Exploring the Influence of Spacers in EDTA-β-Cyclodextrin Dendrimers: Physicochemical Properties and In Vitro Biological Behavior

The synthesis of a new family of ethylenediaminetetraacetic acid (EDTA) core dimers and G0 dendrimers end-capped with two and four β-cyclodextrin (βCD) moieties was performed by click-chemistry conjugation, varying the spacers attached to the core. The structure analyses were achieved in DMSO-d6 and the self-inclusion process was studied in D2O by 1H-NMR spectroscopy for all platforms. It was demonstrated that the interaction with adamantane carboxylic acid (AdCOOH) results in a guest-induced shift of the self-inclusion effect, demonstrating the full host ability of the βCD units in these new platforms without any influence of the spacer. The results of the quantitative size and water solubility measurements demonstrated the equivalence between the novel EDTA-βCD platforms and the classical PAMAM-βCD dendrimer. Finally, we determined the toxicity for all EDTA-βCD platforms in four different cell lines: two human breast cancer cells (MCF-7 and MDA-MB-231), human cervical adenocarcinoma cancer cells (HeLa), and human lung adenocarcinoma cells (SK-LU-1). The new EDTA-βCD carriers did not present any cytotoxicity in the tested cell lines, which showed that these new classes of platforms are promising candidates for drug delivery.

An Insight into Advances in Developing Nanotechnology Based Therapeutics, Drug Delivery, Diagnostics and Vaccines: Multidimensional Applications in Tuberculosis Disease Management

Tuberculosis (TB), one of the deadliest contagious diseases, is a major concern worldwide. Long-term treatment, a high pill burden, limited compliance, and strict administration schedules are all variables that contribute to the development of MDR and XDR tuberculosis patients. The rise of multidrug-resistant strains and a scarcity of anti-TB medications pose a threat to TB control in the future. As a result, a strong and effective system is required to overcome technological limitations and improve the efficacy of therapeutic medications, which is still a huge problem for pharmacological technology. Nanotechnology offers an interesting opportunity for accurate identification of mycobacterial strains and improved medication treatment possibilities for tuberculosis. Nano medicine in tuberculosis is an emerging research field that provides the possibility of efficient medication delivery using nanoparticles and a decrease in drug dosages and adverse effects to boost patient compliance with therapy and recovery. Due to their fascinating characteristics, this strategy is useful in overcoming the abnormalities associated with traditional therapy and leads to some optimization of the therapeutic impact. It also decreases the dosing frequency and eliminates the problem of low compliance. To develop modern diagnosis techniques, upgraded treatment, and possible prevention of tuberculosis, the nanoparticle-based tests have demonstrated considerable advances. The literature search was conducted using Scopus, PubMed, Google Scholar, and Elsevier databases only. This article examines the possibility of employing nanotechnology for TB diagnosis, nanotechnology-based medicine delivery systems, and prevention for the successful elimination of TB illnesses.

Synthesis of β-Cyclodextrin-Decorated Dendritic Compounds Based on EDTA Core: A New Class of PAMAM Dendrimer Analogs

In this work, two dendritic molecules containing an ethylenediaminetetraacetic acid (EDTA) core decorated with two and four β-cyclodextrin (βCD) units were synthesized and fully characterized. Copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC) click chemistry under microwave irradiation was used to obtain the target compounds with yields up to 99%. The classical ethylenediamine (EDA) core present in PAMAM dendrimers was replaced by an EDTA core, obtaining platforms that increase the water solubility at least 80 times compared with native βCD. The synthetic methodology presented here represents a convenient alternative for the rapid and efficient construction of PAMAM analogs. These molecules are envisaged for future applications as drug carriers.

Dendrimers: A Neuroprotective Lead in Alzheimer Disease: A Review on its Synthetic approach and Applications

Alzheimer disease is a neurodegenerative disease that is signified by cognitive decline, memory loss, and erratic behavior. Dendrimers are a type of polymer that has a well-defined structure, a high degree of molecular uniformity, and a low polydispersity which have shown to be effective intracellular drug carriers for bring down the in numerous cases. The data reported by the clinical trials and chemical bonds of dendrimers loading and biological properties that may be used in the bringing out the treatment of nano formulation for Alzheimer disease. Below-range dendrimers have an unlocked figure, but higher-range dendrimers have a more globular and dense structure so handling is difficult. Dendrimers are similar in size to a variety of biological structures; for example, fifth-generation polyamidoamine (PAMAM) dendrimers are similar in size and shape to haemoglobin (5.5 nm diameter). Each generation of dendrimer is described in terms of size, shape, molecular weight, and the number of surface functional groups, with increasing growth specified in terms of 'generation number.' In contrast, Hawker and Frechet were the first to report the convergent approach. A stepwise repeating reaction strategy is used to synthesize dendrimers radically from a central core. The value of dendrimers as drug carriers is discussed in this paper. The information presented in this article can provide useful references for further studies on making dendrimers and applications.

Carbosilane Glycodendrimers for Anticancer Drug Delivery: Synthetic Route, Characterization, and Biological Effect of Glycodendrimer-Doxorubicin Complexes

The complexity of drug delivery mechanisms calls for the development of new transport system designs. Here, we report a robust synthetic procedure toward stable glycodendrimer (glyco-DDM) series bearing glucose, galactose, and oligo(ethylene glycol)-modified galactose peripheral units. In vitro cytotoxicity assays showed exceptional biocompatibility of the glyco-DDMs. To demonstrate applicability in drug delivery, the anticancer agent doxorubicin (DOX) was encapsulated in the glyco-DDM structure. The anticancer activity of the resulting glyco-DDM/DOX complexes was evaluated on the noncancerous (BJ) and cancerous (MCF-7 and A2780) cell lines, revealing their promising generation- and concentration-dependent effect. The glyco-DDM/DOX complexes show gradual and pH-dependent DOX release profiles. Fluorescence spectra elucidated the encapsulation process. Confocal fluorescence microscopy demonstrated preferential cancer cell internalization of the glyco-DDM/DOX complexes. The conclusions were supported by computer modeling. Overall, our results are consistent with the assumption that novel glyco-DDMs and their drug complexes are very promising in drug delivery and related applications.

Nanoarchitectures in Management of Fungal Diseases: An Overview

Fungal infections, from mild itching to fatal infections, lead to chronic diseases and death. Antifungal agents have incorporated chemical compounds and natural products/phytoconstituents in the management of fungal diseases. In contrast to antibacterial research, novel antifungal drugs have progressed more swiftly because of their mild existence and negligible resistance of infections to antifungal bioactivities. Nanotechnology-based carriers have gained much attention due to their magnificent abilities. Nanoarchitectures have served as excellent carriers/drug delivery systems (DDS) for delivering antifungal drugs with improved antifungal activities, bioavailability, targeted action, and reduced cytotoxicity. This review outlines the different fungal diseases and their treatment strategies involving various nanocarrier-based techniques such as liposomes, transfersomes, ethosomes, transethosomes, niosomes, spanlastics, dendrimers, polymeric nanoparticles, polymer nanocomposites, metallic nanoparticles, carbon nanomaterials, and nanoemulsions, among other nanotechnological approaches.

Guest-Mediated Reversal of the Tumbling Process in Phosphorus-Dendritic Compounds Containing β-Cyclodextrin Units: An NMR Study

The conformational study of dendritic platforms containing multiple β-cyclodextrin (βCD) units in the periphery is relevant to determine the availability of βCD cavities for the formation of inclusion complexes in aqueous biological systems. In this work, we performed a detailed conformational analysis in D2O, via 1D and 2D NMR spectroscopy of a novel class of phosphorus dendritic compounds of the type P3N3-[O-C6H4-O-(CH2)n-βCD]6 (where n = 3 or 4). We unambiguously demonstrated that a functionalized glucopyranose unit of at least one βCD unit undergoes a 360° tumbling process, resulting in a deep inclusion of the spacer that binds the cyclodextrin to the phosphorus core inside the cavity, consequently limiting the availability of the inner cavities. In addition, we confirmed through NMR titrations that this tumbling phenomenon can be reversed for all βCD host units using a high-affinity guest, namely 1-adamantanecarboxylic acid (AdCOOH). Our findings have demonstrated that it is possible to create a wide variety of multi-functional dendritic platforms.

Dendrimers based cancer nanotheranostics: An overview

Cancer is a known deadliest disease that requires a judicious diagnostic, targeting, and treatment strategy for an early prognosis and selective therapy. The major pitfalls of the conventional approach are non-specificity in targeting, failure to precisely monitor therapy outcome, and cancer progression leading to malignancies. The unique physicochemical properties offered by nanotechnology derived nanocarriers have the potential to radically change the landscape of cancer diagnosis and therapeutic management. An integrative approach of utilizing both diagnostic and therapeutic functionality using a nanocarrier is termed as nanotheranostic. The nanotheranostics platform is designed in such a way that overcomes various biological barriers, efficiently targets the payload to the desired locus, and simultaneously supports planning, monitoring, and verification of treatment delivery to demonstrate an enhanced therapeutic efficacy. Thus, a nanotheranostic platform could potentially assist in drug targeting, image-guided focal therapy, drug release and distribution monitoring, predictionof treatment response, and patient stratification. A class of highly branched nanocarriers known as dendrimers is recognized as an advanced nanotheranostic platform that has the potential to revolutionize the oncology arena by its unique and exciting features. A dendrimer is a well-defined three-dimensional globular chemical architecture with a high level of monodispersity, amenability of precise size control, and surface functionalization. All the dendrimer properties exhibit a reproducible pharmacokinetic behavior that could ensure the desired biodistribution and efficacy. Dendrimers are thus being exploited as a nanotheranostic platform embodying a diverse class of therapeutic, imaging, and targeting moieties for cancer diagnosis and treatment.

A pilot study of the antiviral activity of anionic and cationic polyamidoamine dendrimers against the Middle East respiratory syndrome coronavirus

The Middle East respiratory syndrome coronavirus (MERS-CoV) is an emerging virus that causes infection with a potentially fatal outcome. Dendrimers are highly branched molecules that can be added to antiviral preparations to improve their delivery, as well as their intrinsic antiviral activity. Studies on identifying anti-MERS-CoV agents are few. Three types of polyanionic dendrimers comprising the terminal groups sodium carboxylate (generations 1.5, 2.5, 3.5, and 4.5), hydroxyl (generations 2, 3, 4, and 5), and succinamic acid (generations 2, 3, 4, and 5) and polycationic dendrimers containing primary amine (generations 2, 3, 4, and 5) were used to assess their antiviral activity with the MERS-CoV plaque inhibition assay. The hydroxyl polyanionic set showed a 17.36% to 29.75% decrease in MERS-CoV plaque formation. The most potent inhibition of MERS-CoV plaque formation was seen by G(1.5)-16COONa (40.5% inhibition), followed by G(5)-128SA (39.77% inhibition). In contrast, the cationic dendrimers were cytotoxic to Vero cells. Polyanionic dendrimers can be added to antiviral preparations to improve the delivery of antivirals, as well as the intrinsic antiviral activity.

A novel dendrimer-based complex co-modified with cyclic RGD hexapeptide and penetratin for noninvasive targeting and penetration of the ocular posterior segment

Noninvasive drug delivery is a promising treatment strategy for ocular posterior segment diseases. Many physiological and anatomical barriers of the eye considerably restrict effective diffusion of therapeutics to the target site. To overcome this problem, a novel cyclic arginine-glycine-aspartate (RGD) hexapeptide and penetratin (PEN) co-modified PEGylation polyamidoamine (PAMAM) was designed as a nanocarriers (NCs), and its penetrating and targeting abilities were evaluated. In this study, we show that PAMAM-PEG (reaction molar ratio 1:32) has a relatively high grafting efficiency and low cytotoxicity. The particle size was within the range of 15-20 nm after modification with RGD and PEN. Cellular uptake of RGD-modified NCs involved significant affinity toward integrin αvβ3, which validated the targeting of neovasculature. An in vitro permeation study indicated that modification with PEN significantly improved penetration of the NCs (1.5 times higher). In vivo ocular distribution studies showed that, the NCs (modified with PEN or co-modified with RGD and PEN) were highly distributed in the cornea and retina (p < .001), and modification extended retinal retention time for more than 12 h. Therefore, these NCs appear to be a promising noninvasive ocular drug delivery system for ocular posterior segment diseases.

Dendrimer Based Nanoarchitectures in Diabetes Management: An Overview

Diabetes has turned out to be one of the biggest worldwide health and economic burdens, with its expanded predominance and high complexity proportion. The quantity of diabetic patients is expanding enormously around the world. Several reports have demonstrated the sharp increment in the sufferers. Stable and acceptable blood glucose control is fundamental to diminish diabetes-related complications. Consequently, ceaseless endeavors have been made in antidiabetic drugs, treatment strategies, and nanotechnology based products to accomplish better diabetes control. The nanocarriers pertaining hypoglycaemics provide improved diabetes management with minimum risk of associated side effects. Dendrimers have caught an incredible attention in the field of drug delivery and personalized medicines. Dendrimers are three-dimensional well-defined homogenous nanosized structures consisting tree-like branches. The present review highlights the different aspects of dendrimers including fabrication, surface engineering, toxicological profile as well as delivery of antidiabetic drugs for the effective cure of diabetes.

Exploration of biomedical dendrimer space based on in-vitro physicochemical parameters: key factor analysis (Part 1)

Dendrimers are highly branched, star-shaped macromolecules with nanometer-scale dimensions that can be readily modified with a range of functional groups, thus modifying their physicochemical and biological properties. In nanomedicine, dendrimers can be used as vectors for the targeted delivery strategy of a variety of biologically active agents or can be used as drug per se. In the future, it will be necessary to designate and develop 'safe' dendrimers, which is currently a crucial concern. Here, we analyze the key in vitro physicochemical parameters to be considered for preclinical evaluation of biomedical dendrimers.

Exploration of biomedical dendrimer space based on in-vivo physicochemical parameters: Key factor analysis (Part 2)

In nanomedicine, the widespread concern of nanoparticles in general, and dendrimers, in particular, is the analysis of key in-vivo physicochemical parameters to ensure the preclinical and clinical development of 'safe' bioactive nanomaterials. It is clear that for biomedical applications, biocompatible dendrimers, used as nanocarriers or active per se, should be devoid of toxicity and immunogenicity, and have adequate PK/PD behaviors (adequate exposure) in order to diffuse in different tissues. Functionalization of dendrimers has a dramatic effect on in-vivo physicochemical parameters. In this review, we highlighted key in-vivo physicochemical properties, based on data from biochemical, cellular and animal models, to provide biocompatible dendrimers. Up-to-date, only scarce studies have been described on this topic.

Bench-to-bedside translation of dendrimers: Reality or utopia? A concise analysis

Nanomedicine, which is an application of nanotechnologies in healthcare is developed to improve the treatments and lives of patients suffering from a range of disorders and to increase the successes of drug candidates. Within the nanotechnology universe, the remarkable unique and tunable properties of dendrimers have made them promising tools for diverse biomedical applications such as drug delivery, gene therapy and diagnostic. Up-to-date, very few dendrimers has yet gained regulatory approval for systemic administration, why? In this critical review, we briefly focus on the list of desired basic dendrimer requirements for decision-making purpose by the scientists (go/no-go decision), in early development stages, to become clinical candidates, and to move towards Investigational New Drugs (IND) application submission. In addition, the successful translation between research and clinic should be performed by the implementation of a simple roadmap to jump the 'valley of death' successfully.

Perspectives of Dendrimer-based Nanoparticles in Cancer Therapy

Currently, cancer is the second most common cause of death in the United States, exceeded only by heart disease. Chemotherapy traditionally suffers from a non-specific distribution, with only a small fraction of the drug reaching the tumor, in this sense, the use of dendrimers incorporating drugs non-covalently encapsulated inside the dendrimer or covalently conjugated have proven to be effectives against different cancer cell lines. However, at present the dendrimers used as drug-carriers still do not meet the necessary characteristic to be considered as an ideal dendrimer for drug delivery; high toxicity, bio-degradability, low toxicity, biodistribution characteristics, and favorable retention with appropriate specificity and bioavailability have not been fully covered by the current available dendrimers. However, the development and study of new dendrimers drug-carriers continues to be an important tool in the cancer therapy as they can be functionalized with varied ligands to reach the tumor tissue through the different body barriers in the body with minimal loss of activity in the bloodstream, have the ability to selectively kill tumor cells without affecting the normal cells and most important with a release mechanism controlling actively. Given the continuous efforts and research in this area of interest, we presented in this review the work done with a special emphasis on the development of dendrimers as a major tool in the combination with drugs, as a potential adjunctive agent in anticancer therapy.

Polymersome-based drug-delivery strategies for cancer therapeutics

Polymersomes are stable vesicles prepared from amphiphilic polymers and are more stable compared with liposomes. Although these nanovesicles have many attractive properties for in vitro/in vivo applications, liposome-based drug delivery systems are still prevalent in the market. In order to expedite the translational potential and to provide medically valuable formulations, the polymersomes need to be biocompatible and biodegradable. In this review, recent developments for biocompatible and biodegradable polymersomes, including the design of intelligent, targeted, and stimuli-responsive vesicles are summarized.

Dendritic Polymers for Theranostics

Dendritic polymers are highly branched polymers with controllable structures, which possess a large population of terminal functional groups, low solution or melt viscosity, and good solubility. Their size, degree of branching and functionality can be adjusted and controlled through the synthetic procedures. These tunable structures correspond to application-related properties, such as biodegradability, biocompatibility, stimuli-responsiveness and self-assembly ability, which are the key points for theranostic applications, including chemotherapeutic theranostics, biotherapeutic theranostics, phototherapeutic theranostics, radiotherapeutic theranostics and combined therapeutic theranostics. Up to now, significant progress has been made for the dendritic polymers in solving some of the fundamental and technical questions toward their theranostic applications. In this review, we briefly summarize how to control the structures of dendritic polymers, the theranostics-related properties derived from their structures and their theranostics-related applications.

Dendrimer-mediated approaches for the treatment of brain tumor

Worldwide, the cancer appeared as one of the most leading cause of morbidity and mortality. Among the various cancer types, brain tumors are most life threatening with low survival rate. Every year approximately 238,000 new cases of brain and other central nervous system tumors are diagnosed. The dendrimeric approaches have a huge potential for diagnosis and treatment of brain tumor with targeting abilities of molecular cargoes to the tumor sites and the efficiency of crossing the blood brain barrier and penetration to brain after systemic administration. The various generations of dendrimers have been designed as novel targeted drug delivery tools for new therapies including sustained drug release, gene therapy, and antiangiogenic activities. At present era, various types of dendrimers like PAMAM, PPI, and PLL dendrimers validated them as milestones for the treatment and diagnosis of brain tumor as well as other cancers. This review highlights the recent research, opportunities, advantages, and challenges involved in development of novel dendrimeric complex for the therapy of brain tumor.

Dendrimer technologies for brain tumor

Despite low prevalence, brain tumors are one of the most lethal forms of cancer. Unfortunately the blood-brain barrier (BBB), a highly regulated, well coordinated and efficient barrier, checks the permeation of most of the drugs across it. Hence, crossing this barrier is one of the most significant challenges in the development of efficient central nervous system therapeutics. Surface-engineered dendrimers improve biocompatibility, drug-release kinetics and aptitude to target the BBB and/or tumors and facilitate transportation of anticancer bioactives across the BBB. This review sheds light on different aspects of brain tumors and dendrimers based on different approaches for treatment including recent research, opportunities and challenges encountered in development of novel and efficient dendrimer-based therapeutics for the treatment of brain tumors.

Designed nucleus penetrating thymine-capped dendrimers: a potential vehicle for intramuscular gene transfection

A nucleus penetrating vehicle is indispensible when seeking to deliver plasmid DNA for gene transfection. In this study, dendrimers with terminal thymine groups were synthesized to meet this objective. Through modifications of the hydrophilic and neutral thymine moieties on hyperbranched peripheries, these dendrimers can achieve biosafety, efficient endosomal escape ability, cytosolic accessibility, and eventually, nuclear entry for the purposes of gene transfection. After optimization of the thymine coverages, better gene expression can only be achieved while replacing ∼50% of the amine groups of a dendrimer with thymine moieties. Presumably, a specific dendrimer comprising thymine and primary amines might possess a synergistic effect to promote pDNA condensation via the cooperation of electrostatic interaction and hydrogen bonding. In comparison, a dendrimer entirely capped by thymine can lose external amines, decreasing pDNA complexity and stability, which would cause poor gene transfection. The utility of specific thymine-capped dendrimers in vivo level was demonstrated to successfully and efficiently deliver plasmid DNA at a low complex ratio into mouse muscle by intramuscular injection. Upon the easy accessibility of intramuscular administration, the capability of thymine-capped dendrimers might be potentially used in immunotherapeutic gene transfection in the future.

Multifunctional hybrid-carbon nanotubes: new horizon in drug delivery and targeting

Carbon nanotubes (CNTs) have emerged as an intriguing nanotechnological tool for numerous biomedical applications including biocompatible modules for the bioactives delivery ascribed to their unique properties, such as greater loading efficiency, biocompatibility, non-immunogenicity, high surface area and photoluminescence, that make them ideal candidate in pharmaceutical and biomedical science. The design of multifunctional hybrid-CNTs for drug delivery and targeting may differ from the conventional drug delivery system. The conventional nanocarriers have few limitations, such as inappropriate availability of surface-chemical functional groups for conjugation, low entrapment/loading efficiency as well as stability as per ICH guidelines with generally regarded as safe (GRAS) prominences. The multifunctional hybrid-CNTs will sparked and open a new door for researchers, scientist of the pharmaceutical and biomedical arena. This review summarizes the vivid aspects of CNTs like characterization, supramolecular chemistry of CNTs-dendrimer, CNTs-nanoparticles, CNTs-quantum dots conjugate for delivery of bioactives, not discussed so far.

Characterizing the interactions of organic nanoparticles with renal epithelial cells in vivo

Nanotechnology approaches are actively being pursued for drug delivery, novel diagnostics, implantable devices, and consumer products. While considerable research has been performed on the effects of these materials on targeted tumor or phagocytic cells, relatively little is known about their effects on renal cells. This becomes critical for supersmall nanoparticles (<10 nm), designed to be renally excreted. The active endocytic machinery of kidney proximal tubules avidly internalizes filtered proteins, which may also be the case for filtered nanoparticles. To test whether such interactions affect kidney function, we injected mice with either 5 nm dextran-based nanoparticles (DNP) that are similar in composition to FDA-approved materials or poly(amido amine) dendrimer nanoparticles (PNP) of comparable size. These fluorescently tagged nanoparticles were both filtered and internalized by renal tubular epithelial cells in a dose- and time-dependent fashion. The biological effects were quantitated by immunocytochemistry, measuring kidney injury markers and performing functional tests. DNP administration resulted in a dose-dependent increase in urinary output, while cellular albumin endocytosis was increased. The expression of megalin, a receptor involved in albumin uptake, was also increased, but AQP1 expression was unaffected. The effects after PNP administration were similar but additionally resulted in increased clathrin expression and increased endocytosis of dextran. We conclude that there are no major detrimental renal effects of DNP on overall kidney function, but changes in endocytosis-mediating protein expression do occur. These studies provide a framework for the testing of additional nanoparticle preparations as they become available.

siRNA nanotherapeutics: a Trojan horse approach against HIV

The concept of RNA interference (RNAi) is gaining popularity for the better management of various diseases, including HIV. Currently, the successful biomedical utilization of siRNA therapeutics is hampered, both in vivo and in vitro, mainly by the inherent inability of naked siRNA to cross the cell membrane. RNAi can potentially improve the weakness of current highly active antiretroviral therapy (HAART) by diminishing the chances of the appearance of antiHIV-resistant strains. Here, we discuss the nanocarrier-mediated delivery of siRNA delivery as well as highlighted the scope of siRNA-mediated gene-silencing technology for improved HIV treatment.

The development, characterization and in vivo anti-ovarian cancer activity of poly(propylene imine) (PPI)-antibody conjugates containing encapsulated paclitaxel

Mesothelin, protein is frequently expressed in ovarian cancers. However, a full understanding of the biological functions of mesothelin is lacking. Here, we investigate the drug targeting potential of antibody conjugated modified half-generation poly (propylene imine) dendrimers i.e. immunodendrimers toward ovarian cancer with a model anti-cancer agent, paclitaxel (PTX). The synthesized plain 4.5G dendrimers as well as immunodendrimers were characterized by FT-IR, (1)H-NMR, TEM, and flow cytometry. Immunodendrimers exhibited considerably reduced hemolytic-, hepato- and nephrotoxicity. MTT cytotoxicity, flow cytometry and cell morphology studies were conducted in OVACAR-3 and A-431 cell. We demonstrate that PTX loaded immunodendrimers reduced the tumor volume significantly. The biodistribution studies further confirmed the targeting efficiency and higher biodistribution of immunodendrimers into the mesothelin protein expressing ovarian cancer cells. The results concluded that the developed immunodendrimers have potential to deliver significantly higher amount of the bioactive and have improved therapeutic outcome.

Receptor-based targeting of therapeutics

Receptor-based targeting of therapeutics may be a fascinating proposition to improve the therapeutic efficacy of encapsulated drugs. The development of safe and effective nanomedicines is a prerequisite in the current nanotechnological scenario. Currently, the surface engineering of nanocarriers has attracted great attention for targeted therapeutic delivery by selective binding of targeting ligand to the specific receptors present on the surface of cells. In this review, we have discussed the current status of various receptors such as transferrin, lectoferrin, lectin, folate, human EGF receptor, scavenger, nuclear and integrin, which are over-expressed on the surface of cancer cells; along with the relevance of targeted delivery systems such as nanoparticles, polymersomes, dendrimers, liposomes and carbon nanotubes. The review also focuses on the effective utilization of receptor-based targeted delivery systems for the management of cancer in effective ways by minimizing the drug-associated side effects and improving the therapeutic efficacy of developed nano-architectures.

Dendrimer-enabled DNA delivery and transformation of Chlamydia pneumoniae

The chlamydiae are important human pathogens. Lack of a genetic manipulation system has impeded understanding of the molecular bases of virulence for these bacteria. We developed a dendrimer-enabled system for transformation of chlamydiae and used it to characterize the effects of inserting the C. trachomatis plasmid into C. pneumoniae, which lacks any plasmids. The plasmid was cloned into modified yeast vector pEG(KG) and the clone complexed to polyamidoamine dendrimers, producing 50-100 nm spherical particles. HEp-2 cell cultures were infected with C. pneumoniae strain AR-39. Twenty-four hours later, medium was replaced for 3 hours with dendrimer-plasmid complexes, then removed and the medium replaced. Cultures were harvested at various times post-transformation. Real-time PCR and RT-PCR of nucleic acids from transformed cultures demonstrated plasmid replication and gene expression. The cloned plasmid was replicated and expressed in transformants over 5 passages. This system will allow study of chlamydial gene function, allowing development of novel dendrimer-based therapies.

FROM THE CLINICAL EDITOR

This team of investigators developed a dendrimer-enabled system for transformation of chlamydiae and successfully utilized it to characterize the effects of inserting the C. trachomatis plasmid into C. pneumonia. This system will allow study of chlamydial gene function, allowing development of novel dendrimer-based therapies.

Inclusion complexes of isoflavones with two commercially available dendrimers: Solubility, stability, structures, release behaviors, cytotoxicity, and anti-oxidant activities

We prepared and characterized the inclusion complexes of daidzein with poly(amidoamine) (PAMAM) and poly(propylene imine) (PPI) dendrimers. Aqueous solubility of daidzein was significantly enhanced by both PAMAM and PPI (186- and 650-fold at 0.36mM, respectively). Daidzein in G3 PAMAM solution is more stable than that in G4 PPI. NMR studies reveal the encapsulation of daidzein within the interior cavities of PPI through hydrophobic interactions. Daidzein exhibits a slower release behavior from PPI than that from PAMAM. PPI/daidzein complex is much more toxic than PAMAM/daidzein complex on several cell lines. PAMAM/daidzein complexes showed similar protective effect on oxidative stress-induced cytotoxicity as compared to free daidzein. These results suggest that the inclusion of daidzein with dendrimer can effectively improve the solubility, prolong the delivery, and maintain the anti-oxidant activity of daidzein. This research provides new insights into dendrimer-based drug delivery systems and will be helpful for the design of novel dendrimer/drug formulations.