Fast and Dynamic Mapping of the Protein Corona on Nanoparticle Surfaces by Photocatalytic Proximity Labeling

Multiprobe Photoproximity Labeling of the EGFR Interactome in Glioblastoma Using Red-Light

Photocatalytic proximity labeling has emerged as a valuable technique for studying interactions between biomolecules in a cellular context, providing precise spatiotemporal control over protein labeling. One significant advantage of these methods is their modularity, allowing the use of a single photocatalyst with different reactive probes to expand interactome coverage and capture diverse protein interactions. Despite these advances, fewer methods have been developed using red-light excitation, limiting the use of photoproximity labeling in more complex media such as tissues and animal models. Herein, we develop a platform for proximity labeling under red-light excitation, utilizing a single catalyst and two distinct probe types. We first design a carbene based labeling system that utilizes sulfonium diazo probes. This system is successfully applied on A549 cells to capture the interactome of epidermal growth factor receptor (EGFR) using a Cetuximab-Chlorin e6 conjugate. Benchmarking against established techniques indicates that this approach performs comparably to leading carbene-based proximity labeling methods. Next, we leverage the strong singlet oxygen generation (SOG) ability of Chlorin e6 to establish an alternative labeling system using aniline and hydrazide probes. EGFR directed chemoproteomics experiments reveal significant overlap with the carbene system, with the carbene approach capturing a subset of interactions identified by the SOG system. Finally, we deploy our approach for the characterization of EGFR in resected human glioblastoma (GBM) tissue samples removed from distinct locations in the same tumor, representing the tumor's infiltrating edge and its viable center, identifying several GBM specific interacting proteins that may serve as a launch point for future therapeutic campaigns.

Near-Infrared Light-Mediated Living Cells Mitochondrial Proteome Proximity Labeling

Photocatalytic proximity labeling techniques enable significant advances in understanding the subcellular proteome. However, current methods primarily utilize visible light that suffers from low labeling efficiency and limited identification coverage due to absorption overlap with endogenous chromophores and scattering in biological samples. To address these issues, we reported the proximity labeling strategy using near-infrared excitation (PL-NIR) strategy, a proximity labeling platform that used a near-infrared-excited catalyst to activate labeling mediated by reactive oxygen species, which could avoid the disadvantages of visible light. Taking advantage of the near-infrared excitation and mitochondrial targeting properties of IR780, the mitochondrial proteome were selectively labeled by spatially limited reaction in the native environment. The PL-NIR strategy facilitated the plotting of the mitochondrial proteome in which up to 245 mitochondrial proteins were identified in living HeLa cells. Compared with the current methods, the PL-NIR strategy significantly increased identification coverage, especially for mitochondrial inner membrane proteins. Furthermore, mitochondrial proteome dynamics were deciphered in LPS stimulated HMC3 cells, which were hard to transfect. Overall, the PL-NIR strategy as a highly precise proteomic platform offered improved identification coverage for more knowledge of subcellular biology discovering.

Approaching Two Decades: Biomolecular Coronas and Bio-Nano Interactions

It has been nearly two decades since the term "protein corona" was coined. This term has since evolved to "biomolecular corona" or "biocorona" to capture the diverse biomolecules that spontaneously form on the surface of nanoparticles upon exposure to biological fluids and drive nanoparticle interactions with biological systems. In this Perspective, we highlight the significant progress in this field, including studies on nonprotein corona components, lipid nanoparticles, and the role of the corona in endogenous organ targeting. We also discuss research opportunities in this field, particularly the need for improved characterization and standardization of analysis and how recent advances in artificial intelligence and ex vivo models can improve our understanding of the biomolecular corona in guiding nanomedicine design.

Proximal Anchoring of Nanodrugs through In Situ Generated Radical Hooks with Boosted Autophagy and Immunotherapy

Efficient retention of drugs at tumor sites was always desirable to maximize therapeutic functions, yet the main concern is the dynamic blood clearance induced fast removal from localized lesion. Herein, a tumor microenvironment activated covalently conjugation (self- and proximal conjugation) of tyramine modified Pt nanoclusters (PCMT NPs) was constructed by in situ produced radical hooks, leading to efficient accumulation of PCMT NPs at tumor sites. Such accumulation further aggravated the oxidative stress and provoked autophagy of tumor cells via activating the caspase-3 pathway mediated massive apoptosis, thereby stimulating immunogenic cell death (ICD). As verified by in vivo results, the PCMT NPs effectively suppressed primary and distant tumor growth (with an inhibition rate of 99%) while eliciting immunotherapeutic responses. As such, a new paradigm for boosting drug retention was provided, which enabled specific tumor treatment with synergistic therapeutic outcomes.

Understanding the role of biomolecular coronas in human exposure to nanomaterials

Nanomaterials (NMs) are increasingly used in medical treatments, electronics, and food additives. However, nanosafety-the possible adverse effects of NMs on human health-is an area of active research. This review provides an overview of the influence of biomolecular coronas on NM transformation following various exposure routes. We discuss potential exposure pathways, including inhalation and ingestion, describing the physiology of exposure routes and emphasising the relevance of coronas in these environments. Additionally, we review other routes to NM exposure, such as synovial fluid, blood (translocation and injection), dermal and ocular exposure, as well as the dose and medium impact on NM interactions. We emphasize the need for an in-depth characterisation of coronas in different biological media, highlighting the need and opportunity to study lung and gastric fluids to understand NM behaviour and potential toxicity. Future research aims to predict better in vivo outcomes and address the complexities of NM interactions with biological systems.

Protein Corona of Nanoparticles: Isolation and Analysis

Nanoparticles entering biological systems or fluids inevitably adsorb biomolecules, such as protein, on their surfaces, forming a protein corona. Ensuing, the protein corona endows nanoparticles with a new biological identity and impacts the interaction between the nanoparticles and biological systems. Hence, the development of reliable techniques for protein corona isolation and analysis is key for understanding the biological behaviors of nanoparticles. First, this review systematically outlines the approach for isolating the protein corona, including centrifugation, magnetic separation, size exclusion chromatography, flow-field-flow fractionation, and other emerging methods. Next, we review the qualitative and quantitative characterization methods of the protein corona. Finally, we underscore the necessary steps to advance the efficiency and fidelity of protein corona isolation and characterization on nanoparticle surfaces. We anticipate that these insights into protein corona isolation and characterization methodologies will profoundly influence the development of technologies aimed at elucidating bionano interactions and the role of protein corona in various biomedical applications.

Enhancing the Efficacy of Active Pharmaceutical Ingredients in Medicinal Plants through Nanoformulations: A Promising Field

This article explores the emerging field of nanomedicine as a drug delivery system, aimed at enhancing the therapeutic efficacy of active pharmaceutical ingredients in medicinal plants. The traditional methods of applying medicinal plants present several limitations, such as low bioavailability, poor solubility, challenges in accurately controlling drug dosage, and inadequate targeting. Nanoformulations represent an innovative approach in drug preparation that employs nanotechnology to produce nanoscale particles or carriers, which are designed to overcome these limitations. Nanoformulations offer distinct advantages, significantly enhancing the solubility and bioavailability of drugs, particularly for the poorly soluble components of medicinal plants. These formulations effectively enhance solubility, thereby facilitating better absorption and utilization by the human body, which in turn improves drug efficacy. Furthermore, nanomedicine enables targeted drug delivery, ensuring precise administration to the lesion site and minimizing side effects on healthy tissues. Additionally, nanoformulations can regulate drug release rates, extend the duration of therapeutic action, and enhance the stability of treatment effects. However, nanoformulations present certain limitations and potential risks; their stability and safety require further investigation, particularly regarding the potential toxicity with long-term use. Nevertheless, nanomaterials demonstrate substantial potential in augmenting the efficacy of active pharmaceutical ingredients in medicinal plants, offering novel approaches and methodologies for their development and application.

Physiological Barriers and Strategies of Lipid-Based Nanoparticles for Nucleic Acid Drug Delivery

Lipid-based nanoparticles (LBNPs) are currently the most promising vehicles for nucleic acid drug (NAD) delivery. Although their clinical applications have achieved success, the NAD delivery efficiency and safety are still unsatisfactory, which are, to a large extent, due to the existence of multi-level physiological barriers in vivo. It is important to elucidate the interactions between these barriers and LBNPs, which will guide more rational design of efficient NAD vehicles with low adverse effects and facilitate broader applications of nucleic acid therapeutics. This review describes the obstacles and challenges of biological barriers to NAD delivery at systemic, organ, sub-organ, cellular, and subcellular levels. The strategies to overcome these barriers are comprehensively reviewed, mainly including physically/chemically engineering LBNPs and directly modifying physiological barriers by auxiliary treatments. Then the potentials and challenges for successful translation of these preclinical studies into the clinic are discussed. In the end, a forward look at the strategies on manipulating protein corona (PC) is addressed, which may pull off the trick of overcoming those physiological barriers and significantly improve the efficacy and safety of LBNP-based NADs delivery.

Unveiling the challenges of engineered protein corona from the proteins' perspective

It is well known that protein corona affects the "biological identity" of nanoparticles (NPs), which has been seen as both a challenge and an opportunity. Approaches have moved from avoiding protein adsorption to trying to direct it, taking advantage of the formation of a protein corona to favorably modify the pharmacokinetic parameters of NPs. Although promising, the results obtained with engineered NPs still need to be completely understood. While much effort has been put into understanding how the surface of nanomaterials affects protein absorption, less is known about how proteins can affect corona formation due to their specific physicochemical properties. This review addresses this knowledge gap, examining key protein factors influencing corona formation, highlighting current challenges in studying protein-protein interactions, and discussing future perspectives in the field.

Molecular Mechanisms of Intracellular Delivery of Nanoparticles Monitored by an Enzyme-Induced Proximity Labeling

Achieving increasingly finely targeted drug delivery to organs, tissues, cells, and even to intracellular biomacromolecules is one of the core goals of nanomedicines. As the delivery destination is refined to cellular and subcellular targets, it is essential to explore the delivery of nanomedicines at the molecular level. However, due to the lack of technical methods, the molecular mechanism of the intracellular delivery of nanomedicines remains unclear to date. Here, we develop an enzyme-induced proximity labeling technology in nanoparticles (nano-EPL) for the real-time monitoring of proteins that interact with intracellular nanomedicines. Poly(lactic-co-glycolic acid) nanoparticles coupled with horseradish peroxidase (HRP) were fabricated as a model (HRP(+)-PNPs) to evaluate the molecular mechanism of nano delivery in macrophages. By adding the labeling probe biotin-phenol and the catalytic substrate H2O2 at different time points in cellular delivery, nano-EPL technology was validated for the real-time in situ labeling of proteins interacting with nanoparticles. Nano-EPL achieves the dynamic molecular profiling of 740 proteins to map the intracellular delivery of HRP (+)-PNPs in macrophages over time. Based on dynamic clustering analysis of these proteins, we further discovered that different organelles, including endosomes, lysosomes, the endoplasmic reticulum, and the Golgi apparatus, are involved in delivery with distinct participation timelines. More importantly, the engagement of these organelles differentially affects the drug delivery efficiency, reflecting the spatial-temporal heterogeneity of nano delivery in cells. In summary, these findings highlight a significant methodological advance toward understanding the molecular mechanisms involved in the intracellular delivery of nanomedicines.

Intratumor delivery of amino-modified graphene oxide as a multifunctional photothermal agent for efficient antitumor phototherapy

Due to the high selectivity and non-invasive property, phototherapy has attracted increasing attention in the treatment of cancer. Targeted delivery and retention of photoactive agents in tumor tissue is of great significance and importance for safe and efficient phototherapy. Herein, we report a multifunctional nanomaterial photothermal agent, namely amino-modified graphene oxide (AGO) for anti-oral cancer photothermal therapy (PTT). Compared to the parental graphene oxide (GO) which has a negative charge and weak photothermal effect, AGO possesses a positive charge (∼+50 mV) and the significantly enhanced photothermal effect. Positive charge allows AGO to efficiently interact with tumor cells and retain in tumor tissue after intratumor injection. The enhanced photothermal effect allows AGO to achieve the tunable and efficient PTT. In vitro results show that AGO (15 μg/mL) reduces the viability of HSC-3 cells (oral squamous cell carcinoma cell line) to 5% under near infrared (NIR) irradiation (temperature increased to 58.4 °C). In vivo antitumor study shows that intratumor delivery of AGO (200 μg/mouse) has no inhibition effects on tumor growth (454% of initial tumor size) without NIR. With a single dose of NIR irradiation, however, AGO significantly reduces the tumor size to 25% of initial size in 1 of 4 mice, and even induces the complete tumor ablation in 3 of 4 mice. Furthermore, the injected AGO falls off along with the scab after PTT. Our findings indicate that AGO is a potential nano-photothermal agent for tunable, convenient and efficient anticancer PTT.

Intelligent nanomaterials for cancer therapy: recent progresses and future possibilities

Intelligent nanomedicine is currently one of the most active frontiers in cancer therapy development. Empowered by the recent progresses of nanobiotechnology, a new generation of multifunctional nanotherapeutics and imaging platforms has remarkably improved our capability to cope with the highly heterogeneous and complicated nature of cancer. With rationally designed multifunctionality and programmable assembly of functional subunits, the in vivo behaviors of intelligent nanosystems have become increasingly tunable, making them more efficient in performing sophisticated actions in physiological and pathological microenvironments. In recent years, intelligent nanomaterial-based theranostic platforms have showed great potential in tumor-targeted delivery, biological barrier circumvention, multi-responsive tumor sensing and drug release, as well as convergence with precise medication approaches such as personalized tumor vaccines. On the other hand, the increasing system complexity of anti-cancer nanomedicines also pose significant challenges in characterization, monitoring and clinical use, requesting a more comprehensive and dynamic understanding of nano-bio interactions. This review aims to briefly summarize the recent progresses achieved by intelligent nanomaterials in tumor-targeted drug delivery, tumor immunotherapy and temporospatially specific tumor imaging, as well as important advances of our knowledge on their interaction with biological systems. In the perspective of clinical translation, we have further discussed the major possibilities provided by disease-oriented development of anti-cancer nanomaterials, highlighting the critical importance clinically-oriented system design.