering for biomedical applications.

Nanoparticles promote in vivo breast cancer cell intravasation and extravasation by inducing endothelial leakiness.

While most cancer nanomedicine is designed to eliminate cancer, the nanomaterial per se can lead to the formation of micrometre-sized gaps in the blood vessel endothelial walls. Nanomaterials-induced endothelial leakiness (NanoEL) might favour intravasation of surviving cancer cells into the surrounding vasculature and subsequently extravasation, accelerating metastasis. Here, we show that nanoparticles induce endothelial leakiness through disruption of the VE-cadherin-VE-cadherin homophilic interactions at the adherens junction. We show that intravenously injected titanium dioxide, silica and gold nanoparticles significantly accelerate both intravasation and extravasation of breast cancer cells in animal models, increasing the extent of existing metastasis and promoting the appearance of new metastatic sites. Our results add to the understanding of the behaviour of nanoparticles in complex biological systems. The potential for NanoEL needs to be taken into consideration when designing future nanomedicines, especially nanomedicine to treat cancer.

Barcoded DNA nanostructures for the multiplexed profiling of subcellular protein distribution.

Massively parallel DNA sequencing is established, yet high-throughput protein profiling remains challenging. Here, we report a barcoding approach that leverages the combinatorial sequence content and the configurational programmability of DNA nanostructures for high-throughput multiplexed profiling of the subcellular expression and distribution of proteins in whole cells. The barcodes are formed by in situ hybridization of tetrahedral DNA nanostructures and short DNA sequences conjugated with protein-targeting antibodies, and by nanostructure-assisted ligation (either enzymatic or chemical) of the nanostructures and exogenous DNA sequences bound to nanoparticles of different sizes (which cause these localization sequences to differentially distribute across subcellular compartments). Compared with linear DNA barcoding, the nanostructured barcodes enhance the signal by more than 100-fold. By implementing the barcoding approach on a microfluidic device for the analysis of rare patient samples, we show that molecular subtypes of breast cancer can be accurately classified and that subcellular spatial markers of disease aggressiveness can be identified.