Innovative nano-carriers in anticancer drug delivery-a comprehensive review

Nanobiotechnology-assisted therapies to manage brain cancer in personalized manner

There are numerous investigated factors that limit brain cancer treatment efficacy such as ability of prescribed therapy to cross the blood-brain barrier (BBB), tumor specific delivery of a therapeutics, transport within brain interstitium, and resistance of tumor cells against therapies. Recent breakthroughs in the field of nano-biotechnology associated with developing multifunctional nano-theranostic emerged as an effective way to manage brain cancer in terms of higher efficacy and least possible adverse effects. Keeping challenges and state-of-art accomplishments into consideration, this review proposes a comprehensive, careful, and critical discussion focused on efficient nano-enabled platforms including nanocarriers for drug delivery across the BBB and nano-assisted therapies (e.g., nano-immunotherapy, nano-stem cell therapy, and nano-gene therapy) investigated for brain cancer treatment. Besides therapeutic efficacy point-of-view, efforts are being made to explore ways projected to tune such developed nano-therapeutic for treating patients in personalized manner via controlling size, drug loading, delivery, and retention. Personalized brain tumor management based on advanced nano-therapies can potentially lead to excellent therapeutic benefits based on unique genetic signatures in patients and their individual disease profile. Moreover, applicability of nano-systems as stimulants to manage the brain cancer growth factors has also been discussed in photodynamic therapy and radiotherapy. Overall, this review offers a comprehensive information on emerging opportunities in nanotechnology for advancing the brain cancer treatment.

Real-time transport kinetics of drug encapsulated nanoparticles into apoptotic cancer cells inside microchannels

Development of nanocomposites as drug delivery vectors is a burgeoning field of research. However, the usage of such newly invented nanomatrices are often limited by the shortcomings associated with the testing of their real-life efficacy. Many drugs fail because a monolayer framework ofin vitrocell line screening method does not adequately mimic thein vivothree-dimensional microenvironments. In this direction, the study unveils the development of a continuous flow microreactor wherein the cellulose acetate nanoparticles (CANPs) with varying sizes are prepared before encapsulating them with an anticancer drug-doxorubicin (DOX). Subsequently, anin vitromicrofluidic drug delivery model has been introduced in which the HeLa cells specific to cervical cancer is treated with the DOX encapsulated CANPs-DOX@CANPs. Thereafter, the transport of the drugs from the fluidic to cellular environment, their transport inside the cell, and the real-time kinetics of the cancer cell apoptosis have been analyzed systematically to uncover the real-time efficacy and cytotoxic effects of the nanocomposite. Interestingly, experiments reveal, (i) ∼89.4% DOX loading on the nanocomposite owing to a facile electrostatic interaction, (ii) a pH-dependent controlled release of drug during the transport with the cancer cells, and (iii) cell apoptosis after the diffused inoculation of the drug. A mathematical model has been developed to emulate the drug transport from the surrounding fluid to the cancer cells. Experiments together with the mathematical model uncover that the kinetics of cancer cell death is limited by the reaction at the cell-nucleus. The microfluidic model has shown significant potential to be translated as a useful tool for the real-time and on-demandin vitroscreening of the cancer drugs.

Nanoencapsulation of Hirudo medicinalis proteins in liposomes as a nanocarrier for inhibiting angiogenesis through targeting VEGFA in the Breast cancer cell line (MCF-7)

Introduction: Breast cancer is the most serious cause of women’s death throughout the world. Using nanocarrier vehicles to the exact site of cancer upgrades the therapeutic efficiency of the drugs. Capsulation of active proteins in the vesicular liposomes’ hydrophilic core is essential to develop a therapeutic protein carrier system. We aimed to encapsulate the medicinal leech saliva extract (LSE) and assess the inhibition of angiogenesis of breast cancer cells by targeting vascular endothelial growth factor A (VEGFA). Methods: In this research, enhanced formulation of liposomal protein was determined by zeta potential analysis, droplet size, drug release assay, and transmission electron microscopy (TEM). Furthermore, a cytotoxicity assay of liposomal LSE was performed to determine the cytotoxic activity of components. For assessing the expression of VEGFA, P53, and hypoxia-inducible factor subunit alpha (HIF1a) genes, Real-Time PCR was applied. Results: Nano liposome was chosen as an enhanced formulation due to its much smaller size (46.23 nm). Liposomal LSE had more practical actions on the MCF-7 cells. As noticed by DAPI staining, apoptosis was extensively greater in treated MCF-7 cells. Wound healing assay demonstrated that MCF-7 cells could not sustain growth at the presence of liposomal LSE and expression of the VEGFA gene was declined in treated cells. Downregulation of VEGFA was evaluated with western blotting technique. Conclusion: It can be concluded that our investigation of the tests confirmed the fact that nano liposomal LSE is a novel promising formulation for anticancer drugs and can significantly improve the penetration of protein drugs to cancer cells.

Synthesis and anticancer evaluation of some coumarin and azacoumarin derivatives

Coumarin and its nitrogen analogue 1-aza coumarin are a class of lactones and lactams, respectively, which are indispensable heterocyclic units to both chemists and biochemists. 1-Aza coumarin derivatives, which ultimately metabolize as the corresponding 8-hydroxy coumarins in the biological system are therefore found to be very good anti-inflammatory, anti-cancer, and analgesic agents. A series of hybrid substituted coumarin and azacoumarin-3-carboxylic acid derivatives (8-methoxycoumarin-3-carboxylic acid (4a), 8-methoxyazacoumarin-3-carboxylic acid (4b), 5-bromo-8-methoxycoumarin-3-carboxylic acid (5a), 5-bromo-8-methoxyazacoumarin-3-carboxylic acid (5b), 2-acetoxy-5-bromo-8-methoxyquinoline-3-carboxylic acid (6), and 5,7-di(phenylazo)-8-methoxycoumarin-3-carboxylic acid (7) were synthesized and structurally proved using spectral and elemental analysis data. Substituted coumarin-3-carboxylic acid (4a and 5a) and Substituted azacoumarin-3-carboxylic acid (4b, 5b and 6) were tested for their in vitro cytotoxic activity against MCF-7 and HepG-2 cell lines.

Potentialities of bioinspired metal and metal oxide nanoparticles in biomedical sciences

To date, various reports have shown that metallic gold bhasma at the nanoscale form was used as medicine as early as 2500 B.C. in India, China, and Egypt. Owing to their unique physicochemical, biological, and electronic properties, they have broad utilities in energy, environment, agriculture and more recently, the biomedical field. The biomedical domain has been used in drug delivery, imaging, diagnostics, therapeutics, and biosensing applications. In this review, we will discuss and highlight the increasing control over metal and metal oxide nanoparticle structures as smart nanomaterials utilized in the biomedical domain to advance the role of biosynthesized nanoparticles for improving human health through wide applications in the targeted drug delivery, controlled release drug delivery, wound dressing, tissue scaffolding, and medical implants. In addition, we have discussed concerns related to the role of these types of nanoparticles as an anti-viral agent by majorly highlighting the ways to combat the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) pandemic, along with their prospects.

DNA Based and Stimuli-Responsive Smart Nanocarrier for Diagnosis and Treatment of Cancer: Applications and Challenges

The rapid development of multidrug co-delivery and nano-medicines has made spontaneous progress in tumor treatment and diagnosis. DNA is a unique biological molecule that can be tailored and molded into various nanostructures. The addition of ligands or stimuli-responsive elements enables DNA nanostructures to mediate highly targeted drug delivery to the cancer cells. Smart DNA nanostructures, owing to their various shapes, sizes, geometry, sequences, and characteristics, have various modes of cellular internalization and final disposition. On the other hand, functionalized DNA nanocarriers have specific receptor-mediated uptake, and most of these ligand anchored nanostructures able to escape lysosomal degradation. DNA-based and stimuli responsive nano-carrier systems are the latest advancement in cancer targeting. The data exploration from various studies demonstrated that the DNA nanostructure and stimuli responsive drug delivery systems are perfect tools to overcome the problems existing in the cancer treatment including toxicity and compromised drug efficacy. In this light, the review summarized the insights about various types of DNA nanostructures and stimuli responsive nanocarrier systems applications for diagnosis and treatment of cancer.

Emerging Significance and Therapeutic Potential of Extracellular vesicles

Extracellular vesicles (EVs), are membrane-bound vesicles that have many advantages over traditional nanocarriers for drug and gene delivery. Evidence from recent studies indicate that EVs have therapeutic capability with chemical or biological modification. Tumor-derived exosomes (TEXs) were used as a new type of antigens or tumor vaccines in anti-tumor immunotherapy. With superior characteristics, modified EVs were applied to loaded and delivered synthetic drugs, silencing RNA, and microRNA for treatment. Different surface functionalization strategies have been proposed to improve the therapeutic functions of EVs. Appropriately modified EVs for disease intervention provide new avenues for effective clinical treatment strategies. Therefore, this review aimed at elucidating the therapeutic functions of EVs to generate new ideas for treatment and to unlock their hidden potential in translational medicine.

A 2-(benzothiazol-2-yl)-phenolato platinum(II) complex as potential photosensitizer for combating bacterial infections in lung cancer chemotherapy†

Cancer and antibiotic resistance are two global health threats that usually hamper clinical chemotherapeutic efficacy. Particularly for lung cancer, bacterial infections frequently arise thereby complicating the course of cancer treatment. In this sense, three new neutral luminescent cycloplatinated(II) photosensitizers of the type [Pt(dmba)(L)] (dmba = N,N-dimethylbenzylamine-κN,κC; L = 2-(benzo[d]oxazol-2-yl)-phenolato-κN,κO1, 2-(benzo[d]thiazol-2-yl)-phenolato-κN,κO2, and 2-(1-methyl-1H-benzo[d]imidazole-2-yl)phenolato-κN,κO3) have been characterized and developed to potentially eliminate both resistant bacteria and lung cancer cells. The phototherapeutic effects of complex 2 have been evaluated using low doses of blue light irradiation. Complex 2 exerted promising photoactivity against pathogenic Gram-positive bacteria strains of clinical interest, displaying a phototoxic index (PI) of 15 for methicillin-resistant Staphylococcus aureus, one of the major microorganisms predominating lung infections. Likewise, the anticancer activity of 2 was also increased upon light irradiation in human lung A549 cancer cells (PI = 36). Further in vitro experiments with this platinum(II) complex suggest that ROS-generating photodynamic reactions were involved upon light irradiation, thus providing a reasonable mechanism for its dual anticancer and antibacterial activities.

A magnified aptamer fluorescence sensor based on the metal organic frameworks adsorbed DNA with enzyme catalysis amplification for ultra-sensitive determination of ATP and its logic gate operation

With the development of frame materials, metal organic frameworks (MOFs) have been successfully applied in the fields of biological small molecule analysis and fluorescent DNA detection. In this work, in view of the good adsorption characteristics of MIL-101(Cr), the highly sensitive detection of adenosine triphosphate (ATP) assisted nucleic acid exonuclease amplification by MIL-101(Cr) on the different affinity of single stranded DNA and double stranded DNA was investigated. The detection limit of ATP reaches 1.7 μM, and the platform has good applicability in biological samples. On this basis, an "AND" logic gate was successfully constructed. Superior sensitivity to ATP in the presence of exonuclease was reflected, which greatly enhanced the system's fluorescence. Importantly, the fluorescence sensing application of this nanomaterial inspired other target detection and enriched the building blocks of fluorescence sensing platform.

Isoxazole derivatives as anticancer agent: A review on synthetic strategies, mechanism of action and SAR studies

Breast cancer is the second most leading cause of death among women. Multiple drugs have been approved by FDA for the treatment of BC. The major drawbacks of existing drugs are the development of resistance, toxicity, selectivity problem. The other therapies like hormonal therapy, surgery, radiotherapy, and immune therapy are in use but showed many side effects like bioavailability issues, non-selectivity, pharmacokinetic-pharmacodynamic problems. Therefore, there is an urgent need to develop new moieties that are nonviolent and more effective in the treatment of cancer. Isoxazole derivatives have gain popularity in recent years due to anticancer potential with the least side effects. These derivatives act as an anticancer agent with different mechanisms like inducing apoptosis, aromatase inhibition, disturbing tubulin congregation, topoisomerase inhibition, HDAC inhibition, and ERα inhibition. In this article, we have explored the synthetic strategies, anticancer mechanism of action along with SAR studies of isoxazole derivatives.

Towards Universal Stimuli-Responsive Drug Delivery Systems: Pillar[5]arenes Synthesis and Self-Assembly into Nanocontainers with Tetrazole Polymers

In this work, we have proposed a novel universal stimulus-sensitive nanosized polymer system based on decasubstituted macrocyclic structures-pillar[5]arenes and tetrazole-containing polymers. Decasubstituted pillar[5]arenes containing a large, good leaving tosylate, and phthalimide groups were first synthesized and characterized. Pillar[5]arenes containing primary and tertiary amino groups, capable of interacting with tetrazole-containing polymers, were obtained with high yield by removing the tosylate and phthalimide protection. According to the fluorescence spectroscopy data, a dramatic fluorescence enhancement in the pillar[5]arene/fluorescein/polymer system was observed with decreasing pH from neutral (pH = 7) to acidic (pH = 5). This indicates the destruction of associates and the release of the dye at a pH close to 5. The presented results open a broad range of opportunities for the development of new universal stimulus-sensitive drug delivery systems containing macrocycles and nontoxic tetrazole-based polymers.

Strategic targeting of non-small-cell lung cancer utilizing genetic material-based delivery platforms of nanotechnology

Several limitations of conventional cancer treatment such as non-specific targeting, solubility problems, and ineffective entry of chemotherapeutics into cancer cells can be overcome by using nanotechnology targeted drug delivery systems. Some combinations of biomolecules and nanoparticles have proven to be excellent therapeutics for Non-small cell lung cancer (NSCLC) in the last decades. Targeted gene delivery has shown in vivo as well as in vitro promising results with therapeutic efficacy. Gene therapy has shown enhanced transfection efficiency and better targeting potential on several NSCLC cell lines. Still, there are several challenges in nanoparticle-mediated gene therapy, which include stability of biomolecules and nanoparticles during delivery, managing their biodistribution, and reducing the possible cytotoxic effects of the nanoparticles, which need to be solved before clinical trials. Evaluation of therapeutic efficacy of biomolecules and nanoparticle combination in gene therapy must be established to expand the application of nano-gene therapy in cancer treatment.

Surface engineered iron oxide nanoparticles as efficient materials for antibiofilm application

Overuse of antibiotics has led to the development of multi drug resistant strains. Antibiotic resistance is a major drawback in the biomedical field since medical implants are prone to infection by biofilms of antibiotic resistant strains of bacteria. With increasing prevalence of antibiotic resistant pathogenic bacteria, the search for alternative method is utmost importance. In this regard, magnetic nanoparticles are commonly used as a substitute for antibiotics that can circumvent the problem of biofilms growth on the surface of biomedical implants. Iron oxide nanoparticles (IONPs) have unique magnetic properties that can be exploited in various ways in the biomedical applications. IONPs are engineered employing different methods to induce surface functionalization that include the use of polyethyleneimine and oleic acid. IONPs have a mechanical effect on biofilms when in presence of an external magnet. In this review, a detailed description of surface engineered magnetic nanoparticles as ideal antibacterial agents is provided, accompanied by various methods of literature review. This article is protected by copyright. All rights reserved.

A research update on the therapeutic potential of rhein and its derivatives

Rhein is one of the anthraquinones components of Rheum. It shows excellent clinical efficacy and is widely used in the management of several disease conditions including tumors, inflammation, diabetic nephropathy, and viral infections. In this review, we summarize the recent studies on the pharmacological activities of rhein and its derivatives, as well as their association with different diseases and possible mechanisms based on our previous review. This review serves as an updated and a supplement to our previous report highlighting the use of rhein in nanotechnology. It also serves as a reference study and offers an overall picture of the use of rhein and its derivatives in nanotechnology.

Stimuli-Responsive, Plasmonic Nanogel for Dual Delivery of Curcumin and Photothermal Therapy for Cancer Treatment

Nanogels (Ng) are crosslinked polymer-based hydrogel nanoparticles considered to be next-generation drug delivery systems due to their superior properties, including high drug loading capacity, low toxicity, and stimuli responsiveness. In this study, dually thermo-pH-responsive plasmonic nanogel (AuNP@Ng) was synthesized by grafting poly (N-isopropyl acrylamide) (PNIPAM) to chitosan (CS) in the presence of a chemical crosslinker to serve as a drug carrier system. The nanogel was further incorporated with gold nanoparticles (AuNP) to provide simultaneous drug delivery and photothermal therapy (PTT). Curcumin's (Cur) low water solubility and low bioavailability are the biggest obstacles to effective use of curcumin for anticancer therapy, and these obstacles can be overcome by utilizing an efficient delivery system. Therefore, curcumin was chosen as a model drug to be loaded into the nanogel for enhancing the anticancer efficiency, and further, its therapeutic efficiency was enhanced by PTT of the formulated AuNP@Ng. Thorough characterization of Ng based on CS and PNIPAM was conducted to confirm successful synthesis. Furthermore, photothermal properties and swelling ratio of fabricated nanoparticles were evaluated. Morphology and size measurements of nanogel were determined by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Nanogel was found to have a hydrodynamic size of ~167 nm and exhibited sustained release of curcumin up to 72 h with dual thermo-pH responsive drug release behavior, as examined under different temperature and pH conditions. Cytocompatibility of plasmonic nanogel was evaluated on MDA-MB-231 human breast cancer and non-tumorigenic MCF 10A cell lines, and the findings indicated the nanogel formulation to be cytocompatible. Nanoparticle uptake studies showed high internalization of nanoparticles in cancer cells when compared with non-tumorigenic cells and confocal microscopy further demonstrated that AuNP@Ng were internalized into the MDA-MB-231 cancer cells via endosomal route. In vitro cytotoxicity studies revealed dose-dependent and time-dependent drug delivery of curcumin loaded AuNP@Ng/Cur. Furthermore, the developed nanoparticles showed an improved chemotherapy efficacy when irradiated with near-infrared (NIR) laser (808 nm) in vitro. This work revealed that synthesized plasmonic nanogel loaded with curcumin (AuNP@Ng/Cur) can act as stimuli-responsive nanocarriers, having potential for dual therapy i.e., delivery of hydrophobic drug and photothermal therapy.

Curcumin Encapsulated Casein Nanoparticles: Enhanced Bioavailability and Anticancer Efficacy

The poor water solubility and bioactivity of drugs can be potentially improved by using suitable nanocarriers. Herein, an economically viable methodology is developed for encapsulation of hydrophobic anticancer agent, curcumin in casein nanoparticles (CasNPs). The successful encapsulation of curcumin was evident from the structural, thermal and spectroscopic analysis of curcumin encapsulated CasNPs (Cur-CasNPs). The CasNPs and Cur-CasNPs samples were lyophilized for their long-term stability and lyophilized powders are found to be stable for more than 6 months at 4-8 °C. From DLS studies, it has been observed that the variation in average size of drug formulations before and after reconstitution were less than 5%. Further, it shows good water-dispersibility, enhanced bioavailability and pH dependent charge conversal feature. Cur-CasNPs showed pH dependent release characteristics with higher at mild acidic environment and enhanced toxicity towards cancer cells (MCF-7) as compared to normal cells (CHO). Moreover, the CasNPs are non-toxic in nature and the developed nanoformulation of drug exhibits substantial cellular internalization and enhanced toxicity towards MCF-7 cells over pure drug, indicating their potential applications.

Nanomedicine-Combined Immunotherapy for Cancer

BACKGROUND

Immunotherapy for cancer includes Chimeric Antigen Receptor (CAR)-T cells, CAR-natural Killer (NK) cells, PD1, and the PD-L1 inhibitor. However, the proportion of patients who respond to cancer immunotherapy is not satisfactory. Concurrently, nanotechnology has experienced a revolution in cancer diagnosis and therapy. There are few clinically approved nanoparticles that can selectively bind and target cancer cells and incorporate molecules, although many therapeutic nanocarriers have been approved for clinical use. There are no systematic reviews outlining how nanomedicine and immunotherapy are used in combination to treat cancer.

OBJECTIVE

This review aims to illustrate how nanomedicine and immunotherapy can be used for cancer treatment to overcome the limitations of the low proportion of patients who respond to cancer immunotherapy and the rarity of nanomaterials in clinical use.

METHODS

A literature review of MEDLINE, PubMed / PubMed Central, and Google Scholar was performed. We performed a structured search of literature reviews on nanoparticle drug-delivery systems, which included photodynamic therapy, photothermal therapy, photoacoustic therapy, and immunotherapy for cancer. Moreover, we detailed the advantages and disadvantages of the various nanoparticles incorporated with molecules to discuss the challenges and solutions associated with cancer treatment.

CONCLUSION

This review identified the advantages and disadvantages associated with improving health care and outcomes. The findings of this review confirmed the importance of nanomedicinecombined immunotherapy for improving the efficacy of cancer treatment. It may become a new way to develop novel cancer therapeutics using nanomaterials to achieve synergistic anticancer immunity.

Remotely Activated Nanoparticles for Anticancer Therapy

Cancer has nowadays become one of the leading causes of death worldwide. Conventional anticancer approaches are associated with different limitations. Therefore, innovative methodologies are being investigated, and several researchers propose the use of remotely activated nanoparticles to trigger cancer cell death. The idea is to conjugate two different components, i.e., an external physical input and nanoparticles. Both are given in a harmless dose that once combined together act synergistically to therapeutically treat the cell or tissue of interest, thus also limiting the negative outcomes for the surrounding tissues. Tuning both the properties of the nanomaterial and the involved triggering stimulus, it is possible furthermore to achieve not only a therapeutic effect, but also a powerful platform for imaging at the same time, obtaining a nano-theranostic application. In the present review, we highlight the role of nanoparticles as therapeutic or theranostic tools, thus excluding the cases where a molecular drug is activated. We thus present many examples where the highly cytotoxic power only derives from the active interaction between different physical inputs and nanoparticles. We perform a special focus on mechanical waves responding nanoparticles, in which remotely activated nanoparticles directly become therapeutic agents without the need of the administration of chemotherapeutics or sonosensitizing drugs.

Hydrothermal method-based synthesized tin oxide nanoparticles: Albumin binding and antiproliferative activity against K562 cells

The interaction of nanoparticles with protein and cells may provide important information regarding their biomedical implementations. Herein, after synthesis of tin oxide (SnO₂) nanoparticles by hydrothermal method, their interaction with human serum albumin (HSA) was evaluated by multispectroscopic and molecular docking (MD) approaches. Furthermore, the selective antiproliferative impact of SnO₂ nanoparticles against leukemia K562 cells was assessed by different cellular assays, whereas lymphocytes were used as control cells. TEM, DLS, zeta potential and XRD techniques showed that crystalline SnO₂ nanoparticles have a size of less than 50 nm with a good colloidal stability. Fluorescence and CD spectroscopy analysis indicated that the HSA undergoes some slight conformational changes after interaction with SnO₂ nanoparticles, whereas the secondary structure of HSA remains intact. Moreover, MD outcomes revealed that the charged residues of HSA preferentially bind to SnO₂ nanoclusters in the binding pocket. Antiproliferative examinations displayed that SnO₂ nanoparticles can selectively cause the mortality of K562 cells through induction of cell membrane leakage, activation of caspase-9, -8, -3, down regulation of Bcl-2 mRNA, the elevation of ROS level, S phase arrest, and apoptosis. In conclusion, this data may indicate that SnO₂ nanoparticles can be used as promising particles to be integrated into therapeutic platforms.

Azo-inserted responsive hybrid liposomes for hypoxia-specific drug delivery

Stimuli-responsive drug delivery systems using endogenous stimuli from tumor microenvironments such as acidic pH, over-expressed enzyme, and high redox potential as triggers have shown tremendous promise in cancer therapy. However, their clinical application is severely limited because of tumor heterogeneity. Hypoxia, a physiological feature observed in almost all solid tumors and even in nodules with very small size, has currently emerged as a more general but efficient stimulus to trigger release. Herein, we developed hypoxia-responsive hybrid liposomes (HR-HLPs), composed of azo-inserted organokoxysilane-based lipid analogue as a responsive component and commercial phospholipid for reducing the rigidity of liposomal membrane caused by azo, for drug delivery targeting tumor hypoxia. HR-HLPs had the advantages of high structural stability to avoid premature drug leakage when circulating in the blood and high sensitivity in responding to hypoxia once reaching tumor sites. HR-HLPs exhibit deep tumor penetration capability, enabling effective delivery to hypoxic regions distant from tumor vessels. Moreover, HR-HLPs could selectively release their payload, co-localizing with over-expressed hypoxia inducible factor 1α (HIF-1α) in vitro and in vivo. As a result, HR-HLPs showed improved therapeutic outcome accompanied by reduced adverse effects. The results highlighted the potential application of azo-inserted responsive hybrid liposomes for hypoxia-targeted drug delivery. STATEMENT OF SIGNIFICANCE.

Macrophage membrane coated persistent luminescence nanoparticle@MOF-derived mesoporous carbon core-shell nanocomposites for autofluorescence-free imaging-guided chemotherapy

Efficient drug nanocarriers with high drug loading capacity and luminescent ability are in high demand for biomedical applications. Here we show a facile and bio-friendly synthesis of macrophage membrane coated persistent luminescence nanoparticle (PLNP)@metal-organic framework (MOF)-derived mesoporous carbon (MC) core-shell nanocomposites (PLMCs) for autofluorescence-free imaging-guided chemotherapy. MOF UiO-66 is used as both the precursor and the template, and is controllably coated on the surface of the PLNP to form a PLNP@UiO-66 core-shell composite. Subsequent calcination enables the transformation of PLNP@UiO-66 to PLMC due to the pyrolysis of the UiO-66 shell. PLMC with a small particle size of 70 nm, a tunable large pore size from ∼4.8 to ∼16.2 nm in the shell and near-infrared persistent luminescence in the core was prepared by controlling the calcination conditions. The prepared PLMC showed an enhanced drug loading capacity for three model drugs (doxycycline hydrochloride, acetylsalicylic acid, and paclitaxel) compared with PLNP@UiO-66. Further coating of the macrophage membrane on the surface of PLMC results in MPLMC with enhanced cloaking ability for evading the mononuclear phagocyte system. The drug-loaded MPLMC is promising for autofluorescence-free persistent luminescence imaging-guided drug delivery and tumor therapy.

Cerium Oxide Nanoparticles: Recent Advances in Tissue Engineering

Submicron biomaterials have recently been found with a wide range of applications for biomedical purposes, mostly due to a considerable decrement in size and an increment in surface area. There have been several attempts to use innovative nanoscale biomaterials for tissue repair and tissue regeneration. One of the most significant metal oxide nanoparticles (NPs), with numerous potential uses in future medicine, is engineered cerium oxide (CeO2) nanoparticles (CeONPs), also known as nanoceria. Although many advancements have been reported so far, nanotoxicological studies suggest that the nanomaterial's characteristics lie behind its potential toxicity. Particularly, physicochemical properties can explain the positive and negative interactions between CeONPs and biosystems at molecular levels. This review represents recent advances of CeONPs in biomedical engineering, with a special focus on tissue engineering and regenerative medicine. In addition, a summary report of the toxicity evidence on CeONPs with a view toward their biomedical applications and physicochemical properties is presented. Considering the critical role of nanoengineering in the manipulation and optimization of CeONPs, it is expected that this class of nanoengineered biomaterials plays a promising role in the future of tissue engineering and regenerative medicine.

Plasmon-Enhanced Controlled Drug Release from Ag-PMA Capsules

Silver (Ag)-grafted PMA (poly-methacrylic acid, sodium salt) nanocomposite loaded with sorafenib tosylate (SFT), an anticancer drug, showed good capability as a drug carrier allowing on-demand control of the dose, timing and duration of the drug release by laser irradiation stimuli. In this study, the preparation of Ag-PMA capsules loaded with SFT by using sacrificial silica microparticles as templates was reported. A high drug loading (DL%) of ∼13% and encapsulation efficiency (EE%) of about 76% were obtained. The photo-release profiles were regulated via the adjustment of light wavelength and power intensity. A significant improvement of SFT release (14% vs. 21%) by comparing SFT-Ag-PMA capsules with Ag-PMA colloids under the same experimental conditions was observed. Moreover, an increase of drug release by up to 35% was reached by tuning the laser irradiation wavelength near to Ag nanoparticles’ surface plasmon resonance (SPR). These experimental results together with more economical use of the active component suggest the potentiality of SFT-Ag-PMA capsules as a smart drug delivery system.

Exploring the direct synthesis of exchange-spring nanocomposites by reduction of CoFe2O4 spinel nanoparticles using in situ neutron diffraction

In situ neutron powder diffraction (NPD) was employed for investigating gram-scale reduction of hard magnetic CoFe2O4 (spinel) nanoparticles into CoFe2O4/CoFe2 exchange-spring nanocomposites via H2 partial reduction. Time-resolved structural information was extracted from Rietveld refinements of the NPD data, revealing significant changes in the reduction kinetics based on the applied temperature and H2 available. The nanocomposite formation was found to take place via the following two-step reduction process: CoxFe3-xO4 → CoyFe1-yO → CozFe2-z. The refined lattice parameters and site occupation fractions indicate that the reduced phases, i.e. CoyFe1-yO and CozFe2-z, initially form as Co-rich compounds (i.e. y > 0.33 and z > 1), which gradually incorporate more Fe as the reduction proceeds. The reduction depletes the Co-content in the parent spinel, which may end up becoming magnetically soft Fe3O4 at high temperature (T = 542 °C), while at lower temperatures there may be a co-existence of Fe3O4 and γ-Fe2O3 or CoxFe3-xO4. The macroscopic magnetic properties of the products were measured by vibrating sample magnetometry (VSM) and revealed the hard and soft magnetic domains in the nanocomposites to be effectively exchange-coupled. An increase of approximately 70% in specific saturation magnetisation, remanence magnetisation, and coercivity compared to the parent CoFe2O4 material was achieved for the best sample.

Preparation, radiolabeling with 99mTc and 67Ga and biodistribution studies of albumin nanoparticles covered with polymers

OBJECTIVE

To optimize radiolabeling with ^99mTc and ⁶⁷Ga of albumin nanoparticles coated with 4 differents synthetic polymers and to evaluate their stability in vivo and in vitro, as well as their biodistribution in vivo after intravenous administration.

MATERIAL AND METHODS

The nanoparticles were prepared using albumin and NOTA-modified albumin by the desolvation method and coated with 4 different polymers; HPMC, GMN2, GPM2 and GTM2. They were purified, lyophilized and characterized. Radiolabelling with ^99mTc was perfomed with 74 MBq of ^99mTc sodium pertechnetate, previously reduced with and acid solution of tin chloride at different concentrations (0.003, 0.005, 0.007, 0.01, 0.05 and 0.1mg/ml) and at different times (5, 10, 15, 30 and 60minutes) and temperatures (room temperature, 40°C and 60°C). Radiolabelling with ⁶⁷Ga was perfomed by incubation of the nanoparticles with 37 MBq of ⁶⁷Gallium chloride (obtained from commercial gallium-⁶⁷ citrate) at different times (10 and 30minutes) and temperatures (room temperature, 30°C and 60°C), and posterior purification with microconcentrators. The radiochemical purity was evaluated by TLC. Stability studies of radiolabeled nanoparticles in physiological serum and blood plasma were perfomed. Biodistribution studies of nanoparticles coated with GPM2 polymer were carried out in Wistar rats after intravenous administration of the nanoparticles. Control animals were carried out with ^99mTc sodium pertechnetate and ⁶⁷Ga chloride. To do so, the animals were killed and activity in organs was measured in a gamma counter.

RESULTS

^99mTc labeling was carried out optimally with a tin concentration of 0.007mg/ ml for the GPM2 nanoparticles and 0.005mg / ml for the rest of the formulations, with a radiolabelling time of 10minutes at room temperature. In the case of ⁶⁷Ga the label was optimized at 30° C temperature and 30minutes of incubation. In both cases the radiochemical purity obtained was greater than 97%. The nanoparticles showed high stability in vitro after 48hours of labeling (70% nanoparticles labeled with ^99mTc and 90% those labeled with ⁶⁷Ga). Biodistribution studies of nanoparticles ^99mTc -GPM2 and ⁶⁷Ga -NOTA-GPM2 showed a high accumulation of activity in the liver at 2 and 24hours after intravenous administration.

CONCLUSION

The labeling procedure with ^99mTc and ⁶⁷Ga of albumin and albumin modified with NOTA nanoparticles allows obtaining nanoparticles with high labeling yields and adequate in vitro stability, allowing their use for in vivo studies.

Coating and Functionalization Strategies for Nanogels and Nanoparticles for Selective Drug Delivery

Drug delivery is a fascinating research field with several development opportunities. Great attention is now focused on colloidal systems, nanoparticles, and nanogels and on the possibility of modifying them in order to obtain precise targeted drug delivery systems. The aim of this review is to give an overview of the main available surface functionalization and coating strategies that can be adopted in order to modify the selectivity of the nanoparticles in the delivery process and obtain a final system with great targeted drug delivery ability. We also highlight the most important fields of application of these kinds of delivery systems and we propose a comparison between the advantages and disadvantages of the described functionalization strategies.

Mastering bioactive coatings of metal oxide nanoparticles and surfaces through phosphonate dendrons

Dendritic phosphonates are versatile coatings of several nanomaterials for health applications ranging from implants to nanoparticles and microbubbles.

Green synthesis and biological evaluation of novel 5-fluorouracil derivatives as potent anticancer agents

This study reports the formation of 5-FU co-crystals with four different pharmacologically safe co-formers; Urea, Thiourea, Acetanilide and Aspirin using methanol as a solvent. Two fabrication schemes were followed i.e., solid-state grinding protocol, in which API and co-formers were mixed through vigorous grinding while in the other method separate solutions of both the components were made and mixed together. The adopted approaches offer easy fabrication protocols, no temperature maintenance requirements, no need of expensive solvents, hardly available apparatus, isolation and purification of the desired products. In addition, there is no byproducts formation, In fact, a phenomenon embracing the requirements of green synthesis. Through FTIR analysis; for API the N-H absorption frequency was recorded at 3409.02 cm-1 and that of -C[bond, double bond]O was observed at 1647.77 cm-1. These characteristics peaks of 5-FU were significantly shifted and recorded at 3499.40 cm-1 and 1649.62 cm-1 for 5-FU-Ac (3B) and 3496.39 cm-1 and 1659.30 cm-1 for 5-FU-As (4B) co-crystals for N-H and -C[bond, double bond]O groups respectively. The structural differences between API and co-crystals were further confirmed through PXRD analysis. The characteristic peak of 5-FU at 2θ = 28.79918o was significantly shifted in the graphs of co-crystals not only in position but also with respect to intensity and FWHM values. In addition, new peaks were also recorded in all the spectra of co-formers confirming the structural differences between API and co-formers. In addition, percent growth inhibition was also observed by all the co-crystals through MTT assay against HCT 116 colorectal cell lines in vitro. At four different concentrations; 25, 50, 100 and 200 µg/mL, slightly different trends of the effectiveness of API and co-crystals were observed. However; among all the co-crystal forms, 5-FU-thiourea co-crystals obtained through solution method (2B) proved to be the most effective growth inhibitor at all the four above mentioned concentrations.

Isatin-azole hybrids and their anticancer activities

Isatin and azole moieties, which have the ability to form various noncovalent interactions with different therapeutic targets, are common pharmacophores in drug development. Isatin and azole derivatives possess promising in vitro and in vivo anticancer activity, and many of them, such as semaxanib, sunitinib, and carboxyamidotriazole, could be used to treat various cancers. Thus, it is conceivable that hybridization of the isatin moiety with azole may provide a valuable therapeutic intervention for the treatment of cancer. Substantial efforts have been made to develop isatin-azole hybrids as novel anticancer agents, and some of the isatin-azole hybrids exhibited considerable activity. This review emphasizes isatin-azole hybrids with potential anticancer activity, covering articles published between 2010 and 2019. The structure-activity relationships as well as the mechanisms of action are also discussed to provide insights for the rational design of more effective candidates.

Molecularly Imprinted Polymers for Cell Recognition

Since their conception 50 years ago, molecularly imprinted polymers (MIPs) have seen extensive development both in terms of synthetic routes and applications. Cells are perhaps the most challenging target for molecular imprinting. Although early work was based almost entirely around microprinting methods, recent developments have shifted towards epitope imprinting to generate MIP nanoparticles (NPs). Simultaneously, the development of techniques such as solid phase MIP synthesis has solved many historic issues of MIP production. This review briefly describes various approaches used in cell imprinting with a focus on applications of the created materials in imaging, drug delivery, diagnostics, and tissue engineering.

Nanosystems as Vehicles for the Delivery of Antimicrobial Peptides (AMPs)

Recently, antimicrobial peptides (AMPs), also called host defence peptides (HDPs), are attracting great interest, as they are a highly viable alternative in the search of new approaches to the resistance presented by bacteria against antibiotics in infectious diseases. However, due to their nature, they present a series of disadvantages such as low bioavailability, easy degradability by proteases, or low solubility, among others, which limits their use as antimicrobial agents. For all these reasons, the use of vehicles for the delivery of AMPs, such as polymers, nanoparticles, micelles, carbon nanotubes, dendrimers, and other types of systems, allows the use of AMPs as a real alternative to treatment with antibiotics.

Rational approaches, design strategies, structure activity relationship and mechanistic insights for therapeutic coumarin hybrids

Hybrid molecules, furnished by combining two or more pharmacophores is an emerging concept in the field of medicinal chemistry and drug discovery that has attracted substantial traction in the past few years. Naturally occurring scaffolds such as coumarins display a wide spectrum of pharmacological activities including anticancer, antibiotic, antidiabetic and others, by acting on multiple targets. In this view, various coumarin-based hybrids possessing diverse medicinal attributes were synthesized in the last five years by conjugating coumarin moiety with other therapeutic pharmacophores. The current review summarizes the recent development (2014 and onwards) of these pharmacologically active coumarin hybrids and demonstrates rationale behind their design, structure-activity relationships (SAR) and mechanistic studies performed on these hybrid molecules. This review will be beneficial for medicinal chemist and chemical biologist, and in general to the drug discovery community and will facilitate the synthesis and development of novel, potent coumarin hybrid molecules serving as lead molecules for the treatment of complex disorders.

Molecular modelling of TLR agonist Pam3CSK4 entrapment in PLA nanoparticles as a tool to explain loading efficiency and functionality

Designing potent and safe-of-use therapies against cancers and infections remains challenging despite the emergence of novel molecule classes like checkpoint inhibitors or Toll-Like-Receptor ligands. The latest therapeutic perspectives under development for immune modulator administration exploits vectorization, and biodegradable delivery systems are one of the most promising vehicles. Nanoparticles based on Poly (D,L) Lactic Acid (PLA) as polymer for formulation are widely investigated due to its bioresorbable, biocompatible and low immunogen properties. We propose a PLA-based nanoparticle delivery system to vectorize Pam₃CSK₄, a lipopeptide TLR1/2 ligand and a potent activator of the proinflammatory transcription factor NF-κB that shows a self-assembling behavior from 30 µg/mL onwards. We demonstrate successful encapsulation of Pam₃CSK₄ in PLA nanoparticles by nanoprecipitation in a 40-180 µg/mL concentration range, with 99% of entrapment efficiency. By molecular modelling, we characterize drug/carrier interactions and conclude that Pam₃CSK₄ forms clusters onto the nanoparticle and is not encapsulated into the hydrophobic core. In silico predictions provide nanoprecipitation optimization and the mechanistic understanding of the particle dynamics. The loaded-Pam₃CSK₄ maintains bioactivity on TLR2, confirmed by in vitro experiments using reporter cell line HEK-Blue hTLR2. Our presented data and results are convincing evidence that Pam₃CSK₄-loaded in PLA nanoparticles represent a promising immune modulating system.

Verapamil delivery systems on the basis of mesoporous ZSM-5/KIT-6 and ZSM-5/SBA-15 polymer nanocomposites as a potential tool to overcome MDR in cancer cells

ZSM-5/KIT-6 and ZSM-5/SBA-15 nanoparticles were synthesized and further modified by a post-synthesis method with (CH₂)₃SO₃H and (CH₂)₃NHCO(CH₂)₂COOH groups to optimize their drug loading and release kinetic profiles. The verapamil cargo drug was loaded by incipient wetness impregnation both on the parent and modified nanoporous supports. Nanocarriers were then coated with a three-layer polymeric shell composed of chitosan-k-carrageenan-chitosan with grafted polysulfobetaine chains. The parent and drug loaded formulations were characterized by powder XRD, N₂ physisorption, thermal analysis, AFM, DLS, TEM, ATR-FT-IR and solid state NMR spectroscopies. Loading of verapamil on such nanoporous carriers and their subsequent polymer coating resulted in a prolonged in vitro release of the drug molecules. Quantum-chemical calculations were performed to investigate the strength of the interaction between the specific functional groups of the drug molecule and (CH₂)₃SO₃H and CH₂)₃NHCO(CH₂)₂COOH groups of the drug carrier. Furthermore, the ability of the developed nanocomposites to positively modulate the intracellular internalization and thereby augment the antitumor activity of the p-gp substrate drug doxorubicin was investigated in a comparative manner vs. free drug in a panel of MDR positive (HL-60/Dox, HT-29) and MDR negative (HL-60) human cancer cell lines using the Chou-Talalay method.