Introduction: Dextran is a family of natural polysaccharides that is widely under investigation for use as polymeric carriers in novel drug delivery systems. The optimal drug delivery (and consequently maximum therapeutic effect) will be accomplished when carrier systems are used mainly for drugs with antitumoral activity, as they increase their blood permanence time, taking advantage of the increased mass that reduces kidney ultrafiltration. Areas covered: This review summarizes the attempts that have been made in the development of dextran conjugates and their application. The manuscript describes dextran hydrogels, the use of conjugates of dextran in bioadhesive oral delivery systems, colon drug delivery, reduction of ulcerogenicity of drugs, production of micelles, solubilization, long-circulating pharmaceutical carriers as anticancer drug carriers, non-viral vectors, stabilization of enzymes, functionalization of nanomaterials, diagnosis of solid tumors and hyperthermic treatment and liver targeting. Expert opinion: Dextran conjugation has aided the design of new tailor-made polymers with different molecular weights, shapes, structures and with the functional groups needed for coupling at the desired positions in the chain. Dextran prodrugs are very useful systems for achieving controlled drug release and drug targeting. In particular, various dextran-antitumor drug conjugates enhance the effectiveness and improve the cytotoxic effects of chemotherapeutic agents. Future studies should concentrate on barriers for their clinical use and safety as a drug carrier.

The aim of this study was to develop novel biomedicated nanofiber electrospun mats for controlled drug release, especially drug release directly to an injury site to accelerate wound healing. Nanofibers of poly(vinyl alcohol) (PVA), poly(vinyl acetate) (PVAc), and a 50:50 composite blend, loaded with ciprofloxacin HCl (CipHCl), were successfully prepared by an electrospinning technique for the first time. The morphology and average diameter of the electrospun nanofibers were investigated by scanning electron microscopy. X-ray diffraction studies indicated an amorphous distribution of the drug inside the nanofiber blend. Introducing the drug into polymeric solutions significantly decreased solution viscosities as well as nanofiber diameter. In vitro drug release evaluations showed that both the kind of polymer and the amount of drug loaded greatly affected the degree of swelling, weight loss, and initial burst and rate of drug release. Blending PVA and PVAc exhibited a useful and convenient method for electrospinning in order to control the rate and period of drug release in wound healing applications. Also, the thickness of the blend nanofiber mats strongly influenced the initial release and rate of drug release.

Purpose: Ferulic acid (FA) is a poorly water-soluble natural antioxidant with anticancer activity. This poor solubility limits the application of FA in the food and pharmaceutical industry. Cyclodextrin nanosponges (CD-NSs) are a novel group of cross-linked CD derivatives which can be used to enhance the solubility of low-soluble bioactive compounds. Methods: In this study, FA was encapsulated into the NSs in the proportion of 1:4 (FA:NS). Diphenyl carbonate was used as a cross-linker in different proportions with β-CD. Characterization of obtained NSs was performed using scanning electron microscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) analysis. Results: Our results revealed that the solubility of encapsulated FA was increased up to fifteenfold compared with pure FA in the proportion of 1:4 (CD:cross-linker). The results of FTIR, XRD, and DSC confirmed the interaction of FA with NSs. The cytotoxicity of encapsulated FA against MCF7 and 4T1 breast cancer cell lines was investigated using different concentrations of FA in 24, 48, and 72 hrs. The cytotoxicity assay indicated that FA treatment reduced viability and enhanced apoptosis of cancer cells. IC50 value of encapsulated FA (250 ppm) was decreased by threefold when compared with pure FA (750 ppm). Conclusion: In general, CD-NS was found to be a suitable delivery system for poorly soluble bioactives such as FA.

Rheumatoid arthritis (RA) is a chronic inflammatory disease with complex pathology characterized by inflammation of joints, devastation of the synovium, pannus formation, bones and cartilage destruction and often is associated with persistent arthritic pain, swelling, stiffness and work disability. In conventional RA therapy, because of short biological half-life, poor bioavailability, high and frequent dosing is required. Thereby, these anti-RA medications, which unable to selectively target affected zone, may cause severe side effects in extra-articular tissues. Today, nanotechnology has emerged as promising tool in the development of novel drug delivery systems for the treatment and diagnosis of intractable diseases such as RA. Active targeting in RA nanomedicine has also been introduced a successful way for facilitating specific uptake of therapeutic agents by the disease cells. In this review, it is attempted to describe various targeted drug delivery systems (localized and receptor-based) used for RA diagnosis and therapy. Then, we highlight recent developments related to various non-viral gene delivery systems for RA gene therapy

Solid lipid nanoparticles (SLNs) have been studied as a drug-delivery system for the controlling of drug release. These colloidal systems have many important advantages, such as biocompatibility, good tolerability, and ease of scale-up. In the preparation of SLNs, many factors are involved in the characteristics of the particles, such as particle size, drug loading, and zeta potential. In this study, fractional factorial design was applied to examine which variables affect the physicochemical properties of amikacin SLNs. Study was continued by a statistical central composite design (CCD) to minimize particle size and maximize drug-loading efficiency of particles. The results showed that three quantitative factors, including the amount of lipid phase, ratio of drug to lipid, and volume of aqueous phase, were the most important variables on studied responses. The best predicted model for particle size was the quadratic model, and for drug-loading efficiency, was the linear model without any significant lack of fit. Optimum condition was achieved when the ratio of drug to lipid was set at 0.5, the amount of lipid phase at 314 mg, and the volume of aqueous phase at 229 mL. The optimized particle size was 149 ± 4 nm and the drug-loading efficiency 88 ± 5%. Polydispersity index was less than 0.3. The prepared particles had spherical shape, and the drug release from nanoparticles continued for 144 hours (6 days) without significant burst effect.

Background: Niosomes are non-ionic surfactant vesicles used as drug carriers for encapsulating both hydrophobic and hydrophilic drugs. The aim of this study is to evaluate the effect of different surfactants on the physical properties and stability of carvedilol niosomes designed to improve oral bioavailability. Materials and Methods: Different niosomal formulations were prepared using a film hydration method, with various mixtures of different non-ionic surfactants including Span 20, 40, and 60, and also Tween 20, 40, and 60, along with cholesterol. The physicochemical characteristics of the formulations were evaluated in vitro. Results: The drug encapsulation efficiency was reduced by using lauryl (C₁₂) chain containing surfactants, that is, Span/Tween. Cholesterol content and drug entrapment were the main factors affecting the mean particle size of the niosomes. The drug release profiles from most of the formulations were fitted well with the Baker-Lonsdale model, indicating a diffusion-based drug release mechanism. Niosomes prepared from 50 and 40% of the cholesterol with 25 or 30% of Span/Tween 60 showed the highest stability due to their high transition temperature and solid state feature of these surfactants. Conclusions: From the results obtained, it may be concluded that nanoniosomes are promising stable carriers for the oral delivery of carvedilol.