The novel albumin-chitosan core-shell nanoparticles for gene delivery: preparation, optimization and cell uptake investigation

Novel Gene Therapy Approaches for Targeting Neurodegenerative Disorders: Focusing on Delivering Neurotrophic Genes

Neurodegenerative illnesses (NDDs) like Alzheimer's, Parkinson's, amyotrophic lateral sclerosis, spinal muscular atrophy, and Huntington's disease have demonstrated considerable potential for gene therapy as a viable therapeutic intervention. NDDs are marked by the decline of neurons, resulting in changes in both behavior and pathology within the body. Strikingly, only symptomatic management is available without a cure for the NDDs. There is an unmet need for a permanent therapeutic approach. Many studies have been going on to target the newer therapeutic molecular targets for NDDs including gene-based therapy. Gene therapy has the potential to provide therapeutic benefits to a large number of patients with NDDs by offering mechanisms including neuroprotection, neuro-restoration, and rectification of pathogenic pathways. Gene therapy is a medical approach that aims to modify the biological characteristics of living cells by controlling the expression of specific genes in certain neurological disorders. Despite being the most complex and well-protected organ in the human body, there is clinical evidence to show that it is possible to specifically target the central nervous system (CNS). This provides hope for the prospective application of gene therapy in treating NDDs in the future. There are several advanced techniques available for using viral or non-viral vectors to deliver the therapeutic gene to the afflicted region. Neurotrophic factors (NTF) in the brain are crucial for the development, differentiation, and survival of neurons in the CNS, making them important in the context of various neurological illnesses. Gene delivery of NTF has the potential to be used as a therapeutic approach for the treatment of neurological problems in the brain. This review primarily focuses on the methodologies employed for delivering the genes of different NTFs to treat neurological disorders. These techniques are currently being explored as a viable therapeutic approach for neurodegenerative diseases. The article exclusively addresses gene delivery approaches and does not cover additional therapy strategies for NDDs. Gene therapy offers a promising alternative treatment for NDDs by stimulating neuronal growth instead of solely relying on symptom relief from drugs and their associated adverse effects. It can serve as a long-lasting and advantageous treatment choice for the management of NDDs. The likelihood of developing NDDs increases with age as a result of neuronal degradation in the brain. Gene therapy is an optimal approach for promoting neuronal growth through the introduction of nerve growth factor genes.

Experimental design approach for development of carboplatin loaded chitosan modified liposomal formulation with improved topical vaginal therapeutic potential

One of the most prevalent cancers affecting women globally is cervical cancer. Cervical cancer is thought to cause 570 000 new cases annually, and standard treatments can have serious side effects. In this work, the main aim is to design, fabrication, and evaluation of carboplatin loaded chitosan coated liposomal formulation (CCLF-I) for vaginal delivery in the treatment of cervical cancer. The particle size and polydispersity index of the CCLF-1 were observed at 269.33 ± 1.15 and 0.40 ± 0.002 nm, respectively. The in vitro mucin binding studies showed good adhesiveness of CCLF-I as compared to plain liposomes (CPLF-I), which was found at 23.49 and 10.80%, respectively. The ex-vivo percent drug permeation from plain liposomal formulation (CPLF-I) was found to be higher in comparison to chitosan coated liposomal formulation which was 56.33% while in CCLF-I it was observed 47.32% this is due to, higher retainability of delivery system (CCLF-I) on targeted site attained by coating of mucoadhesive polymer on liposomes. Ex vivo tissue retention studies exhibited 24.2% of CCLF-I in comparison to 10.34% from plain drug formulation (CPLF-I). The in vivo vaginal retention studies exhibited 14% of drug retention after 24 h from the novel formulation in comparison to 6% from the plain formulation. The developed CCLF-I formulation would open a new avenue in the cervical treatment.

Development and characterization of polydeoxyribonucleotide (PDRN) loaded chitosan polyplex: In vitro and in vivo evaluation of wound healing activity

Polydeoxyribonucleotide (PDRN) is an accelerated diabetic wound healing therapy with promising abilities to promote cell growth, angiogenesis, collagen synthesis, and reduce inflammation where its sustainable delivery and release behavior is critical to ensure effective wound healing properties. Therefore, a nanopolyplex was developed here, by encapsulating PDRN with chitosan to affirm its delivery systematically. The physicochemical characterization revealed its successful encapsulation which facilitates the gradual release of PDRN. In vitro studies of the polyplex demonstrated no cytotoxicity and enhanced cell proliferation and migration properties with high antimicrobial activities. In vivo, wound healing studies in Wistar rats dorsal skin defect model induced with diabetes mellitus affirm the highest wound healing activity and wound closure rate by chitosan/PDRN polyplex treatment. Considerably high histopathological changes such as epithelialization, collagen deposition, blood vessels, and hair follicle formation were observed under the polyplex treatment. The immunohistochemical analysis for platelet endothelial cell adhesion molecule (CD31) and cluster of differentiation (CD68) revealed the ability of polyplex to increase CD31 expression and decrease CD68 expression thereby promoting the wound healing process. Collectively, these results suggest that significantly accelerated, high-quality wound healing effects could be obtained by the developed chitosan/PDRN polyplex and thus it could be introduced as a potential therapeutic product for diabetic wound healing.

Chitosan-PEI passivated carbon dots for plasmid DNA and miRNA-153 delivery in cancer cells

These days carbon dots have been developed for multiple biomedical applications. In the current study, the transfection potential of synthesized carbon dots from single biopolymers such as chitosan, PEI-2kDa, and PEI-25kDa (CS-CDs, PEI2-CDs, and PEI25-CDs) and by combining two biopolymers (CP2-CDs and CP25-CDs) through a bottom-up approach have been investigated. The characterization studies revealed successful synthesis of fluorescent, positively charged carbon dots <20 nm in size. Synthesized carbon dots formed a stable complex with plasmid DNA (EGFP-N1) and miRNA-153 that protected DNA/miRNA from serum-induced degradation. In-vitro cytotoxicity analysis revealed minimal cytotoxicity in cancer cell lines (A549 and MDA-MB-231). In-vitro transfection of EGFP-N1 plasmid DNA with PEI2-CDs, PEI25-CDs and CP25-CDs demonstrated that these CDs could strongly transfect A549 and MDA-MB-231 cells. The highest EGFP-N1 plasmid transfection efficiency was observed with PEI2-CDs at a weight ratio of 32:1. PEI25-CDs polyplex showed maximum transfection at a weight ratio of 8:1 in A549 at a weight ratio of 16:1 in MDA-MB-231 cells. CP25-CDs exhibited the highest transfection at a weight ratio of 16:1 in both cell lines. The in-vitro transfection of target miRNA, i.e., miR-153 in A549 and MDA-MB-231 cells with PEI2-CDs, PEI25-CDs, and CP25-CDs suggested successful transfer of miR-153 into cells which induced significant cell death in both cell lines. Importantly, CS-CDs and CP2-CDs could be tolerated by cells up to 200 μg/mL concentration, while PEI2-CDs, PEI25-CDs, and CP25-CDs showed non-cytotoxic behavior at low concentrations (25 μg/mL). Together, these results suggest that a combination of carbon dots synthesized from chitosan and PEI (CP25-CDs) could be a novel vector for transfection nucleic acids that can be utilized in cancer therapy.

Innovative biosynthesis, artificial intelligence-based optimization, and characterization of chitosan nanoparticles by Streptomyces microflavus and their inhibitory potential against Pectobacterium carotovorum

Microbial-based strategy in nanotechnology offers economic, eco-friendly, and biosafety advantages over traditional chemical and physical protocols. The current study describes a novel biosynthesis protocol for chitosan nanoparticles (CNPs), employing a pioneer Streptomyces sp. strain NEAE-83, which exhibited a significant potential for CNPs biosynthesis. It was identified as Streptomyces microflavus strain NEAE-83 based on morphological, and physiological properties as well as the 16S rRNA sequence (GenBank accession number: MG384964). CNPs were characterized by SEM, TEM, EDXS, zeta potential, FTIR, XRD, TGA, and DSC. CNPs biosynthesis was maximized using a mathematical model, face-centered central composite design (CCFCD). The highest yield of CNPs (9.41 mg/mL) was obtained in run no. 27, using an initial pH of 5.5, 1% chitosan, 40 °C, and a 12 h incubation period. Innovatively, the artificial neural network (ANN), was used for validating and predicting CNPs biosynthesis based on the trials data of CCFCD. Despite the high precision degree of both models, ANN was supreme in the prediction of CNPs biosynthesis compared to CCFCD. ANN had a higher prediction efficacy and, lower error values (RMSE, MDA, and SSE). CNPs biosynthesized by Streptomyces microflavus strain NEAE-83 showed in-vitro antibacterial activity against Pectobacterium carotovorum, which causes the potato soft rot. These results suggested its potential application for controlling the destructive potato soft rot diseases. This is the first report on the biosynthesis of CNPs using a newly isolated; Streptomyces microflavus strain NEAE-83 as an eco-friendly approach and optimization of the biosynthesis process by artificial intelligence.

Materiomically Designed Polymeric Vehicles for Nucleic Acids: Quo Vadis?

Despite rapid advances in molecular biology, particularly in site-specific genome editing technologies, such as CRISPR/Cas9 and base editing, financial and logistical challenges hinder a broad population from accessing and benefiting from gene therapy. To improve the affordability and scalability of gene therapy, we need to deploy chemically defined, economical, and scalable materials, such as synthetic polymers. For polymers to deliver nucleic acids efficaciously to targeted cells, they must optimally combine design attributes, such as architecture, length, composition, spatial distribution of monomers, basicity, hydrophilic-hydrophobic phase balance, or protonation degree. Designing polymeric vectors for specific nucleic acid payloads is a multivariate optimization problem wherein even minuscule deviations from the optimum are poorly tolerated. To explore the multivariate polymer design space rapidly, efficiently, and fruitfully, we must integrate parallelized polymer synthesis, high-throughput biological screening, and statistical modeling. Although materiomics approaches promise to streamline polymeric vector development, several methodological ambiguities must be resolved. For instance, establishing a flexible polymer ontology that accommodates recent synthetic advances, enforcing uniform polymer characterization and data reporting standards, and implementing multiplexed in vitro and in vivo screening studies require considerable planning, coordination, and effort. This contribution will acquaint readers with the challenges associated with materiomics approaches to polymeric gene delivery and offers guidelines for overcoming these challenges. Here, we summarize recent developments in combinatorial polymer synthesis, high-throughput screening of polymeric vectors, omics-based approaches to polymer design, barcoding schemes for pooled in vitro and in vivo screening, and identify materiomics-inspired research directions that will realize the long-unfulfilled clinical potential of polymeric carriers in gene therapy.

Chitosan-coated bovine serum albumin nanoparticles for topical tetrandrine delivery in glaucoma: in vitro and in vivo assessment

Glaucoma is one of the leading causes of blindness. Therapies available suffer from several drawbacks including low bioavailability, repeated administration and poor patient compliance with adverse effects thereafter. In this study, bovine serum albumin nanoparticles (BSA-NPs) coated with chitosan(CS) were developed for the topical delivery of tetrandrine (TET) for glaucoma management. Optimized nanoparticles were prepared by desolvation. pH, BSA, CS and cross-linking agent concentrations effects on BSA-NPs colloidal properties were investigated. CS-BSA-NPs with particle size 237.9 nm and zeta potential 24 mV was selected for further evaluation. EE% exceeded 95% with sustained release profile. In vitro mucoadhesion was evaluated based on changes in viscosity and zeta potential upon incubation with mucin. Ex vivo transcorneal permeation was significantly enhanced for CS coated formulation. In vitro cell culture studies on corneal stromal fibroblasts revealed NPs biocompatibility with enhanced cellular uptake and improved antioxidant and anti-proliferative properties for the CS-coated formulation. Moreover, BSA-NPs were nonirritant as shown by HET-CAM test. Also, bioavailability in rabbit aqueous humor showed 2-fold increase for CS-TET-BSA-NPs compared to TET with a sustained reduction in intraocular pressure in a rabbit glaucoma model. Overall, results suggest CS-BSA-NPs as a promising platform for topical ocular TET delivery in the management of glaucoma.

Silymarin/curcumin loaded albumin nanoparticles coated by chitosan as muco-inhalable delivery system observing anti-inflammatory and anti COVID-19 characterizations in oleic acid triggered lung injury and in vitro COVID-19 experiment

Respiratory infected by COVID-19 represents a major global health problem at moment even after recovery from virus corona. Since, the lung lesions for infected patients are still sufferings from acute respiratory distress syndrome including alveolar septal edema, pneumonia, hyperplasia, and hyaline membranes Therefore, there is an urgent need to identify additional candidates having ability to overcome inflammatory process and can enhance efficacy in the treatment of COVID-19. The polypenolic extracts were integrated into moeties of bovine serum albumin (BSA) and then were coated by chitosan as a mucoadhesion polymer. The results of interleukin-6, and c-reactive protein showed significant reduction in group treated by Encap. SIL + CUR (64 ± 0.8 Pg/μL & 6 ± 0.5 μg/μL) compared to group treated by Cham. + CUR (102 ± 0.8 Pg/μL & 7 ± 0.5 μg/μL) respectively and free capsules (with no any drug inside) (148 ± 0.6 Pg/μL & 10 ± 0.6 μg/μL) respectively. Histopathology profile was improved completely. Additionally, encapsulating silymarin showed anti-viral activity in vitro COVID-19 experiment. It can be summarized that muco-inhalable delivery system (MIDS) loaded by silymarin can be used to overcome inflammation induced by oleic acid and to overcome COVID-19.

Amino Acids, Peptides, and Proteins: Implications for Nanotechnological Applications in Biosensing and Drug/Gene Delivery

Over various scientific fields in biochemistry, amino acids have been highlighted in research works. Protein, peptide- and amino acid-based drug delivery systems have proficiently transformed nanotechnology via immense flexibility in their features for attaching various drug molecules and biodegradable polymers. In this regard, novel nanostructures including carbon nanotubes, electrospun carbon nanofibers, gold nanoislands, and metal-based nanoparticles have been introduced as nanosensors for accurate detection of these organic compounds. These nanostructures can bind the biological receptor to the sensor surface and increase the surface area of the working electrode, significantly enhancing the biosensor performance. Interestingly, protein-based nanocarriers have also emerged as useful drug and gene delivery platforms. This is important since, despite recent advancements, there are still biological barriers and other obstacles limiting gene and drug delivery efficacy. Currently available strategies for gene therapy are not cost-effective, and they do not deliver the genetic cargo effectively to target sites. With rapid advancements in nanotechnology, novel gene delivery systems are introduced as nonviral vectors such as protein, peptide, and amino acid-based nanostructures. These nano-based delivery platforms can be tailored into functional transformation using proteins and peptides ligands based nanocarriers, usually overexpressed in the specified diseases. The purpose of this review is to shed light on traditional and nanotechnology-based methods to detect amino acids, peptides, and proteins. Furthermore, new insights into the potential of amino protein-based nanoassemblies for targeted drug delivery or gene transfer are presented.

Physicochemical Characteristics of Chitosan-Based Hydrogels Containing Albumin Particles and Aloe vera Juice as Transdermal Systems Functionalized in the Viewpoint of Potential Biomedical Applications

In recent years, many investigations on the development of innovative dressing materials with potential applications, e.g., for cytostatics delivery, have been performed. One of the most promising carriers is albumin, which tends to accumulate near cancer cells. Here, chitosan-based hydrogels containing albumin spheres and Aloe vera juice, designed for the treatment of skin cancers or burn wounds resulting from radiotherapy, were developed. The presence of albumin in hydrogel matrices was confirmed via Fourier transform infrared (FT-IR) and Raman spectroscopy. Albumin spheres were clearly visible in microscopic images. It was proved that the introduction of albumin into hydrogels resulted in their increased resistance to the tensile load, i.e., approximately 30% more force was needed to break such materials. Modified hydrogels showed approximately 10% more swelling ability. All hydrogels were characterized by hydrophilicity (contact angles were <90°) which may support the regeneration of epithelial cells and non-cytotoxicity towards murine fibroblasts L929 and released Aloe vera juice more effectively in an acidic environment than in a neutral one wherein spheres introduced into the hydrogel matrix extended the release time. Thus, the developed materials, due to their chemical composition and physicochemical properties, constitute promising materials with great application potential for biomedical purposes.

Preparation and characterization of paclitaxel palmitate albumin nanoparticles with high loading efficacy: an in vitro and in vivo anti-tumor study in mouse models

BACKGROUND

Combination of the prodrug technique with an albumin nano drug-loaded system is a novel promising approach for cancer treatment. However, the long-lasting and far-reaching challenge for the treatment of cancers lies in how to construct the albumin nanometer drug delivery system with lead compounds and their derivatives.

METHODS

In this study, we reported the preparation of injectable albumin nanoparticles (NPs) with a high and quantitative drug loading system based on the Nab^TM technology of paclitaxel palmitate (PTX-PA).

RESULTS

Our experimental study on drug tissue distribution in vivo demonstrated that the paclitaxel palmitate albumin nanoparticles (Nab-PTX-PA) remained in the tumor for a longer time post-injection. Compared with saline and paclitaxel albumin nanoparticles (Abraxane^®), intravenous injection of Nab-PTX-PA not only reduced the toxicity of the drug in normal organs, and increased the body weight of the animals but maintained sustained release of paclitaxel (PTX) in the tumor, thereby displaying an excellent antitumor activity. Blood routine analysis showed that Nab-PTX-PA had fewer adverse effects or less toxicity to the normal organs, and it inhibited tumor cell proliferation more effectively as compared with commercial paclitaxel albumin nanoparticles.

CONCLUSIONS

This carrier strategy for small molecule drugs is based on naturally evolved interactions between long-chain fatty acids (LCFAs) and Human Serum Albumin (HSA), demonstrated here for PTX. Nab-PTX-PA shows higher antitumor efficacy in vivo in breast cancer models. On the whole, this novel injectable Nab-PTX-PA has great potential as an effective drug delivery system in the treatment of breast cancer.

Preparation and in vitro characterization of histidine trimethyl chitosan conjugated nanocomplex incorporated into injectable thermosensitive hydrogels for localized gene delivery

Localized and sustained delivery of DNA using biomaterial scaffolds would increase the applicability of gene therapy in cancer treatment and tissue engineering. The most promising approach is the application of hydrogel scaffolds to encapsulate and deliver DNA in the form of nanocomplex to the target sites. In the present work, histidine conjugated trimethylated chitosan (HTMC) was synthesized and nanocomplexes fabricated with pDNA at different N/P ratios. The zeta potential and size of the HTMC/pDNA nanoparticles were determined using dynamic light scattering technique and the results were confirmed by scanning electron microscopy (SEM). The morphology of the nanoparticles was found spherical in shape having core-shell nanostructure. Based on gel retardation assay, polyplex dissociation following incubation with heparin, protection against DNase Ι, cytotoxicity and transfection experiments, HTMC/pDNA at N/P 15 was selected as an optimized formulation and loaded into CTS/PF127 and HA/PF127 hydrogel. The optimized HTMC/pDNA nanocomplex was homogenously distributed in the CTS/PF127 hydrogel. Transfection experiments were carried out on HEK293T cell lines and the results revealed that HTMC/pDNA complexes are stable and active inside the hydrogel, however, the transfection efficacy was decreased after incorporation into the hydrogel.

Advanced applications of nanotechnology in veterinary medicine

The invention of new techniques to manipulate materials at their nanoscale had an evolutionary effect on various medical sciences. At the time, there are thousands of nanomaterials which can be divided according to their shape, origin, or their application. The nanotechnology provided new solutions for old problems. In medical sciences, they are used for diagnostic or therapeutic purposes. They can also be applied in the preparation of nanovaccines and nanoadjuvants. Their use in the treatment of cancer and in gene therapy opened the door for a new era in medicine. Recently, various applications of nanotechnology started to find their way in the veterinary sector. They increasingly invade animal therapeutics, diagnostics, production of veterinary vaccines, farm disinfectants, for animal breeding and reproduction, and even the field of animal nutrition. Their replacement of commonly used antibiotics directly reflects on the public health. By so doing, they minimize the problem of drug resistance in both human and veterinary medicine, and the problem of drug residues in milk and meat. In addition, they have a great economic impact, by minimizing the amounts of discarded milk and the number of culled calves in dairy herds. Nanotechnology was also applied to develop pet care products and hygienic articles. The present review discusses the advantage of using nanomaterials compared to their counterparts, the various classes of nanoparticles, and illustrates the applications and the role of nanotechnology in the field of veterinary medicine.

Application of some nanoparticles in the field of veterinary medicine

Nanotechnology is a fast-growing technology that plays an important great impact on various fields of therapeutic applications. It is capable for solving several problems related to animal health and production. There are different nano-systems such as liposomes, metallic nanoparticles, polymeric micelles, polymeric nanospheres, functionalized fullerenes, carbon nanotubes, dendrimers, polymer-coated nanocrystals and nanoshells. In this review, we mentioned different methods for the preparation and characterization of nanoparticles. This review is concerned mainly on nanoparticle systems for antibiotic delivery which suffer from poor bioavailability and many side effects. Nanoparticles are characterized by many features include their minimal size, colossal surface zone to mass extent. The development of antimicrobials in nanoparticle systems is considered an excellent alternative delivery system for antimicrobials for the treatment of microbial diseases by increasing therapeutic effect and overcoming the side effects. In this paper, we reviewed some antimicrobial nanoparticle preparations and we focused on florfenicol and neomycin nanoparticle preparations as well as chitosan and silver nanoparticles preparations to prepare, characterize and compare their different pharmacological effects.

Thaw-Induced Gelation of Alginate Hydrogels for Versatile Delivery of Therapeutics

Alginate hydrogels have been extensively used and successfully validated as delivery vehicles of bioactive factors in many tissue engineering applications. This work describes and characterizes a singular alternative method to create alginate hydrogels designated as thaw-induced gelation (TIG). The TIG method involves gelation through the time-dependent release of the polymer or crosslinker by melting into solution. Alginate TIG hydrogels were validated for spatial-temporal control delivery of different cargos including albumin, dextran, and doxorubicin. Chitosan was incorporated into TIG hydrogels to investigate the electrostatic interactions between alginate and the tested cargos. Interestingly, while 90% of doxorubicin was released after 8 h from hydrogels formed with frozen calcium, hydrogels formulated from frozen alginate took 72 h. In addition, the storage modulus of TIG hydrogels prepared from frozen alginate was double that of a hydrogel formed without freezing alginate. Therefore, the utility of TIG strategies are particularly promising for the delivery of therapeutic cargos smaller than the mesh size of the alginate hydrogel, as it enables controlled release of these cargos without any further chemical modifications of the hydrogels. These TIG alginate hydrogels with tunable mechanical properties and control over the delivery of smaller cargos could be useful in many tissue engineering applications.

Self-Assembled Reduced Albumin and Glycol Chitosan Nanoparticles for Paclitaxel Delivery

Cancer continues to pose health problems for people all over the world. Nanoparticles (NPs) have emerged as a promising platform for effective cancer chemotherapy. NPs formed by the assembly of proteins and chitosan (CH) through noncovalent interactions are attracting a great deal of interest. However, the poor water solubility of CH and low stability of this kind of NP limit its practical application. Herein, the formation of reduced bovine serum albumin (rBSA) and glycol chitosan (GC) nanoparticles (rBG-NPs) stabilized by hydrophobic interactions and disulfide bonds was demonstrated for paclitaxel (PTX) delivery. The effects of the rBSA:GC mass ratio and pH on the particle size, polydispersity index (PDI), number of particles, and surface charge were evaluated. The formation mechanism and stability of the NPs were determined by compositional analysis and dynamic light scattering. Hydrophobic and electrostatic interactions were the driving forces for the formation of the rBG-NPs, and the NPs were stable under physiological conditions. PTX was successfully encapsulated into rBG-NPs with a high encapsulation efficiency (∼90%). PTX-loaded rBG-NPs had a particle size of ∼400 nm with a low PDI (0.2) and positive charge. rBG-NPs could be internalized by HeLa cells, possibly via endocytosis. An in vitro cytotoxicity study revealed that PTX-loaded rBG-NPs had anticancer activity that was lower than that of a Taxol-like formulation at 24 h but had similar activity at 48 h, possibly because of the slow release of PTX into the cells. Our study suggests that rBG-NPs could be used as a potential nanocarrier for hydrophobic drugs.

DNA Vaccines-How Far From Clinical Use?

Two decades ago successful transfection of antigen presenting cells (APC) in vivo was demonstrated which resulted in the induction of primary adaptive immune responses. Due to the good biocompatibility of plasmid DNA, their cost-efficient production and long shelf life, many researchers aimed to develop DNA vaccine-based immunotherapeutic strategies for treatment of infections and cancer, but also autoimmune diseases and allergies. This review aims to summarize our current knowledge on the course of action of DNA vaccines, and which factors are responsible for the poor immunogenicity in human so far. Important optimization steps that improve DNA transfection efficiency comprise the introduction of DNA-complexing nano-carriers aimed to prevent extracellular DNA degradation, enabling APC targeting, and enhanced endo/lysosomal escape of DNA. Attachment of virus-derived nuclear localization sequences facilitates nuclear entry of DNA. Improvements in DNA vaccine design include the use of APC-specific promotors for transcriptional targeting, the arrangement of multiple antigen sequences, the co-delivery of molecular adjuvants to prevent tolerance induction, and strategies to circumvent potential inhibitory effects of the vector backbone. Successful clinical use of DNA vaccines may require combined employment of all of these parameters, and combination treatment with additional drugs.

Biocompatibility studies of intravenously administered ionic-crosslinked chitosan-BSA nanoparticles as vehicles for antitumour drugs

In this study, a new alternative of ionic crosslinked nanoparticles (NPs) based on chitosan (C) and bovine serum albumin (A; BSA) was evaluated as drug delivery system for antitumour compounds (doxorubicin hydrochloride as a model). The different responses to the pH of the medium were determined by the electrostatic interactions induced by each polymeric combination (C50/A50; C80/A20; C20/A80). NPs revealed a nanoscale size (167-392 nm) and a positive net charge (12-26 mV), modulated by doxorubicin (DOX) loading. Drug loading capacity was higher than 5.2 ± 1.8 μgDOX/mgNP (Encapsulation efficiency = 34%), and an initial burst release was followed by a sustained delivery. Cellular uptake assays confirmed the entry of NPs in three human tumor cells (MCF7, T47D and Hela), triggering antioxidant responses (superoxide dismutase, catalase, glutathione reductase and total glutathione content) in those cells. This was also consistent with the decreased in IC50 values observed after the incubation of these cells with C20/A80-DOX and C50/A50-DOX NPs (1.90-3.48 μg/mL) compared with free DOX (2.36-6.025 μg/mL). In vivo results suggested that the selected proportions of chitosan-BSA created nonhemolytic and biocompatible stable NPs at the selected dose of 20 mg/kg. Despite the different formulations, this study demonstrated that these NPs could serve as safe drug carriers in further in vivo investigations.

Protein-polysaccharide nanohybrids: Hybridization techniques and drug delivery applications

Complex nanosystems fabricated by hybridization of different types of materials such as lipids, proteins, or polysaccharides are usually superior to simple ones in terms of features and applications. Proteins and polysaccharides hold great potential for development of nanocarriers for drug delivery purposes based on their unique biocompatibility, biodegradability, ease of functionalization, improved biodistribution and minimal toxicity profiles. Protein-polysaccharide nanohybrids have gained a lot of attention in the past few years particularly for drug delivery applications. In this review, different hybridization techniques utilized in the fabrication of such nanohybrids including electrostatic complexation, Maillard conjugation, chemical coupling and electrospinning were thoroughly reviewed. Moreover, various formulation factors affecting the characteristics of the formed nanohybrids were discussed. We also reviewed in depth the outcomes of such hybridization ranging from stability enhancement, to toxicity reduction, improved biocompatibility, and drug release modulation. We also gave an insight on their limitations and what hinders their clinical translation and market introduction.

Efficient gene delivery by oligochitosan conjugated serum albumin: Facile synthesis, polyplex stability, and transfection

Chitosan and its derivatives have shown to be potential gene carriers with biocompatiblility and safety. However, their practical delivery is far from being ideal because of the low transfection efficiency. The present work describes the potential of a natural protein, bovine serum albumin (BSA), conjugated with a natural oligosaccharide, oligochitosan (OC), as a considerable promising approach for a safe and efficient non-viral gene delivery vector. The FTIR spectra proved the effective conjugation of BSA with OC through covalent bond. The condensation ability of plasmid DNA (pDNA) with a BSA-OC biopolymer was analyzed by gel retardation assay, competition binding assay, and dynamic light scattering used to measure the nanoparticle size. In addition, the BSA-OC biopolymer showed the protection of pDNA from enzymatic degradation by DNase I and showed good stability when exposed to 50% fetal bovine serum. The transfection efficiency was evaluated in the presence of 10% serum-supplemented media or serum-free media on three kinds of mammalian cells. Our results showed that the BSA-OC biopolymer is a good non-viral vehicle for gene delivery. We investigated the parameters such as the pDNA payload, temperature, incubating duration, and biopolymer/pDNA ratio on the transfection efficiency. This hybrid vehicle had the ability to transfect 90% of cells and to maintain 80% of cell viability. The aforementioned results suggest that the facile synthesis of the BSA-OC biopolymer could overcome the cytotoxicity problem and transfection barriers during in vitro gene delivery.

Development of Albumin Coupled, Cholesterol Stabilized, Lipid Nanoemulsion of Methotrexate, and TNF-α Inhibitor for Improved In Vivo Efficacy Against Rheumatoid Arthritis

Methotrexate (MTX; an anti-folate) and etanercept (ET; a TNF-α inhibitor) are used against arthritis; however, limitations like short biological half-life, low cutaneous absorption, and acidic instability limit their clinical relevance. Therefore, the aim of the investigation was to develop albumin coupled lipid nanoemulsion of MTX and ET for improved efficacy by virtue of their controlled release and specificity at the arthritic site. This emulsion was prepared by high-speed homogenization and stabilized using cholesterol. Lipid nanoemulsion of MTX and ET (MTX+ET-LNE) was coupled with albumin (MTX+ET-ALNE). MTX+ET-ALNE was characterized on the basis of particle size (410 ± 25.4 nm), PDI (0.160), and zeta potential (+38.6 ± 5.6 mV) and evaluated for pH (6.15), drug content (97.7 ± 2.17%), entrapment efficiency (76 ± 4.6%), in vitro release, and in vitro cytotoxicity. About 82.6 ± 9.60% release of MTX+ET was observed in 24 h from the developed MTX+ET-ALNE which may help maintain therapeutic level of drugs in blood at least for one day. No toxicity was observed when Raw 264.7 cells were treated with MTX+ET-ALNE, and no causalities of mice were observed at experimental in vivo dose (10 mg/kg BW) of MTX+ET in MTX+ET-ALNE-treated group. MTX+ET-ALNE treatment has alleviated arthritic scores and inflammatory cytokines level in a very significant manner when compared with MTX+ET-LNE and MTX+ET solutions. MTX+ET-ALNE-treated group restored histological alterations (cartilage/bone erosion, inflammatory cell infiltration, synovial hyperplasia, and narrower joint space) as observed in diseased treated groups. In conclusion, MTX+ET-ALNE can be opted as efficacious and clinically pertinent option to the current medication systems of arthritis.

Recent Advances in Nanomaterials for Gene Delivery-A Review

With the rapid development of nanotechnology in the recent decade, novel DNA and RNA delivery systems for gene therapy have become available that can be used instead of viral vectors. These non-viral vectors can be made of a variety of materials, including inorganic nanoparticles, carbon nanotubes, liposomes, protein and peptide-based nanoparticles, as well as nanoscale polymeric materials. They have as advantages over viral vectors a decreased immune response, and additionally offer flexibility in design, allowing them to be functionalized and targeted to specific sites in a biological system with low cytotoxicity. The focus of this review is to provide an overview of novel nanotechnology-based methods to deliver DNA and small interfering RNAs into biological systems.

Albumin nanostructures as advanced drug delivery systems

INTRODUCTION

One of the biggest impacts that the nanotechnology has made on medicine and biology, has been in the area of drug delivery systems (DDSs). Many drugs suffer from serious problems concerning insolubility, instability in biological environments, poor uptake into cells and tissues, sub-optimal selectivity for targets and unwanted side effects. Nanocarriers can be designed as DDSs to overcome many of these drawbacks. One of the most versatile building blocks to prepare these nanocarriers is the ubiquitous, readily available and inexpensive protein, serum albumin. Areas covered: This review covers the use of different types of albumin (human, bovine, rat, and chicken egg) to prepare nanoparticle and microparticle-based structures to bind drugs. Various methods have been used to modify the albumin structure. A range of targeting ligands can be attached to the albumin that can be recognized by specific cell receptors that are expressed on target cells or tissues. Expert opinion: The particular advantages of albumin used in DDSs include ready availability, ease of chemical modification, good biocompatibility, and low immunogenicity. The regulatory approvals that have been received for several albumin-based therapeutic agents suggest that this approach will continue to be successfully explored.

Temperature-Responsive Smart Nanocarriers for Delivery Of Therapeutic Agents: Applications and Recent Advances

Smart drug delivery systems (DDSs) have attracted the attention of many scientists, as carriers that can be stimulated by changes in environmental parameters such as temperature, pH, light, electromagnetic fields, mechanical forces, etc. These smart nanocarriers can release their cargo on demand when their target is reached and the stimulus is applied. Using the techniques of nanotechnology, these nanocarriers can be tailored to be target-specific, and exhibit delayed or controlled release of drugs. Temperature-responsive nanocarriers are one of most important groups of smart nanoparticles (NPs) that have been investigated during the past decades. Temperature can either act as an external stimulus when heat is applied from the outside, or can be internal when pathological lesions have a naturally elevated termperature. A low critical solution temperature (LCST) is a special feature of some polymeric materials, and most of the temperature-responsive nanocarriers have been designed based on this feature. In this review, we attempt to summarize recent efforts to prepare innovative temperature-responsive nanocarriers and discuss their novel applications.

Microfluidic systems for stem cell-based neural tissue engineering

Neural tissue engineering aims at developing novel approaches for the treatment of diseases of the nervous system, by providing a permissive environment for the growth and differentiation of neural cells. Three-dimensional (3D) cell culture systems provide a closer biomimetic environment, and promote better cell differentiation and improved cell function, than could be achieved by conventional two-dimensional (2D) culture systems. With the recent advances in the discovery and introduction of different types of stem cells for tissue engineering, microfluidic platforms have provided an improved microenvironment for the 3D-culture of stem cells. Microfluidic systems can provide more precise control over the spatiotemporal distribution of chemical and physical cues at the cellular level compared to traditional systems. Various microsystems have been designed and fabricated for the purpose of neural tissue engineering. Enhanced neural migration and differentiation, and monitoring of these processes, as well as understanding the behavior of stem cells and their microenvironment have been obtained through application of different microfluidic-based stem cell culture and tissue engineering techniques. As the technology advances it may be possible to construct a "brain-on-a-chip". In this review, we describe the basics of stem cells and tissue engineering as well as microfluidics-based tissue engineering approaches. We review recent testing of various microfluidic approaches for stem cell-based neural tissue engineering.

Nanoparticle-based targeted gene therapy for lung cancer

Despite striking insights on lung cancer progression, and cutting-edge therapeutic approaches the survival of patients with lung cancer, remains poor. In recent years, targeted gene therapy with nanoparticles is one of the most rapidly evolving and extensive areas of research for lung cancer. The major goal of targeted gene therapy is to bring forward a safe and efficient treatment to cancer patients via specifically targeting and deterring cancer cells in the body. To achieve high therapeutic efficacy of gene delivery, various carriers have been engineered and developed to provide protection to the genetic materials and efficient delivery to targeted cancer cells. Nanoparticles play an important role in the area of drug delivery and have been widely applied in cancer treatments for the purposes of controlled release and cancer cell targeting. Nanoparticles composed of artificial polymers, proteins, polysaccharides and lipids have been developed for the delivery of therapeutic deoxyribonucleic acid (DNA) or ribonucleic acid (RNA) sequences to target cancer. In addition, the effectiveness of cancer targeting has been enhanced by surface modification or conjugation with biomolecules on the surface of nanoparticles. In this review article we provide an overview on the latest developments in nanoparticle-based targeted gene therapy for lung cancers. Firstly, we outline the conventional therapies and discuss strategies for targeted gene therapy using nanoparticles. Secondly, we provide the most representative and recent researches in lung cancers including malignant pleural mesothelioma, mainly focusing on the application of Polymeric, Lipid-based, and Metal-based nanoparticles. Finally, we discuss current achievements and future challenges.

Chitosan/Sterculia striata polysaccharides nanocomplex as a potential chloroquine drug release device

Nanoparticles are produced by means of polyelectrolyte complexation (PEC) of oppositely charged polycationic chitosan (CH) with polyanionic polysaccharide extracted from Sterculia striata exudates (rhamnogalacturonoglycan (RG)-type polysaccharide). The nanoparticles formed with low-molar-mass CH are larger than those formed with high-molar-mass CH. This behavior is in contrast with that previously observed for other systems and may be attributed to different mechanisms related to the association of CH with RG of higher persistence length chain than that of CH. Nanoparticles harnessed with a charge ratio (n(+)/n(-)) of <1 are smaller than particles with an excess of polycations. Particles with hydrodynamic sizes smaller than 100nm are achieved using a polyelectrolyte concentration of 10(-4)gmL(-1) and charge ratio (n(+)/n(-)) of <1. The CH/RG nanoparticles are associated with chloroquine (CQ) with an efficiency of 28% and release it for up to ∼60% within ∼10h, whereas in the latter, only ∼40% of the CQ was released after 24h. The main factor that influenced drug release rate is the nanoparticle charge ratio.

Smart micro/nanoparticles in stimulus-responsive drug/gene delivery systems

New achievements in the realm of nanoscience and innovative techniques of nanomedicine have moved micro/nanoparticles (MNPs) to the point of becoming actually useful for practical applications in the near future. Various differences between the extracellular and intracellular environments of cancerous and normal cells and the particular characteristics of tumors such as physicochemical properties, neovasculature, elasticity, surface electrical charge, and pH have motivated the design and fabrication of inventive "smart" MNPs for stimulus-responsive controlled drug release. These novel MNPs can be tailored to be responsive to pH variations, redox potential, enzymatic activation, thermal gradients, magnetic fields, light, and ultrasound (US), or can even be responsive to dual or multi-combinations of different stimuli. This unparalleled capability has increased their importance as site-specific controlled drug delivery systems (DDSs) and has encouraged their rapid development in recent years. An in-depth understanding of the underlying mechanisms of these DDS approaches is expected to further contribute to this groundbreaking field of nanomedicine. Smart nanocarriers in the form of MNPs that can be triggered by internal or external stimulus are summarized and discussed in the present review, including pH-sensitive peptides and polymers, redox-responsive micelles and nanogels, thermo- or magnetic-responsive nanoparticles (NPs), mechanical- or electrical-responsive MNPs, light or ultrasound-sensitive particles, and multi-responsive MNPs including dual stimuli-sensitive nanosheets of graphene. This review highlights the recent advances of smart MNPs categorized according to their activation stimulus (physical, chemical, or biological) and looks forward to future pharmaceutical applications.

Nanotechnology for photodynamic therapy: a perspective from the Laboratory of Dr. Michael R. Hamblin in the Wellman Center for Photomedicine at Massachusetts General Hospital and Harvard Medical School

The research interests of the Hamblin Laboratory are broadly centered on the use of different kinds of light to treat many different diseases. Photodynamic therapy (PDT) uses the combination of dyes with visible light to produce reactive oxygen species and kill bacteria, cancer cells and destroy unwanted tissue. Likewise, UV light is also good at killing especially pathogens. By contrast, red or near-infrared light can have the opposite effect, to act to preserve tissue from dying and can stimulate healing and regeneration. In all these applications, nanotechnology is having an ever-growing impact. In PDT, self-assembled nano-drug carriers (micelles, liposomes, etc.) play a great role in solubilizing the photosensitizers, metal nanoparticles can carry out plasmon resonance enhancement, and fullerenes can act as photosensitizers, themselves. In the realm of healing, single-walled carbon nanotubes can be electrofocused to produce nano-electonic biomedical devices, and nanomaterials will play a great role in restorative dentistry.

Carbon nanotubes part I: preparation of a novel and versatile drug-delivery vehicle

INTRODUCTION

It is 23 years since carbon allotrope known as carbon nanotubes (CNT) was discovered by Iijima, who described them as "rolled graphite sheets inserted into each other". Since then, CNTs have been studied in nanoelectronic devices. However, CNTs also possess the versatility to act as drug- and gene-delivery vehicles.

AREAS COVERED

This review covers the synthesis, purification and functionalization of CNTs. Arc discharge, laser ablation and chemical vapor deposition are the principle synthesis methods. Non-covalent functionalization relies on attachment of biomolecules by coating the CNT with surfactants, synthetic polymers and biopolymers. Covalent functionalization often involves the initial introduction of carboxylic acids or amine groups, diazonium addition, 1,3-dipolar cycloaddition or reductive alkylation. The aim is to produce functional groups to attach the active cargo.

EXPERT OPINION

In this review, the feasibility of CNT being used as a drug-delivery vehicle is explored. The molecular composition of CNT is extremely hydrophobic and highly aggregation-prone. Therefore, most of the efforts towards drug delivery has centered on chemical functionalization, which is usually divided in two categories; non-covalent and covalent. The biomedical applications of CNT are growing apace, and new drug-delivery technologies play a major role in these efforts.