The Fate of Intranasally Instilled Silver Nanoarchitectures.

The intranasal administration of drugs allows an effective and noninvasive therapeutic action on the respiratory tract. In an era of rapidly increasing antimicrobial resistance, new approaches to the treatment of communicable diseases, especially lung infections, are urgently needed. Metal nanoparticles are recognized as a potential last-line defense, but limited data on the biosafety and nano/biointeractions preclude their use. Here, we quantitatively and qualitatively assess the fate and the potential risks associated with the exposure to a silver nanomaterial model (i.e., silver ultrasmall-in-nano architectures, AgNAs) after a single dose instillation. Our results highlight that the biodistribution profile and the nano/biointeractions are critically influenced by both the design of the nanomaterial and the chemical nature of the metal. Overall, our data suggest that the instillation of rationally engineered nanomaterials might be exploited to develop future treatments for (non)communicable diseases of the respiratory tract.

High-performance biosensor exploiting a light guidance in sparse arrays of metal nanoparticles.

We introduce a new approach to plasmonic biosensing with superior biosensing properties based on spectroscopy of an electromagnetic mode guided by a monolayer of sparsely distributed colloidal plasmonic nanoparticles. The theoretical prediction of optical and sensing performance is confirmed by an experimental study in which adsorption of biomolecules on the sensor surface is studied. An unprecedentedly high figure of merit related to surface refractive index changes (FOMS) is demonstrated for distances of the biomolecules from the sensor surface up to 30 nm, which makes this approach a promising candidate for localized biosensing.

Functional gold nanoparticles for optical affinity biosensing.

Functional gold nanoparticles (AuNPs) are commonly used to enhance the response of optical affinity biosensors. In this work, we investigated the effect of preparation conditions on functional properties of AuNPs functionalized with antibody (Ab-AuNPs), specifically AuNPs with antibody against carcinoembryonic antigen (CEA) covalently attached via carboxy-terminated oligo-ethylene thiolate linker layer. The following parameters of preparation of Ab-AuNP have been found to have a significant effect on Ab-AuNP performance in affinity biosensors: the time of reaction of activated AuNPs with antibody, concentrations of antibody and amino-coupling reagents, and composition of immobilization buffer (molarity and salt content). In contrast, pH of immobilization buffer has been demonstrated to have only a minor influence. Our experiments showed that the Ab-AuNPs prepared under optimum conditions offered a binding efficiency of Ab-AuNPs to CEA as high as 63%, which is more than 4 times better than the best efficiencies reported for similar functional AuNPs so far. We employed these Ab-AuNPs with a surface plasmon resonance (SPR) biosensor for the detection of CEA and showed that the Ab-AuNPs enhanced the sensor response to CEA by a factor of 1000. We also demonstrated that the Ab-AuNPs allow the biosensor to detect CEA at concentrations as low as 12 and 40 pg/mL in buffer and 50% blood plasma, respectively.

Pregnancy-Associated Plasma Protein A2 in Hemodialysis Patients: Significance for Prognosis.

BACKGROUND: Pregnancy-associated plasma protein A (PAPP-A) is associated with adverse outcome of long-term hemodialysis patients (HD). The aim of the study was to test whether its homolog pregnancy-associated plasma protein A2 (PAPP-A2) can be detected in serum of HD patients and to define its significance. METHODS: The studied group consisted of 102 long-term HD patients and 25 healthy controls. HD patients were prospectively followed up for five years (2009-2014). PAPP-A2 was measured by surface plasmon resonance biosensor, PAPP-A by time resolved amplified cryptate emission. RESULTS: PAPP-A2, similarly as PAPP-A, was significantly increased in HD patients (median (interquartile range)) PAPP-A2: 6.2 (2.6-10.8) ng/mL, vs. 3.0 (0.7-5.9) ng/mL, p=0.006; PAPP-A: 18.9 (14.3-23.4) mIU/L, vs. 9.5 (8.4-10.5) mIU/L, p<0.001). In HD patients, PAPP-A2 correlated weakly but significantly with PAPP-A (τ=0.193, p=0.004). Unlike PAPP-A, PAPP-A2 was not significant for prognosis of HD patients when tested alone. There was a significant interaction between PAPP-A and PAPP-A2 on the mortality due to infection of HD patients (p=0.008). If PAPP-A was below median, mortality due to infection was significantly higher for patients with PAPP-A2 values above median than for patients with low PAPP-A2 levels (p=0.011). CONCLUSION: PAPP-A2 is increased in HD patients and interacts with PAPP-A on patients´ prognosis.

Copolymer Brush-Based Ultralow-Fouling Biorecognition Surface Platform for Food Safety.

Functional polymer coatings that combine the ability to resist nonspecific fouling from complex media with high biorecognition element (BRE) immobilization capacity represent an emerging class of new functional materials for a number of bioanalytical and biosensor technologies for medical diagnostics, security, and food safety. Here, we report on a random copolymer brush surface - poly(CBMAA-ran-HPMAA) - providing high BRE immobilization capacity while simultaneously exhibiting ultralow-fouling behavior in complex food media. We demonstrate that both the functionalization and fouling resistance capabilities of such copolymer brushes can be tuned by changing the surface contents of the two monomer units: nonionic N-(2-hydroxypropyl) methacrylamide (HPMAA) and carboxy-functional zwitterionic carboxybetaine methacrylamide (CBMAA). It is demonstrated that the resistance to fouling decreases with the surface content of CBMAA; poly(CBMAA-ran-HPMAA) brushes with CBMAA molar content up to 15 mol % maintain excellent resistance to fouling from a variety of homogenized foods (hamburger, cucumber, milk, and lettuce) even after covalent attachment of BREs to carboxy groups of CBMAA. The poly(CBMAA 15 mol %-ran-HPMAA) brushes functionalized with antibodies are demonstrated to exhibit fouling resistance from food samples by up to 3 orders of magnitude better when compared with the widely used low-fouling carboxy-functional oligo(ethylene glycol) (OEG)-based alkanethiolate self-assembled monolayers (AT SAMs) and, furthermore, by up to 2 orders of magnitude better when compared with the most successful ultralow-fouling biorecognition coatings - poly(carboxybetaine acrylamide), poly(CBAA). When model SPR detections of food-borne bacterial pathogens in homogenized foods are used, it is also demonstrated that the antibody-functionalized poly(CBMAA 15 mol %-ran-HPMAA) brush exhibits superior biorecognition properties over the poly(CBAA).

Enhancing sensitivity of surface plasmon resonance biosensors by functionalized gold nanoparticles: size matters.

We study how the size of spherical gold nanoparticles (AuNPs) influences their ability to enhance the response of optical biosensors based on surface plasmon resonance (SPR). We present a theoretical model that relates the enhancement generated by the AuNPs to their composition, size, and concentration, thus allowing for accurate predictions regarding the SPR sensor response to various AuNPs. The effect of the AuNP size is also investigated experimentally using an SPR biosensor for the detection of carcinoembryonic antigen (CEA) in which AuNPs covered with neutravidin (N-AuNPs) are used in the last step of a sandwich assay to enhance the sensor response to biotinylated secondary antibody against CEA. The experimental data are in excellent agreement with the results of the theoretical analysis. We demonstrate that the sensor response enhancement generated by the N-AuNPs is determined by (i) the sensor sensitivity to N-AuNP surface density (Sσ) and (ii) the ability of the N-AuNPs to bind to the functionalized surface of the sensor. Our results indicate that, while Sσ increases with the size of the N-AuNP, the ability of the functionalized surface of the sensor to bind the N-AuNPs is affected by steric effects and decreases with the size of N-AuNP.

A bioconvergence study on platinum-free concurrent chemoradiotherapy for the treatment of HPV-negative head and neck carcinoma.

Locally advanced head and neck squamous cell carcinoma (LA-HNSCC) is characterized by high rate of recurrence, resulting in a poor survival. Standard treatments are associated with significant toxicities that impact the patient's quality of life, highlighting the urgent need for novel therapies to improve patient outcomes. On this regard, noble metal nanoparticles (NPs) are emerging as promising agents as both drug carriers and radiosensitizers. On the other hand, co-treatments based on NPs are still at the preclinical stage because of the associated metal-persistence.In this bioconvergence study, we introduce a novel strategy to exploit tumour chorioallantoic membrane models (CAMs) in radio-investigations within clinical equipment and evaluate the performance of non-persistent nanoarchitectures (NAs) in combination with radiotherapy with respect to the standard concurrent chemoradiotherapy for the treatment of HPV-negative HNSCCs. A comparable effect has been observed between the tested approaches, suggesting NAs as a potential platinum-free agent in concurrent chemoradiotherapy for HNSCCs. On a broader basis, our bioconvergence approach provides an advance for the translation of Pt-free radiosensitizer to the clinical practice, positively shifting the therapeutic vs. side effects equilibrium for the management of HNSCCs.

Nonpersistent Nanoarchitectures Enhance Concurrent Chemoradiotherapy in an Immunocompetent Orthotopic Model of HPV+ Head/Neck Carcinoma.

Cisplatin chemoradiotherapy (CRT) is the established standard of care for managing locally advanced human papillomavirus-positive head/neck carcinoma. The typically young patients may suffer serious and long-time side effects caused by the treatment, such as dysphagia, and hearing loss. Thus, ensuring a satisfactory post-treatment quality of life is paramount. One potential replacing approach to the classical CRT involves the combination of standard-dose radiotherapy and radiosensitizers such as noble metal nanoparticles (NPs). However, several concerns about size, shape, and biocompatibility limit the translation of metal nanomaterials to the clinical practice. Here, it is demonstrated that a new model of nonpersistent gold nanoarchitectures containing cisplatin (NAs-Cluster-CisPt) generates, in combination with radiotherapy, a significant in vivo tumor-reducing effect compared to the standard CRT, achieving a complete tumor clearance in 25% of the immunocompetent models that persist for 60 days. These findings, together with the negligible amount of metals recognized in the excretory organs, highlight that the concurrent administration of NAs-Cluster-CisPt and radiotherapy has the potential to overcome some clinical limitations associated to NP-based approaches while enhancing the treatment outcome with respect to standard CRT. Overall, despite further mechanistic investigations being essential, these data support the exploiting of nonpersistent metal-nanomaterial-mediated approaches for oral cancer management.

Copper nano-architecture topical cream for the accelerated recovery of burnt skin.

Skin burns are debilitating injuries with significant morbidity and mortality associated with infections and sepsis, particularly in immunocompromised patients. In this context, nanotechnology can provide pioneering approaches for the topical treatment of burnt skin. Herein, the significant recovery of radiation-damaged skin by exploiting copper ultrasmall-in-nano architectures (CuNAs) dispersed in a home-made cosmetic cream is described and compared to other noble metals (such as gold). Owing to their peculiar design and components, CuNAs elicit a substantial recovery from burned skin in in vivo models after one topical application, and a significant anti-inflammatory effect is highlighted by reducing cytokine expression. The treatment exhibited neither significant toxicity nor the alteration of copper metabolism in the target organs because of the CuNA biocompatibility. This study may open new horizons in the treatment of radiation dermatitis and skin burns caused by other external events.

Hybrid nano-architectures loaded with metal complexes for the co-chemotherapy of head and neck carcinomas.

Head and neck squamous cell carcinomas (HNSCCs) are a complex group of malignancies that affect different body sites pertaining to the oral cavity, pharynx and larynx. Current chemotherapy relies on platinum complexes, the major exponent being cisplatin, which exert severe side effects that can negatively affect prognosis. For this reason, other metal complexes with less severe side effects are being investigated as alternatives or adjuvants to platinum complexes. In this context, exploiting (supra)additive effects by the concurrent administration of cisplatin and emerging metal complexes is a promising research strategy that may lead to effective cancer management with reduced adverse reactions. Here, the combined action of cisplatin and a ruthenium(II) η6-arene compound (RuCy), both as free molecules and loaded into hybrid nano-architectures (NAs), has been assessed on HPV-negative HNSCC models of increasing complexity: 2D cell cultures, 3D multicellular tumor spheroids, and chorioallantoic membranes (CAMs). Two new NAs have been established to explore all the delivery combinations and compare their ability to enhance the efficacy of cisplatin in the treatment of HNSCCs. A significant supra-additive effect has been observed in both 2D and 3D models by one combination of treatments, suggesting that cisplatin is particularly effective when loaded on NAs, whereas RuCy performs better when administered as a free compound. Overall, this work paves the way for the establishment of the next co-chemotherapeutic approaches for the management of HNSCCs.

Evolving approaches in glioma treatment: harnessing the potential of copper metabolism modulation.

The key properties and high versatility of metal nanoparticles have shed new perspectives on cancer therapy, with copper nanoparticles gaining great interest because of the ability to couple the intrinsic properties of metal nanoparticles with the biological activities of copper ions in cancer cells. Copper, indeed, is a cofactor involved in different metabolic pathways of many physiological and pathological processes. Literature data report on the use of copper in preclinical protocols for cancer treatment based on chemo-, photothermal-, or copper chelating-therapies. Copper nanoparticles exhibit anticancer activity via multiple routes, mainly involving the targeting of mitochondria, the modulation of oxidative stress, the induction of apoptosis and autophagy, and the modulation of immune response. Moreover, compared to other metal nanoparticles (e.g. gold, silver, palladium, and platinum), copper nanoparticles are rapidly cleared from organs with low systemic toxicity and benefit from the copper's low cost and wide availability. Within this review, we aim to explore the impact of copper in cancer research, focusing on glioma, the most common primary brain tumour. Glioma accounts for about 80% of all malignant brain tumours and shows a poor prognosis with the five-year survival rate being less than 5%. After introducing the glioma pathogenesis and the limitation of current therapeutic strategies, we will discuss the potential impact of copper therapy and present the key results of the most relevant literature to establish a reliable foundation for future development of copper-based approaches.

Organic Selenium induces ferroptosis in pancreatic cancer cells.

Pancreatic ductal adenocarcinoma (PDA) cells reprogram both mitochondrial and lysosomal functions to support growth. At the same time, this causes significant dishomeostasis of free radicals. While this is compensated by the upregulation of detoxification mechanisms, it also represents a potential vulnerability. Here we demonstrate that PDA cells are sensitive to the inhibition of the mevalonate pathway (MVP), which supports the biosynthesis of critical antioxidant intermediates and protect from ferroptosis. We attacked the susceptibility of PDA cells to ferroptotic death with selenorganic compounds, including dibenzyl diselenide (DBDS) that exhibits potent pro-oxidant properties and inhibits tumor growth in vitro and in vivo. DBDS treatment induces the mobilization of iron from mitochondria enabling uncontrolled lipid peroxidation. Finally, we showed that DBDS and statins act synergistically to promote ferroptosis and provide evidence that combined treatment is a viable strategy to combat PDA.

Pro-apoptotic and size-reducing effects of protein corona-modulating nano-architectures enclosing platinum prodrug in in vivo oral carcinoma.

The selective and localized delivery of active agents to neoplasms is crucial to enhance the chemotherapeutic efficacy while reducing the associated side effects. The encapsulation of chemotherapeutics in nanoparticles decorated with targeting agents is a strategy of special interest to improve drug delivery. However, serum protein adsorption often compromises the in vivo efficiency of targeting agents, leading to protein corona formation that interferes with the targeting process. Here, the enhanced efficacy of hybrid nano-architectures enclosing a platinum prodrug and decorated with a customized peptide (NAs-cisPt-Tf2) is demonstrated by employing alternative in vivo models of oral carcinoma. The peptide binds to transferrin and modulates the protein corona formation on NAs-cisPt-Tf2, supporting the identification of its receptor. Optimized chorioallantoic membrane cancer models (CAMs) enabled a thorough assessment of the tumor-suppressing effect of NAs-cisPt-Tf2 as well as the quantitative evaluation of angiogenesis and cell cycle associated mechanisms. The treatment strategy resulted in a significant tumor volume reduction coupled with anti-angiogenic and pro-apoptotic effects inferred from the downregulation of the vascular endothelial growth factor gene and increased expression of cleaved caspase-3. Overall, this study provides a potentially effective tumor-targeted approach for a non-invasive management of oral carcinoma.

Chorioallantoic membrane tumor models highlight the effects of cisplatin compounds in oral carcinoma treatment.

The European Society for Medical Oncology (ESMO) suggests the use of chemotherapy as neoadjuvant, adjuvant, and concomitant to surgery and radiotherapy for the treatment of oral carcinoma by depending on the cancer stage. The usual drug of choice belongs to the platinum compounds. In this context, the evaluation of the cancer behavior associated with the administration of standard or emerging cisplatin compounds supports the establishment of optimal cancer management. Here, we have assessed and compared the performance of cisplatin alone and contained in biodegradable nanocapsules on standardized chorioallantoic membrane (CAM) tumor models. The vascularized environment and optimized grafting procedure allowed the establishment of solid tumors. The treatments showed antitumor and anti-angiogenic activities together with deregulation of pivotal genes responsible of treatment resistance and tumor aggressiveness. This study further supports the significance of CAM tumor models in oncological research for the comprehension of the molecular mechanisms involved in tumor treatment response.

Biodegradable Ultrasmall-in-Nano Architectures Loaded with Cisplatin Prodrug in Combination with Ionizing Radiation Induces DNA Damage and Apoptosis in Pancreatic Ductal Adenocarcinoma.

Considering the dismal survival rate, novel therapeutic strategies are warranted to improve the outcome of pancreatic ductal adenocarcinoma (PDAC). Combining nanotechnology for delivery of chemotherapeutics-preferably radiosensitizing agents-is a promising approach to enhance the therapeutic efficacy of chemoradiation. We assessed the effect of biodegradable ultrasmall-in-nano architectures (NAs) containing gold ultra-small nanoparticles (USNPs) enclosed in silica shells loaded with cisplatin prodrug (NAs-cisPt) combined with ionizing radiation (IR). The cytotoxic effects and DNA damage induction were evaluated in PDAC cell lines (MIA PaCa2, SUIT2-028) and primary culture (PDAC3) in vitro and in the chorioallantoic membrane (CAM) in ovo model. Unlike NAs, NAs-cisPt affected the cell viability in MIA PaCa2 and SUIT2-028 cells. Furthermore, NAs-cisPt showed increased γH2AX expression up to 24 h post-IR and reduced ß-globin amplifications resulting in apoptosis induction at DNA and protein levels. Similarly, combined treatment of NAs-cisPt + IR in PDAC3 and SUIT2-028 CAM models showed enhanced DNA damage and apoptosis leading to tumor growth delay. Our results demonstrate an increased cytotoxic effect of NAs-cisPt, particularly through its release of the cisplatin prodrug. As cisplatin is a well-known radiosensitizer, administration of cisplatin prodrug in a controlled fashion through encapsulation is a promising new treatment approach which merits further investigation in combination with other radiosensitizing agents.

Simultaneous detection of transgenic DNA by surface plasmon resonance imaging with potential application to gene doping detection.

Surface plasmon resonance imaging (SPRi) was used as the transduction principle for the development of optical-based sensing for transgenes detection in human cell lines. The objective was to develop a multianalyte, label-free, and real-time approach for DNA sequences that are identified as markers of transgenosis events. The strategy exploits SPRi sensing to detect the transgenic event by targeting selected marker sequences, which are present on shuttle vector backbone used to carry out the transfection of human embryonic kidney (HEK) cell lines. Here, we identified DNA sequences belonging to the Cytomegalovirus promoter and the Enhanced Green Fluorescent Protein gene. System development is discussed in terms of probe efficiency and influence of secondary structures on biorecognition reaction on sensor; moreover, optimization of PCR samples pretreatment was carried out to allow hybridization on biosensor, together with an approach to increase SPRi signals by in situ mass enhancement. Real-time PCR was also employed as reference technique for marker sequences detection on human HEK cells. We can foresee that the developed system may have potential applications in the field of antidoping research focused on the so-called gene doping.

Antimicrobial Nano-Agents: The Copper Age.

The constant advent of major health threats such as antibacterial resistance or highly communicable viruses, together with a declining antimicrobial discovery, urgently requires the exploration of innovative therapeutic approaches. Nowadays, strategies based on metal nanoparticle technology have demonstrated interesting outcomes due to their intrinsic features. In this scenario, there is an emerging and growing interest in copper-based nanoparticles (CuNPs). Indeed, in their pure metallic form, as oxides, or in combination with sulfur, CuNPs have peculiar behaviors that result in effective antimicrobial activity associated with the stimulation of essential body functions. Here, we present a critical review on the state of the art regarding the in vitro and in vivo evaluations of the antimicrobial activity of CuNPs together with absorption, distribution, metabolism, excretion, and toxicity (ADMET) assessments. Considering the potentiality of CuNPs in antimicrobial treatments, within this Review we encounter the need to summarize the behaviors of CuNPs and provide the expected perspectives on their contributions to infectious and communicable disease management.

Complementary Effect of Non-Persistent Silver Nano-Architectures and Chlorhexidine on Infected Wound Healing.

Surgical site infection (SSI) substantially contributes each year to patients' morbidity and mortality, accounting for about 15% of all nosocomial infections. SSI drastically increases the rehab stint and expenses while jeopardizing health outcomes. Besides prevention, the treatment regime relies on an adequate antibiotic therapy. On the other hand, resistant bacterial strains have currently reached up to 34.3% of the total infections, and this percentage grows annually, reducing the efficacy of the common treatment schemes. Thus, new antibacterial strategies are urgently demanded. Here, we demonstrated in rats the effectiveness of non-persistent silver nano-architectures (AgNAs) in infected wound healing together with their synergistic action in combination with chlorhexidine. Besides the in vivo efficacy evaluation, we performed analysis of the bacteriological profile of purulent wound, histological evaluations, and macrophages polarization quantifications to further validate our findings and elucidate the possible mechanisms of AgNAs action on wound healing. These findings open the way for the composition of robust multifunctional nanoplatforms for the translation of safe and efficient topical treatments of SSI.

A Cost-Effective Approach for Non-Persistent Gold Nano-Architectures Production.

The effective exploitation of the intriguing theranostic features of noble metal nanoparticles for therapeutic applications is far from being a routine practice due to the persistence issue. In this regard, passion fruit-like nano-architectures (NAs), biodegradable and excretable all-in-one, nature-inspired platforms which jointly combine these characteristics with the appealing optical behaviors of noble metal nanoparticles, can offer a new alternative for theranostic applications. Besides the need for efficacious and innovative systems, the reliable and cost-effective production of nanomaterials is a pivotal subject for their translation to the clinical setting. Here, we demonstrate the production of a new cheaper class of degradable, ultrasmall-in-nano-architectures (dragon fruit NAs, dNAs) using polyethyleneimine (PEI) as a cationic polymer without affecting either their compositions or their physiological behaviors, compared to the previous NAs. In particular, the standardized protocol characterized in this work ensures the preparation of high gold-loading capacity nanoparticles, a peculiar characteristic that, synergically with the interesting properties of PEI, may unlock new possible applications previously precluded to the first version of NAs while reducing the hand-made production cost by three orders of magnitude.

Biokinetics and clearance of inhaled gold ultrasmall-in-nano architectures.

Among an organism's entry portals, the respiratory tract is one of the most promising routes for non-invasive administration of therapeutics for local and systemic delivery. On the other hand, it is the subtlest to protect from environmental pollution and microbial occurrences. Here, the biokinetics, distribution, and clearance trends of gold ultrasmall-in-nano architectures administered through a single intranasal application have been quantitatively evaluated. Apart from reaching the lung parenchyma, the (bio)degradable nano-architectures are able to translocate as well to secondary organs and be almost completely excreted within 10 days. These findings further support the clinical relevance of plasmonic nanomaterials for oncology and infectious disease treatment and management. Notably, this investigation also provides crucial information regarding the associated risks as a consequence of the pulmonary delivery of nanoparticles.