Preparation and optimization of ciprofloxacin encapsulated niosomes: A new approach for enhanced antibacterial activity, biofilm inhibition and reduced antibiotic resistance in ciprofloxacin-resistant methicillin-resistance Staphylococcus aureus.

Ciprofloxacin is an alternative to vancomycin for treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. The objective of this study was to optimization of niosomes encapsulated ciprofloxacin and evaluate their antibacterial and anti-biofilm efficacies against ciprofloxacin-resistant methicillin-resistant S. aureus (CR-MRSA) strains. Formulation of niosomes encapsulated ciprofloxacin were optimized by changing the proportions of Tween 60, Span 60, and cholesterol. The optimized ciprofloxacin encapsulated niosomal formulations based on Span 60 and Tween 60 were prepared and characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS). The SEM and TEM results showed that the formulation of niosomes encapsulated ciprofloxacin were spherical with a size between 50 and 150 nm. The prepared niosomal formulations showed high storage stability up to 30 days with the slight change in size and drug entrapment during the storage, making them good candidates for drug delivery systems. Optimum niosome encapsulated ciprofloxacin enhanced antibacterial activity against CR-MRSA strains via reduction in minimum inhibitory concentration (MIC) value and inhibited significantly biofilm formation. Niosome encapsulated ciprofloxacin down-regulated the expression of icaB biofilm formation gene. Our results showed that encapsulating ciprofloxacin in niosomes is a promising approach to enhanced antibacterial activity, biofilm inhibition and reduced resistance to antibiotic in CR-MRSA strains.

Encapsulation of Thymol in Gelatin Methacryloyl (GelMa)-Based Nanoniosome Enables Enhanced Antibiofilm Activity and Wound Healing.

Non-healing wounds impose huge cost on patients, healthcare, and society, which are further fortified by biofilm formation and antimicrobial resistance (AMR) problems. Here, Thymol, an herbal antimicrobial agent, is utilized to combat AMR. For efficient delivery of Thymol gelatin methacryloyl (GelMa), a hydrophilic polymeric hydrogel with excellent biocompatibility combined with niosome was used to encapsulate Thymol. After optimization of the niosomal Thymol (Nio-Thymol) in the company of GelMa (Nio-Thymol@GelMa) to achieve maximum entrapment efficiency, minimum size, and low polydispersity index, the Thymol release peaked at 60% and 42% from Nio-Thymol@GelMa in medium with pH values of 6.5 and 7.4 after 72 h, respectively. Furthermore, Nio-Thymol@GelMa demonstrated higher antibacterial and anti-biofilm activity than Nio-Thymol and free Thymol against both Gram-negative and Gram-positive bacteria. Interestingly, compared with other obtained formulations, Nio-Thymol@GelMa also led to greater enhancement of migration of human dermal fibroblasts in vitro, and higher upregulation of the expression of certain growth factors such as FGF-1, and matrix metalloproteinases such as MMP-2 and MMP-13. These results suggest that Nio-Thymol@GelMa can represent a potential drug preparation for Thymol to enhance the wound healing process and antibacterial efficacy.

Niosomes: a novel targeted drug delivery system for cancer.

Recently, nanotechnology is involved in various fields of science, of which medicine is one of the most obvious. The use of nanoparticles in the process of treating and diagnosing diseases has created a novel way of therapeutic strategies with effective mechanisms of action. Also, due to the remarkable progress of personalized medicine, the effort is to reduce the side effects of treatment paths as much as possible and to provide targeted treatments. Therefore, the targeted delivery of drugs is important in different diseases, especially in patients who receive combined drugs, because the delivery of different drug structures requires different systems so that there is no change in the drug and its effectiveness. Niosomes are polymeric nanoparticles that show favorable characteristics in drug delivery. In addition to biocompatibility and high absorption, these nanoparticles also provide the possibility of reducing the drug dosage and targeting the release of drugs, as well as the delivery of both hydrophilic and lipophilic drugs by Niosome vesicles. Since various factors such as components, preparation, and optimization methods are effective in the size and formation of niosomal structures, in this review, the characteristics related to niosome vesicles were first examined and then the in silico tools for designing, prediction, and optimization were explained. Finally, anticancer drugs delivered by niosomes were compared and discussed to be a suitable model for designing therapeutic strategies. In this research, it has been tried to examine all the aspects required for drug delivery engineering using niosomes and finally, by presenting clinical examples of the use of these nanocarriers in cancer, its clinical characteristics were also expressed.

Preparation, Optimization and In-Vitro Evaluation of Curcumin-Loaded Niosome@calcium Alginate Nanocarrier as a New Approach for Breast Cancer Treatment.

Cancer is one of the most common causes of mortality, and its various treatment methods can have many challenges for patients. As one of the most widely used cancer treatments, chemotherapy may result in diverse side effects. The lack of targeted drug delivery to tumor tissues can raise the possibility of damage to healthy tissues, with attendant dysfunction. In the present study, an optimum formulation of curcumin-loaded niosomes with a calcium alginate shell (AL-NioC) was developed and optimized by a three-level Box-Behnken design-in terms of dimension and drug loading efficiency. The niosomes were characterized by transmission electron microscopy, Fourier-transform infrared spectroscopy, and dynamic light scattering. The as-formulated niosomes showed excellent stability for up to 1 month at 4 °C. Additionally, the niosomal formulation demonstrated a pH-dependent release; a slow-release profile in physiological pH (7.4), and a more significant release rate at acidic conditions (pH = 3). Cytotoxicity studies showed high compatibility of AL-NioC toward normal MCF10A cells, while significant toxicity was observed in MDA-MB-231 and SKBR3 breast cancer cells. Gene expression studies of the cancer cells showed downregulation of Bcl2, cyclin D, and cyclin E genes, as well as upregulation of P53, Bax, caspase-3, and caspase-9 genes expression following the designed treatment. Flow cytometry studies confirmed a significant enhancement in the apoptosis rate in the presence of AL-NioC in both MDA-MB-231 and SKBR3 cells as compared to other samples. In general, the results of this study demonstrated that-thanks to its biocompatibility toward normal cells-the AL-NioC formulation can efficiently deliver hydrophobic drugs to target cancer cells while reducing side effects.

Niosome-encapsulated tobramycin reduced antibiotic resistance and enhanced antibacterial activity against multidrug-resistant clinical strains of Pseudomonas aeruginosa.

In the current study, niosome-encapsulated tobramycin based on Span 60 and Tween 60 was synthesized and its biological efficacies including anti-bacterial, anti-efflux, and anti-biofilm activities were investigated against multidrug resistant (MDR) clinical strains of Pseudomonas aeruginosa. The niosomal formulations were characterized using scanning electron microscopy, transmission electron microscopy, and dynamic light scattering measurement. The encapsulation efficiency was found to be 69.54% ±; 0.67. The prepared niosomal formulations had a high storage stability to 60 days with small changes in size and drug entrapment, which indicates that it is a suitable candidate for pharmaceutical applications. The results of biological study showed the anti-bacterial activity via reduction of antibiotic resistance, enhanced anti-efflux and anti-biofilm activities by more folds in comparison to free tobramycin. In addition, niosome encapsulated tobramycin down-regulated the MexAB-OprM efflux genes, pslA and pelA biofilm related genes in MDR P. aeruginosa strains. The anti-proliferative activity of formulation was evaluated against HEK293 cell lines, which exhibited negligible cytotoxicity against HEK293 cells. The finding of our study shows that encapsulation of tobramycin in niosome enhanced the antibacterial activity and reduced antibiotic resistance in MDR strains of P. aeruginosa comparing to free tobramycin and it can be considered as a favorable drug delivery system.

Enhanced Antibacterial Activity of Echinacea angustifolia Extract against Multidrug-Resistant Klebsiella pneumoniae through Niosome Encapsulation.

With the increased occurrence of antibiotic-resistant bacteria, alternatives to classical antibiotics are urgently needed for treatment of various infectious diseases. Medicinal plant extracts are among the promising candidates due to their bioactive components. The aim of this study was to prepare niosome-encapsulated Echinacea angustifolia extract and study its efficacy against multidrug-resistant Klebsiella pneumoniae strains. Encapsulation was first optimized by Design of Experiments, followed by the empirical study. The obtained niosomes were further characterized for the size and morphology using dynamic light scattering (DLS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Spherical niosomes had a diameter of 142.3 ± 5.1 nm, as measured by DLS. The entrapment efficiency (EE%) of E. angustifolia extract reached up to 77.1% ± 0.3%. The prepared niosomes showed a controlled drug release within the tested 72 h and a storage stability of at least 2 months at both 4 and 25 °C. The encapsulated E. angustifolia displayed up to 16-fold higher antibacterial activity against multidrug-resistant K.pneumoniae strains, compared to the free extract. Additionally, the niosome exhibited negligible cytotoxicity against human foreskin fibroblasts. We anticipate that the results presented herein could contribute to the preparation of other plant extracts with improved stability and antibacterial activity, and will help reduce the overuse of antibiotics by controlled release of natural-derived drugs.