Nanocomposite liposomes containing quantum dots and anticancer drugs for bioimaging and therapeutic delivery: a comparison of cationic, PEGylated and deformable liposomes

Nano-inspired smart medicines targeting brain cancer: diagnosis and treatment

Cancer, despite being the bull's eye for the research community, accounts for a large number of morbidity and mortality. Cancer of the brain is considered the most intractable, with the least diagnosis rates, hence treatment and survival. Despite the extensive development of therapeutic molecules, their targeting to the diseased site is a challenge. Specially tailored nanoparticles can efficiently deliver drugs and genes to the brain to treat tumours and diseases. These nanotechnology-based strategies target the blood-brain barrier, the local space, or a specific cell type. These nanoparticles are preferred over other forms of targeted drug delivery due to the chances for controlled delivery of therapeutic cargo to the intended receptor. Targeted cancer therapy involves using specific receptor-blocking compounds that block the spreading or growth of cancerous cells. This review presents an account of the recent applications of nano-based cancer theragnostic, which deal in conjunct functionalities of nanoparticles for effective diagnosis and treatment of cancer. It commences with an introduction to tumours of the brain and their grades, followed by hurdles in its conventional diagnosis and treatment. The characteristic mechanism of nanoparticles for efficiently tracing brain tumour grade and delivery of therapeutic genes or drugs has been summarised. Nanocarriers like liposomes have been widely used and commercialized for human brain cancer treatment. However, nano-inspired structures await their translational recognition. The green synthesis of nanomaterials and their advantages have been discussed. The article highlights the challenges in the nano-modulation of brain cancer and its future outlook.

Synergistic Phenomena between Iron-Doped ZnO Nanoparticles and Shock Waves Exploited against Pancreatic Cancer Cells

We propose the use of iron-doped zinc oxide nanoparticles (Fe:ZnO NPs) showing theranostic capabilities and being synergistically active against pancreatic ductal adenocarcinoma once combined with mechanical pressure waves, such as shock waves. Fe:ZnO NPs are synthesized by employing oleic acid as a capping agent and are functionalized with amino-propyl groups. We first report their superior characteristics with respect to undoped ZnO NPs in terms of magnetic properties, colloidal stability, cytocompatibility, and internalization into BxPC-3 pancreatic cancer cells in vitro. These Fe:ZnO NPs are also cytocompatible toward normal pancreatic cells. We then perform a synergistic cell treatment with both shock waves and Fe:ZnO NPs once internalized into cells. We also evaluate the contribution to the synergistic activity of the NPs located in the extracellular space. Results show that both NPs and shock waves, when administered separately, are safe to cells, while their combination provokes an enhanced cell death after 24 h. Various mechanisms are then considered, such as dissolution of NPs, production of free radicals, and cell membrane disruption or permeation. It is understood so far that iron-doped ZnO NPs can degrade intracellularly into zinc cations, while the use of shock waves produce cell membrane permeabilization and possible rupture. In contrast, the production of reactive oxygen species is here ruled out. The provoked cell death can be recognized in both apoptotic and necrotic events. The proposed work is thus a first proof-of-concept study enabling promising future applications to deep-seated tumors such as pancreatic cancer, which is still an unmet clinical need with a tremendous death rate.

Organic/Inorganic Self-Assembled Hybrid Nano-Architectures for Cancer Therapy Applications

Since the conceptualization of nanomedicine, numerous nanostructure-mediated drug formulations have progressed into clinical trials for treating cancer. However, recent clinical trial results indicate such kind of drug formulations has a limited improvement on the antitumor efficacy. This is due to the biological barriers associated with those formulations, for example, circulation stability, extravasation efficiency in tumor, tumor penetration ability, and developed multi-drug resistance. When employing for nanomedicine formulations, pristine organic-based and inorganic-based nanostructures have their own limitations. Accordingly, organic/inorganic (O/I) hybrids have been developed to integrate the merits of both, and to minimize their intrinsic drawbacks. In this context, the recent development in O/I hybrids resulting from a self-assembly strategy will be introduced. Through such a strategy, organic and inorganic building blocks can be self-assembled via either chemical covalent bonds or physical interactions. Based on the self-assemble procedure, the hybridization of four organic building blocks including liposomes, micelles, dendrimers, and polymeric nanocapsules with five functional inorganic nanoparticles comprising gold nanostructures, magnetic nanoparticles, carbon-based materials, quantum dots, and silica nanoparticles will be highlighted. The recent progress of these O/I hybrids in advanced modalities for combating cancer, such as, therapeutic agent delivery, photothermal therapy, photodynamic therapy, and immunotherapy will be systematically reviewed.

Green nanomedicine: the path to the next generation of nanomaterials for diagnosing brain tumors and therapeutics?

Introduction: Current brain cancer treatments, based on radiotherapy and chemotherapy, are sometimes successful, but they are not free of drawbacks.Areas covered: Traditional methods for the treatment of brain tumors are discussed here with new solutions presented, among which the application of nanotechnology has demonstrated promising results over the past decade. The traditional synthesis of nanostructures, which relies on the use of physicochemical methodologies are discussed, and their associated concerns in terms of environmental and health impact due to the production of toxic by-products, need for toxic catalysts, and their lack of biocompatibility are presented. An overview of the current situation for treating brain tumors using nanotechnological-based approaches is introduced, and some of the latest advances in the application of green nanomaterials (NMs) for the effective targeting of brain tumors are presented.Expert opinion: Green nanotechnology is introduced as a potential solution to toxic NMs through the application of environmentally friendly and cost-effective protocols using living organisms and biomolecules. The current status of this field, such as those involving clinical trials, is included, and the possible limitations of green-NMs and potential ways to avoid those limitations are discussed so that the field can potentially evolve.

Nanomedicine: Bioavailability, Biotransformation and Biokinetics

BACKGROUND

Nanomedicine is increasingly used to treat various ailments. Biocompatibility of nanomedicine is primarily governed by its properties such as bioavailability, biotransformation and biokinetics. One of the major advantages of nanomedicine is enhanced bioavailability of drugs. Biotransformation of nanomedicine is important to understand the pharmacological effects of nanomedicine. Biokinetics includes both pharmacokinetics and toxicokinetics of nanomedicine. Physicochemical parameters of nanomaterials have extensive influence on bioavailability, biotransformation and biokinetics of nanomedicine.

METHODS

We carried out a structured peer-reviewed research literature survey and analysis using bibliographic databases.

RESULTS

Eighty papers were included in the review. Papers dealing with bioavailability, biotransformation and biokinetics of nanomedicine are found and reviewed. Bioavailability and biotransformation along with biokinetics are three major factors that determine the biological fate of nanomedicine. Extensive research work has been done for drugs of micron size but studies on nanomedicine are scarce. Therefore, more emphasis in this review is given on the bioavailability and biotransformation of nanomedicine along with biokinetics.

CONCLUSION

Bioavailability results based on various nanomedicine are summarized in the present work. Biotransformation of nanodrugs as well as nanoformulations is also the focus of this article. Both in vitro and in vivo biotransformation studies on nanodrugs and its excipients are necessary to know the effect of metabolites formed. Biokinetics of nanomedicine is captured in details that are complimentary to bioavailability and biotransformation. Nanomedicine has the potential to be developed as a personalized medicine once its physicochemical properties and its effect on biological system are well understood.

Targeted Theranostic Nanoparticles for Brain Tumor Treatment

The poor prognosis and rapid recurrence of glioblastoma (GB) are associated to its fast-growing process and invasive nature, which make difficult the complete removal of the cancer infiltrated tissues. Additionally, GB heterogeneity within and between patients demands a patient-focused method of treatment. Thus, the implementation of nanotechnology is an attractive approach considering all anatomic issues of GB, since it will potentially improve brain drug distribution, due to the interaction between the blood⁻brain barrier and nanoparticles (NPs). In recent years, theranostic techniques have also been proposed and regarded as promising. NPs are advantageous for this application, due to their respective size, easy surface modification and versatility to integrate multiple functional components in one system. The design of nanoparticles focused on therapeutic and diagnostic applications has increased exponentially for the treatment of cancer. This dual approach helps to understand the location of the tumor tissue, the biodistribution of nanoparticles, the progress and efficacy of the treatment, and is highly useful for personalized medicine-based therapeutic interventions. To improve theranostic approaches, different active strategies can be used to modulate the surface of the nanotheranostic particle, including surface markers, proteins, drugs or genes, and take advantage of the characteristics of the microenvironment using stimuli responsive triggers. This review focuses on the different strategies to improve the GB treatment, describing some cell surface markers and their ligands, and reports some strategies, and their efficacy, used in the current research.

Theranostic niosomes for direct intratumoral injection: marked enhancement in tumor retention and anticancer efficacy

AIM

For simultaneous bioimaging and drug delivery via direct intratumoral injection, doxorubicin and Ag₂S quantum dots co-loaded multifunctional niosomes were prepared and fully characterized.

MATERIALS & METHODS

Various theranostic niosomes were prepared and investigated regarding cytotoxicity, in vivo imaging, drug accumulation in breast cancer tumor and antitumor activity.

RESULTS

Niosomes composed of Tween-60, Tween-80 or Span 60 produced strong and more durable detectable fluorescence signals. Despite a higher accumulation of Tween-60 niosomes in tumor, the Span 60 formulation showed the highest antitumor efficacy when compared with the free drug (71.7 and 20.3% inhibition in tumor growth, respectively).

CONCLUSION

Direct intratumoral injection of theranostic niosomes with appropriate composition could be a powerful tool for combined multimodal imaging and therapy.

Magnetic lipid nanocapsules (MLNCs): self-assembled lipid-based nanoconstruct for non-invasive theranostic applications

A novel magnetic nanostructures (MNS) stabilized lipid nanoconstruct is reported that shows superior structural stability and theranostic functionality than conventional lipid based nanocarriers.

Anti-MRSA malleable liposomes carrying chloramphenicol for ameliorating hair follicle targeting

Pathogens usually invade hair follicles when skin infection occurs. The accumulated bacteria in follicles are difficult to eradicate. The present study aimed to assess the cutaneous and follicular delivery of chloramphenicol (Cm)-loaded liposomes and the antibacterial activity of these liposomes against methicillin-resistant Staphylococcus aureus (MRSA). Skin permeation was conducted by in vitro Franz diffusion cell. The anti-MRSA potential was checked using minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), a well diffusion test, and intracellular MRSA killing. The classic, dimyristoylphosphatidylcholine (DMPC), and deoxycholic acid (DA) liposomes had a vesicle size of 98, 132, and 239 nm, respectively. The incorporation of DMPC or DA into the liposomes increased the bilayer fluidity. The malleable vesicles containing DMPC and DA showed increased follicular Cm uptake over the control solution by 1.5- and 2-fold, respectively. The MIC and MBC of DA liposomes loaded with Cm were 62.5 and 62.5–125 μg/mL, comparable to free Cm. An inhibition zone about 2-fold higher was achieved by DA liposomes as compared to the free control at a Cm dose of 0.5 mg/mL. DA liposomes also augmented antibacterial activity on keratinocyte-infected MRSA. The deformable liposomes had good biocompatibility against keratinocytes and neutrophils (viability >80%). In vivo administration demonstrated that DA liposomes caused negligible toxicity on the skin, based on physiological examination and histology. These data suggest the potential application of malleable liposomes for follicular targeting and the treatment of MRSA-infected dermatologic conditions.

Synthesis, properties and biomedical applications of carbon-based quantum dots: An updated review

Carbon-based quantum dots (CQDs) are a newly developed class of carbon nano-materials that have attracted much interest and attention as promising competitors to already available semiconductor quantum dots owing to their un-comparable and unique properties. In addition, controllability of CQDs unique physiochemical properties is as a result of their surface passivation and functionalization. This is an update article (between 2013 and 2016) on the recent progress, characteristics and synthesis methods of CQDs and different advantages in varieties of applications.

Transition from passive to active targeting of oral insulin nanomedicines: enhancement in bioavailability and glycemic control in diabetes

Oral insulin nanomedicines are effective tools for therapy and management of both Type I and Type II diabetes. This review summarizes the various nanocarriers developed so far in the literature for oral delivery of insulin. It includes lipid-based (i.e., solid lipid nanoparticles and liposomes) and polymeric-based insulin nanomedicines (i.e., chitosan nanoparticles, alginate nanoparticles, dextran nanoparticles and nanoparticles of synthetic polymers) for sustained, controlled and targeted oral delivery of insulin. Mainly, goblet cell-targeting, vitamin B12 receptor-targeting, folate receptor-targeting and transferrin receptor-targeting aspects were focused. Currently, passive and active targeting approaches of oral insulin nanomedicines have improved the oral absorption of insulin and its bioavailability (up to 14%) that produced effective glycaemic control in in vivo models. These results indicate a promising future of oral insulin nanomedicines for the treatment of diabetes.

Meta-analysis of cellular toxicity for cadmium-containing quantum dots

Understanding the relationships between the physicochemical properties of engineered nanomaterials and their toxicity is critical for environmental and health risk analysis. However, this task is confounded by material diversity, heterogeneity of published data and limited sampling within individual studies. Here, we present an approach for analysing and extracting pertinent knowledge from published studies focusing on the cellular toxicity of cadmium-containing semiconductor quantum dots. From 307 publications, we obtain 1,741 cell viability-related data samples, each with 24 qualitative and quantitative attributes describing the material properties and experimental conditions. Using random forest regression models to analyse the data, we show that toxicity is closely correlated with quantum dot surface properties (including shell, ligand and surface modifications), diameter, assay type and exposure time. Our approach of integrating quantitative and categorical data provides a roadmap for interrogating the wide-ranging toxicity data in the literature and suggests that meta-analysis can help develop methods for predicting the toxicity of engineered nanomaterials.

Fluorescence optical imaging in anticancer drug delivery

In the past several decades, nanosized drug delivery systems with various targeting functions and controlled drug release capabilities inside targeted tissues or cells have been intensively studied. Understanding their pharmacokinetic properties is crucial for the successful transition of this research into clinical practice. Among others, fluorescence imaging has become one of the most commonly used imaging tools in pre-clinical research. The development of increasing numbers of suitable fluorescent dyes excitable in the visible to near-infrared wavelengths of the spectrum has significantly expanded the applicability of fluorescence imaging. This paper focuses on the potential applications and limitations of non-invasive imaging techniques in the field of drug delivery, especially in anticancer therapy. Fluorescent imaging at both the cellular and systemic levels is discussed in detail. Additionally, we explore the possibility for simultaneous treatment and imaging using theranostics and combinations of different imaging techniques, e.g., fluorescence imaging with computed tomography.

New Red-Emitting Conjugated Polyelectrolyte: Stabilization by Interaction with Biomolecules and Potential Use as Drug Carriers and Bioimaging Probes

The design and development of fluorescent conjugated polyelectrolytes (CPEs) emitting in the red region of the visible spectrum is at present of great interest for bioimaging studies. However, despite the wide variety of CPEs available, stable bright red-emitters remain scarce due to their low solubility and instability in aqueous media, consequently limiting their applications. In this work, we have synthesized and characterized a new red-emitting cationic conjugated polyelectrolyte copoly-{[9,9-bis(6'-N,N,N-trimethylammonium)hexyl]-2,7-(fluorene)-alt-1,4-(naphtho[2,3c]-1,2,5-thiadiazole)} bromide (HTMA-PFNT), based on the incorporation of naphtha[2,3c][1,2,5] thiadiazole on fluorene backbone to increase the bathochromic emission, extending the conjugation length in the polymer backbone. Water stabilization was achieved by binding the polyelectrolyte to two different biological systems which are currently used as nanocarriers: human serum albumin (HSA) and lipid vesicles. Using both systems, stable nanostructures of different composition were obtained and their properties were characterized. The properties of the protein-based nanoparticles are consistent with polyelectrolyte aggregates covered with HSA molecules, while the liposome system is composed of lipid vesicles coated with polyelectrolyte chains partially inserted in the bilayer. Both protein and vesicle structural integrity were not affected after their interaction with HTMA-PFNT, as well as the carrier properties, allowing for the binding and transport of ligands. In addition, the nanoparticles displayed the ability of labeling the cell membrane of living cells. All these results extend the potential applications of these novel multifunctional nanoparticles as therapeutic carriers and bioimaging probes.

Multifunctional nanocarriers for simultaneous encapsulation of hydrophobic and hydrophilic drugs in cancer treatment

Combination therapy for cancer patients is an important standard of care protocol because it can elicit synergistic therapeutic effects and reduce systemic toxicity by simultaneously modulating multiple cell-signaling pathways and overcoming multidrug resistance. Nanocarriers are expected to play a major role in delivering multiple drugs to tumor tissues by overcoming biological barriers. However, especially considering the different physical chemistry of chemotherapeutic drugs, it is highly desirable to develop a codelivery nanocarrier for controlled and targeted delivery of both hydrophobic and hydrophilic drugs. This review reports the recent developments in various combinational drug delivery systems and the simultaneous use of combinational drug delivery systems with functional agents.

Liposomes as nanomedical devices

Since their discovery in the 1960s, liposomes have been studied in depth, and they continue to constitute a field of intense research. Liposomes are valued for their biological and technological advantages, and are considered to be the most successful drug-carrier system known to date. Notable progress has been made, and several biomedical applications of liposomes are either in clinical trials, are about to be put on the market, or have already been approved for public use. In this review, we briefly analyze how the efficacy of liposomes depends on the nature of their components and their size, surface charge, and lipidic organization. Moreover, we discuss the influence of the physicochemical properties of liposomes on their interaction with cells, half-life, ability to enter tissues, and final fate in vivo. Finally, we describe some strategies developed to overcome limitations of the “first-generation” liposomes, and liposome-based drugs on the market and in clinical trials.

Quantum dots: bright and versatile in vitro and in vivo fluorescence imaging biosensors

Colourful cells and tissues: semiconductor quantum dots and their versatile applications in multiplexed bioimaging research.

Overview on in vitro and in vivo investigations of nanocomposite based cancer diagnosis and therapeutics

The nanodevices are synthesized using nanocomposites by the researchers around the globe. Most of their applications are related to in vivo visualization and therapy with anticancer drugs in the field of oncology.

Continuing progress toward controlled intracellular delivery of semiconductor quantum dots

The biological applications of luminescent semiconductor quantum dots (QDs) continue to grow at a nearly unabated pace. This growth is driven, in part, by their unique photophysical and physicochemical properties which have allowed them to be used in many different roles in cellular biology including: as superior fluorophores for a wide variety of cellular labeling applications; as active platforms for assembly of nanoscale sensors; and, more recently, as a powerful tool to understand the mechanisms of nanoparticle mediated drug delivery. Given that controlled cellular delivery is at the intersection of all these applications, the latest progress in delivering QDs to cells is examined here. A brief discussion of relevant considerations including the importance of materials preparation and bioconjugation along with the continuing issue of endosomal sequestration is initially provided for context. Methods for the cellular delivery of QDs are then highlighted including those based on passive exposure, facilitated strategies that utilize peptides or polymers and fully active modalities such as electroporation and other mechanically based methods. Following on this, the exciting advent of QD cellular delivery using multiple or combined mechanisms is then previewed. Several recent methods reporting endosomal escape of QD materials in cells are also examined in detail with a focus on the mechanisms by which access to the cytosol is achieved. The ongoing debate over QD cytotoxicity is also discussed along with a perspective on how this field will continue to evolve in the future.

Nanotheranostics - application and further development of nanomedicine strategies for advanced theranostics

Nanotheranostics is to apply and further develop nanomedicine strategies for advanced theranostics. This review summarizes the various nanocarriers developed so far in the literature for nanotheranostics, which include polymer conjugations, dendrimers, micelles, liposomes, metal and inorganic nanoparticles, carbon nanotubes, and nanoparticles of biodegradable polymers for sustained, controlled and targeted co-delivery of diagnostic and therapeutic agents for better theranostic effects with fewer side effects. The theranostic nanomedicine can achieve systemic circulation, evade host defenses and deliver the drug and diagnostic agents at the targeted site to diagnose and treat the disease at cellular and molecular level. The therapeutic and diagnostic agents are formulated in nanomedicine as a single theranostic platform, which can then be further conjugated to biological ligand for targeting. Nanotheranostics can also promote stimuli-responsive release, synergetic and combinatory therapy, siRNA co-delivery, multimodality therapies, oral delivery, delivery across the blood-brain barrier as well as escape from intracellular autophagy. The fruition of nanotheranostics will be able to provide personalized therapy with bright prognosis, which makes even the fatal diseases curable or at least treatable at the earliest stage.