Shielding against breast tumor relapse with an autologous chemo-photo-immune active Nano-Micro-Sera based fibrin implant.

Local recurrence post-surgery in early-stage triple-negative breast cancer is a major challenge. To control the regrowth of a residual tumor, we have developed an autologous therapeutic hybrid fibrin glue for intra-operative implantation. Using autologous serum proteins as stabilizers, we have optimized high drug-loaded lapatinib-NanoSera (Lap-NS; ∼66% L.C.) and imiquimod-MicroSera (IMQ-MS; ∼92% L.C). Additionally, plasmonic nanosera (PNS) with an ∼67% photothermal conversion efficiency under 980 nm laser irradiation was also developed. While localized monotherapy with either Lap-NS or PNS reduced the tumor regrowth rate, their combination with IMQ-MS amplified the effect of immunogenic cell death with a high level of tumor infiltration by immune cells at the surgical site. The localized combination immunotherapy with a Nano-MicroSera based hybrid fibrin implant showed superior tumor inhibition and survival with significant promise for clinical translation.

BODIPY directed one-dimensional self-assembly of gold nanorods.

The assembly of anisotropic nanomaterials into ordered structures is challenging. Nevertheless, such self-assembled systems are known to have novel physicochemical properties and the presence of a chromophore within the nanoparticle ensemble can enhance the optical properties through plasmon-molecule electronic coupling. Here, we report the end-to-end assembly of gold nanorods into micrometer-long chains using a linear diamino BODIPY derivative. The preferential binding affinity of the amino group and the steric bulkiness of BODIPY directed the longitudinal assembly of gold nanorods. As a result of the linear assembly, the BODIPY chromophores positioned themselves in the plasmonic hotspots, which resulted in efficient plasmon-molecule coupling, thereby imparting photothermal properties to the assembled nanorods. This work thus demonstrates a new approach for the linear assembly of gold nanorods resulting in a plasmon-molecule coupled system, and the synergy between self-assembly and electronic coupling resulted in an efficient system having potential biomedical applications.

Self-Assembled Nanobiomaterials for Combination Immunotherapy.

Nanotechnological interventions for cancer immunotherapy are a rapidly evolving paradigm with immense potential. Self-assembled nanobiomaterials present safer alternatives to their nondegradable counterparts and pose better functionalities in terms of controlled drug delivery and phototherapy to activate immunogenic cell death. In this Review, we discuss several classes of self-assembled nanobiomaterials based on polymers, lipids, peptides, hydrogel, metal organic frameworks, and covalent-organic frameworks with the ability to activate systemic immune response and convert a "cold" immunosuppressive tumor mass to a "hot" antitumor immune cell rich microenvironment. The unique aspects of these materials are underpinned, and their mechanisms of combinatorial immunotherapeutic action are discussed. Future challenges associated with their clinical translation are also highlighted.

Design of Silica@Au Hybrid Nanostars for Enhanced SERS and Photothermal Effect.

Core-shell nanostructures of silicon oxide@noble metal have drawn a lot of interest due to their distinctive characteristics and minimal toxicity with remarkable biocompatibility. Due to the unique property of localized surface plasmon resonance (LSPR), plasmonic nanoparticles are being used as surface-enhanced Raman scattering (SERS) based detection of pollutants and photothermal (PT) agents in cancer therapy. Herein, we demonstrate the synthesis of multifunctional silica core - Au nanostars shell (SiO2 @Au NSs) nanostructures using surfactant free aqueous phase method. The SERS performance of the as-synthesized anisotropic core-shell NSs was examined using Rhodamine B (RhB) dye as a Raman probe and resulted in strong enhancement factor of 1.37×106 . Furthermore, SiO2 @Au NSs were also employed for PT killing of breast cancer cells and they exhibited a concentration-dependent increase in the photothermal effect. The SiO2 @Au NSs show remarkable photothermal conversion efficiency of up to 72 % which is unprecedented. As an outcome, our synthesized NIR active SiO2 @Au NSs are of pivotal importance to have their dual applications in SERS enhancement and PT effect.

Preclinical safety assessment of photoluminescent metal quantum clusters stabilized with autologous serum proteins for host specific theranostics.

Host derived serum proteome stabilised red-emitting gold quantum clusters (or Au-QC-NanoSera or QCNS) of size range ~2 nm have been synthesised in a first reported study. The host serum was taken from bovine, murine and human origins to establish the proof of concept. In-vitro biocompatibility with normal murine L929 fibroblast cells and radiosensitisation ability against PLC/PRF/5 hepatoma cells was established. A concentration dependant radiosensitisation effect of QCNS at differential γ-radiation doses was observed with almost 90% killing of cancer cells at a radiation dose of 5Gy. Acute and subacute safety, and non-immunogenicity of autologously derived QCNS was established in in-bred C57BL/6 mice. The biodistribution analysis revealed that the QCNS were effectively cleared from the body over a course of 28 days and were found to pose no major threat to the proper functioning and morphology of the mice.

Glycol chitosan stabilized nanomedicine of lapatinib and doxorubicin for the management of metastatic breast tumor.

Advanced breast cancer is known to be highly evasive to conventional therapeutic regimes with a 5-year survival rate of less than 30% compared to over 90% for early stages. Although several new approaches are being explored to improve the survival outcome, there is still some room for equipping existing drugs such as lapatinib (LAPA) and doxorubicin (DOX) to fight the systemic disease. LAPA is associated with poorer clinical outcomes in HER2-negative patients. However its ability to also target EGFR has warranted its use in recent clinical trials. Nevertheless, the drug is poorly absorbed post oral administration and possess low aqueous solubility. DOX on the other hand is avoided in vulnerable patients in advanced stages due to its pronounced off-target toxicity. To overcome the pitfalls of the drugs, we have fabricated a nanomedicine co-loaded with LAPA & DOX and stabilized with glycol chitosan, a biocompatible polyelectrolyte. With a loading content of ~ 11.5% and ~ 15% respectively, LAPA and DOX in a single nanomedicine showed synergistic action against triple-negative breast cancer cells in comparison to physically mixed free drugs. The nanomedicine showed a time-dependent association with cancer cells thereon inducing apoptosis leading to ~ 80% cell death. The nanomedicine was found to be acutely safe in healthy Balb/c mice and could negate DOX-induced cardio toxicity. The combination nanomedicine significantly inhibited both the primary 4T1 breast tumor and its spread to the lung, liver, heart, and kidney compared to pristine drug controls. These preliminary data indicate bright prospects for the nanomedicine to be effective against metastatic breast cancer.

A visible-light activated ROS generator multilayer film for antibacterial coatings.

The current scenario of antibiotic-resistant bacteria and pandemics caused by viruses makes research in the area of antibacterial and antiviral materials and surfaces more urgent than ever. In this regard, salicylideneimine based tetracoordinate boron-containing organic compounds are emerging as a new class of photosensitizers for singlet oxygen generation. However, the inherent inability of small organic molecules to be processed limits their potential use in functional coatings. Here we show the synthesis of a novel polymer functionalized with diiodosalicylideneimine-boron difluoride (PEI-BF2) and its utility for surface coating inside glass vials via layer-by-layer (LbL) assembly. The multilayer thin films are characterized using AFM and UV-Vis spectroscopy and the resultant coatings display excellent stability. The multilayer coating could be activated using visible light, and owing to the photocatalytic activity of the incorporated PEI-BF2, the surface coating is able to generate singlet oxygen efficiently upon light irradiation. Further, the multilayer coated surfaces exhibit remarkable antimicrobial activity towards both Gram-positive and Gram-negative bacteria under a variety of conditions. Thus, owing to the simple synthesis and the convenient methodology adopted for the preparation of multilayer coatings, the material reported here could pave the way for the development of sunlight activated large area self-sterile surfaces.

High Drug Loading Nanoparticles Stabilized with Autologous Serum Proteins Passively Inhibits Tumor Growth.

We report drug nanocrystals stabilized with host-specific serum proteins with high loading (∼63% w/w). The human serum derived curcumin nanoparticles (Cur-NanoSera) showed superior in vitro anticancer efficiency compared to a free drug with substantial hemocompatibility. The preadsorbed protein coating impeded further protein corona formation, even with repeated serum exposures. Acute and subacute toxicity evaluations post single and dual injections of C57BL/6 mice indicated that Cur-NanoSera showed no prominent inflammatory response or organ damage in the in-bred mice. Passive accumulation of Cur-NanoSera in tumor tissue significantly suppressed its growth in a syngeneic breast tumor model in addition to controlling tumor burden associated splenomegaly.

Nontoxic In Vivo Clearable Nanoparticle Clusters for Theranostic Applications.

Disintegrable inorganic nanoclusters (GIONs) with gold seed (GS) coating of an iron oxide core with a primary nanoparticle size less than 6 nm were prepared for theranostic applications. The GIONs possessed a broad near-infrared (NIR) absorbance at ∼750 nm because of plasmon coupling between closely positioned GSs on the iron oxide nanoclusters (ION) surface, in addition to the ∼513 nm peak corresponding to the isolated GS. The NIR laser-triggered photothermal response of GIONs was found to be concentration-dependent with a temperature rise of ∼8.5 and ∼4.5 °C from physiological temperature for 0.5 and 0.25 mg/mL, respectively. The nanoclusters were nonhemolytic and showed compatibility with human umbilical vein endothelial cells up to a concentration of 0.7 mg/mL under physiological conditions. The nanoclusters completely disintegrated at a lysosomal pH of 5.2 within 1 month. With an acute increase of over 400% intracellular reactive oxygen species soon after γ-irradiation and assistance from Fenton reaction-mediated supplemental oxidative stress, GION treatment in conjunction with radiation killed ∼50% of PLC/PRF/5 hepatoma cells. Confocal microscopy images of these cells showed significant cytoskeletal and nuclear damage from radiosensitization with GIONs. The cell viability further decreased to ∼10% when they were sequentially exposed to the NIR laser followed by γ-irradiation. The magnetic and optical properties of the nanoclusters enabled GIONs to possess a T2 relaxivity of ∼223 mM-1 s-1and a concentration-dependent strong photoacoustic signal toward magnetic resonance and optical imaging. GIONs did not incur any organ damage or evoke an acute inflammatory response in healthy C57BL/6 mice. Elemental analysis of various organs indicated differential clearance of gold and iron via both renal and hepatobiliary routes.

Biodegradable Protein-Stabilized Inorganic Nanoassemblies for Photothermal Radiotherapy of Hepatoma Cells.

Inorganic nanomaterials require optimal engineering to retain their functionality yet can also biodegrade within physiological conditions to avoid chronic accumulation in their native form. In this work, we have developed gelatin-stabilized iron oxide nanoclusters having a primary crystallite size of ∼10 nm and surface-functionalized with indocyanine green (ICG)-bound albumin-stabilized gold nanoclusters (Prot-IONs). The Prot-IONs are designed to undergo disintegration in an acidic microenvironment of tumor in the presence of proteolytic enzymes within 72 h. These nanoassemblies demonstrate bio- and hemocompatibility and show significant photothermal efficiency due to strong near infrared absorption contributed by ICG. The surface gold nanoclusters could efficiently sensitize hepatoma cells to γ-irradiation with substantial cytoskeletal and nuclear damage. Sequential irradiation of Prot-ION-treated cancer cells with near infrared (NIR) laser (λ = 750 nm) and γ-irradiation could cause ∼90% cell death compared to single treatment groups at a lower dose of nanoparticles. The superparamagnetic nature of Prot-IONs imparted significant relaxivity (∼225 mM-1 s-1) for T2-weighted magnetic resonance imaging. Additionally, they could also be engaged as photoacoustic and NIR imaging contrast agents. This work demonstrates bioeliminable inorganic nanoassemblies with significant theranostic potential.

Nontoxic Metal-Free Visible Light-Responsive Carbon Nitride Quantum Dots Cause Oxidative Stress and Cancer-Specific Membrane Damage.

Graphitic carbon nitride (also known as g-CN or g-C3N4) has the intrinsic ability to generate electron-hole pairs under visible light illumination, resulting in the generation of reactive oxygen species (ROS). We report g-CN quantum dots (g-CNQDs) as a standalone photodynamic transducer for imparting significant oxidative stress in glioma cells, manifested by the loss of mitochondrial membrane potential. With an optimized treatment time, visible light source, and exposure window, the photodynamic treatment with g-CNQDs could achieve ∼90% cancer cell death via apoptosis. The g-CNQDs, otherwise biocompatible with normal cells up to 5 mg/mL, showed ∼20% necrotic cancer cell death in the absence of light due to membrane damage induced by a charge shielding effect at the acidic pH prevailing in the tumor environment. Acute toxicity analysis in C57BL/6 mice with intravenously injected g-CNQDs at a 20 mg/kg dose showed no signs of inflammatory response or organ damage.

Taking leads out of nature, can nano deliver us from COVID-like pandemics?

The COVID-19 crisis has alerted the research community to re-purpose scientific tools that can effectively manage emergency pandemic situations. Researchers were never so desperate to discover a 'magic bullet' that has significant clinical benefits with minimal or no side effects. At the beginning of the pandemic, due to restricted access to traditional laboratory techniques, many research groups delved into computational screening of thousands of lead molecules that could inhibit SARS-CoV-2 at one or more stages of its infectious cycle. Severalin silicostudies on natural derivatives point out their potency against SARS-CoV-2 proteins. However, theoretical predictions and existing knowledge on related molecules reflect their poor oral bioavailability due to biotransformation in the gut and liver. Nanotechnology has evolved into a key field for precise and controlled delivery of various drugs that lack aqueous solubility, have low oral bioavailability and possess pronounced toxicity in their native form. In this review, we discuss various nanoformulations of natural products with favorable ADME properties, and also briefly explore nano-drug delivery to lungs, the primary site of SARS-CoV-2 infection. Natural products are also envisioned to augment nanotechnology-based (1) personnel protective equipment forex vivoviral inactivation and (2) wearable sensors that perform rapid and non-invasive analysis of volatile organic compounds in exhaled breath of the infected person after therapeutic food consumption.

Microwave mediated synthesis of dopamine functionalized copper sulphide nanoparticles: An effective catalyst for visible light driven degradation of methlyene blue dye.

The current work highlights the potential aptitude of copper sulphide (CuS) nanoparticles as cost and energy-effective photo-catalyst for degrading methlyene blue dye under visible light. The surface modified CuS nanoparticles with dopamine (DOP) were prepared by using fast and cost effective microwave assisted methodology. Here, DOP act as biological ligand for the reduction and capping of CuS nanoparticles. The structural and morphological analyses revealed the size controlled synthesis of CuS in presence of DOP with higher thermal stability. The bio-compatibility and non-toxic behaviour of CuS@DOP nanoparticles was evaluated against L929 cell lines and on E. coli and S. aureus strains. The visible light driven photocatalytic activity of the synthesized CuS@DOP was scrutinized for the degradation of methylene blue (MB) dyes, as a model of water contaminants. The photocatalytic degradation of MB by CuS@DOP attained 97% after 10 min of visible light irradiation. The effect of catalyst dose, pH, initial concentration of MB dye, electrolytes, contact time, synergic effect of photolysis and catalysis were studied in detail for optimizing the degradation efficiency of CuS@DOP. The mechanism of CuS@DOP photocatalysis and the formed degraded products were analyzed by using LC/MS technique. The reusability and stability of photocatalyst was confirmed by reusing the catalyst for six successive runs with catalytic performance as high as 80%. Thus, CuS@DOP NPs acted as cost effective, non-toxic visible light driven photo-catalyst for the degradation of organic dye from waste water.

Natural derivatives with dual binding potential against SARS-CoV-2 main protease and human ACE2 possess low oral bioavailability: a brief computational analysis.

The world is witnessing severe health meltdown due to COVID-19. Generic antiviral drug remdesivir has been found to reduce time to clinical recovery but with insignificant clinical benefits and the antimalarial drug, hydroxychloroquine has been red flagged by USFDA for use as a prophylactic measure due to its cardiotoxicity. There is an acute requirement for a drug candidate that has significant clinical benefit with minimal to no side effects. With restricted access to wet laboratory techniques, an alternative approach is to engage in computational screening of lead molecules that could inhibit SARS-CoV-2 at different stages of its infectious cycle. Several in silico studies on natural derivatives, especially that present in daily refreshments (tea and fruit juices), staple food (black rice, red onions, soy beans etc) and traditional medicines (extracts of herbs, leaves and flowers) have been identified as potential drug candidates that bind efficiently with the key viral proteins. However, oral bioavailability of these nutriments is considerably low due to either poor permeability or loss of structure and function due to digestion in the gastrointestinal tract. Here we discuss few natural secondary metabolites (Delphinidin 3,5-diglucoside, Scutellarein 7-glucoside, Avicularin and 3,5-Di-O-galloylshikimic acid) that showed encouraging binding affinity against coronavirus main protease (Mpro) and human ACE2 receptor with MM-GBSA energies up to -74.0 Kcal/mol and -79.5 Kcal/mol, respectively. However, their Abbott bioavailability score (ABS) of 0.11 or 0.17 predicts poor oral bioavailability. This study could trigger interest to engineer potential natural products in managing present or future pandemics.Communicated by Ramaswamy H. Sarma.

Glycol chitosan in situ coating on PLGA nanoparticle curtails extraneous paclitaxel precipitates and imparts protein corona independent hemocompatibility.

Poly (lactide-co-glycolide) (PLGA) nanoparticles surface functionalized with water soluble glycol chitosan (GC) and carboxymethyl chitosan (CMC) has been studied for their drug (Paclitaxel and Doxorubicin) loading, yield, cellular uptake, serum protein adsorption and hemocompatibility. It was observed that Paclitaxel (Ptxl) phase out as Extraneous Ptxl Precipitates (EPP) (>25 %) in case of uncoated and CMC coated low molecular weight (LMW) PLGA nanoparticles (PNPs). The EPP formation was significantly reduced to ∼5 % with GC coating as it enhanced LMW PLGA precipitation and yield predominantly spherical polymeric nanoparticles towards better encapsulation of Ptxl and thus uniform intracellular drug distribution. Interestingly, protein corona analysis showed cmcPNPs and gcPNPs to be distinct from each other in associating mainly with serum proteins of molecular weight < 30 kDa and >30 kDa respectively. While CMC functionalization showed >10 % hemolysis, at similar concentration GC coating was found to provide superior hemocompatibility even in the absence of protein corona.

Dopamine functionalized CuO nanoparticles: A high valued "turn on" colorimetric biosensor for detecting cysteine in human serum and urine samples.

An attempt has been made to design one step synthesis of dopamine coated copper oxide nanoparticles (CuO@DOP NPs) by using microwave radiation method. The luminescent properties of CuO@DOP NPs have been explored for making colorimetric and visual biosensor for L-cys. Natural occurring dopamine has used as a precursor for the coating of CuO NPs that provides stability and generates functionality for the sensing of L-Cysteine (L-Cys). Being one of the important amino acid, L-cys has shown a fundamental role in living species due to the existence of sulfhydryl bonding which further affect the process of protein synthesis in living system. Therefore sensing of L-cys by using CuO@DOP NPs deserves higher consideration. Further, morphological and size parameters have been analyzed by using FESEM and HRTEM techniques. Surface interaction and coating of dopamine over CuO NPs has been examined through FTIR and TGA analysis. The non-toxicity and bio-compatibility of CuO@DOP NPs has been evaluated against L929 cell lines and on bacterial species. A computational study using DFT has been performed to check the possible mechanism of interaction between the CuO@DOP NPs and L-Cys. The higher value of detection limit (35 nM) has further shown its potential scope in sensing L-cys. The interference studies in presence of other amino acids have also taken into consideration for checking the selectivity and sensitivity of designed sensor. The applicability of prepared sensor has further been tested for real human blood serum and urine samples for detecting the presence of L-Cys. The as developed sensor of CuO@DOP NPs has provided rapid and selective sensing ability towards L-Cys over a wide range of concentration and bio-compatibility towards living entity. NOVELTY STATEMENT: Herein, the application of unique chemical and photo-luminescent properties of CuO NPs have been chosen for the fabrication of new type of fluorophore to complement conventional types of biosensor for L-Cys. The synthesis of CuO based biosensor has been achieved via an economically viable microwave assisted method. The article has not been published in any language anywhere and that it is not under simultaneous consideration by another journal. The current work is novel.

Nanomolar detection of biothiols via turn-ON fluorescent indicator displacement.

The thiol group is known to have a high affinity for gold nanoparticles and is capable of displacing other capping agents. We report a fluorescent indicator displacement technique for the detection of biothiols based on this principle. The displacement of BODIPY from the surface of gold nanoparticles served as a sensitive method for the detection of cysteine, homocysteine, and glutathione under a variety of conditions. It is noteworthy that the turn-ON fluorescence mechanism enabled the differentiation of normal cells from cancer cells because of the inherently higher concentrations of biothiols in the latter.

Polymeric Core-Shell Combinatorial Nanomedicine for Synergistic Anticancer Therapy.

Core-shell nanostructures are promising platforms for combination drug delivery. However, their complicated synthesis process, poor stability, surface engineering, and low biocompatibility are major hurdles. Herein, a carboxymethyl chitosan-coated poly(lactide-co-glycolide) (cmcPLGA) core-shell nanostructure is prepared via a simple one-step nanoprecipitation self-assembly process. Engineered core-shell nanostructures are tested for combination delivery of loaded docetaxel and doxorubicin in a cancer-mimicked environment. The drugs are compartmentalized in a shell (doxorubicin, Dox) and a core (docetaxel, Dtxl) with loading contents of ∼1.2 and ∼2.06%, respectively. Carboxymethyl chitosan with both amine and carboxyl groups act as a polyampholyte in diminishing ζ-potential of nanoparticles from fairly negative (-13 mV) to near neutral (-2 mV) while moving from a physiological pH (7.4) to an acidic tumor pH (6) that can help the nanoparticles to accumulate and release the drug on-site. The dual-drug formulation was found to carry a clinically comparable 1.7:1 weight ratio of Dtxl/Dox, nanoengineered for the sequential release of Dox followed by Dtxl. Single and engineered combinatorial nanoformulations show better growth inhibition toward three different cancer cells compared to free drug treatment. Importantly, Dox-Dtxl cmcPLGA nanoparticles scored synergism with combination index values between 0.2 and 0.3 in BT549 (breast ductal carcinoma), PC3 (prostate cancer), and A549 (lung adenocarcinoma) cell lines, demonstrating significant cell growth inhibition at lower drug concentrations as compared to single-drug control groups. The observed promising performance of dual-drug formulation is due to the G2/M phase arrest and apoptosis.

A three-component supramolecular nanocomposite as a heavy-atom-free photosensitizer.

Design of photosensitizers capable of generating singlet oxygen is crucial for the success of photodynamic therapy, and biocompatible supramolecular systems are emerging in this area. We report a supramolecular nanocomposite consisting of BODIPY, tryptophan and gold nanoparticles. While the individual components in isolation were inactive, the nanocomposite was found to be photostable and exhibited efficient photosensitization properties.

Magnetic and Photocatalytic Curcumin Bound Carbon Nitride Nanohybrids for Enhanced Glioma Cell Death.

A mesoporous magnetic nanohybrid functionalized with 14 wt % carbon nitride (CN) and loaded with curcumin (Cur) has been developed as a combination platform for photodynamic therapy and magnetic hyperthermia. CN-Cur complexes on the nanoparticle surface facilitate fast charge separation of hole-electron pairs under blue LED light irradiation and subsequent singlet oxygen generation. Cur release from the nanoparticle was significant only when exposed to both lysosomal pH (pH = 5.2) and an alternating current magnetic field (AMF). The mesoporous magnetic carbon nitride (MMCN) caused a 350% increase in the level of intracellular ROS as compared to the light exposed untreated control group. The nanohybrid was non-hemolytic and found to be biocompatible with HUVEC cells at concentrations up to 360 µg/mL. A similar concentration under AMF exposure caused a localized temperature rise of 4.2 °C and resulted in a 60% reduction in C6 cell viability. The cancer cell death further increased up to 80% under sequential exposure to light and AMF. The combinatorial treatment exerted significant cytoskeletal and nuclear damage in the cancer cells as assessed by confocal microscopy. The nanohybrid also exhibited relaxivity of 88 mM-1 s-1, imparting significant T2 weighted contrast to the cancer cells.