Electrospun nanofibers: building blocks for the repair of bone tissue.

Bone, one of the hardest structures of the body, is the basic constituent of the skeletal system, which gives the shape to the body, provides mechanical support for muscles and soft tissues, and provides movement. Even if there is no damage, bone remodeling is a permanent process to preserve and renew the structural, biochemical, and biomechanical integrity of bone tissue. Apart from the remodeling, bone healing is the highly complicated process of repairing deficiencies of bone tissue by the harmonious operation of osteoblasts, osteocytes, osteoclasts, and bone lining cells. Various materials can be used to both trigger the bone healing process and to provide mechanical support to damaged bone. Nanofiber scaffolds are at the forefront of these types of systems because of their extremely large surface area-to-volume ratio, small pore size, and high porosity. Nanofibers are known to be highly functional systems with the ability to mimic the structure and function of the natural bone matrix, facilitating osteogenesis for cell proliferation and bone regeneration. Electrospinning is an easy and fast method to produce non-woven structures consisting of continuous ultrafine fibers with diameters ranging from micrometers down to nanometers. The simplicity and cost-effectiveness of the electrospinning technique, its ability to use a wide variety of synthetic, natural, and mixed polymers, and the formation of highly porous and continuous fibers are the remarkable features of this method. The importance of nanofiber-based scaffolds in bone tissue regeneration is increasing because of suitable pore size, high porosity, osteoinduction, induction of bone growth with osteoconduction, adaptability to the target area, biodegradation, and appropriate mechanical properties, which are among the main parameters that are important in the design of polymeric bone grafts. The aim of this review is to cast light on the increasing use of nanofiber-based scaffolds in bone tissue regeneration and give an insight about bone regeneration, production techniques of the electrospun nanofibers, and varying formulation parameters in order to reach different drug delivery goals. This review also provides an extensive market research of electrospun nanofibers and an overview on scientific research and patents in the field.

Bacterial Membrane Vesicles as Smart Drug Delivery and Carrier Systems: A New Nanosystems Tool for Current Anticancer and Antimicrobial Therapy.

Bacterial membrane vesicles (BMVs) are known to be critical communication tools in several pathophysiological processes between bacteria and host cells. Given this situation, BMVs for transporting and delivering exogenous therapeutic cargoes have been inspiring as promising platforms for developing smart drug delivery systems (SDDSs). In the first section of this review paper, starting with an introduction to pharmaceutical technology and nanotechnology, we delve into the design and classification of SDDSs. We discuss the characteristics of BMVs including their size, shape, charge, effective production and purification techniques, and the different methods used for cargo loading and drug encapsulation. We also shed light on the drug release mechanism, the design of BMVs as smart carriers, and recent remarkable findings on the potential of BMVs for anticancer and antimicrobial therapy. Furthermore, this review covers the safety of BMVs and the challenges that need to be overcome for clinical use. Finally, we discuss the recent advancements and prospects for BMVs as SDDSs and highlight their potential in revolutionizing the fields of nanomedicine and drug delivery. In conclusion, this review paper aims to provide a comprehensive overview of the state-of-the-art field of BMVs as SDDSs, encompassing their design, composition, fabrication, purification, and characterization, as well as the various strategies used for targeted delivery. Considering this information, the aim of this review is to provide researchers in the field with a comprehensive understanding of the current state of BMVs as SDDSs, enabling them to identify critical gaps and formulate new hypotheses to accelerate the progress of the field.

Development of salting-out extraction methodology for the determination of piroxicam from polymeric based nanocarriers and biological samples.

The aim of the present study is to develop the polymeric nanoparticulate drug delivery systems of piroxicam and to evaluate the in-vitro characteristics such as entrapment efficiency, surface morphology, in-vitro drug release performance, etc. For this reason, a novel HPLC methodology was developed for the determination of piroxicam from its bulk form, pharmaceutical preparation, and nanoparticulate delivery systems. Furthermore, the developed formulation was applied to the rats and the biological samples (plasma, liver, heart, spleen, kidney, and lung homogenates) were analyzed by the developed HPLC method following a salting-out assisted liquid-liquid extraction strategy for the first time in the literature. A Kinetex C18 analytical column (150 mm × 4.6 mm i.d., 5 µm) was used as a stationary phase with a 0.8 mL/min flow rate of acetonitrile: phosphate buffer (40:60, v/v), the column oven was adjusted to 40 °C and detection wavelength is set to 360 nm. Developed method were validated as per selectivity, linearity, LOD, LOQ, precision, and accuracy specified in the International Council for Harmonisation guidelines. As a result of the present study, it has been shown that the analysis of piroxicam from the bulk form, pharmaceutical preparation, developed polymeric-based drug delivery system, and biological samples can be successfully performed and no interferences were observed in any matrix. The developed method was also successfully utilized to study the tissue distribution of piroxicam in rats.

Box-Behnken design optimization and in vitro cell based evaluation of piroxicam loaded core-shell type hybrid nanocarriers for prostate cancer.

In the present research, piroxicam entrapped core-shell lipid-polymer hybrid nanocarriers were developed and also evaluated in terms of nanoparticle features and cell-based in vitro efficacy on prostate cancer cells. Box-Behnken optimization approach was implemented to evaluate the impact of the input variables, namely phospholipid/PLGA ratio, total lipids/lecithin molar ratio, and piroxicam concentration, on two output variables: particle size and entrapment efficiency. Surface charge, size distribution, morphological structure of particles, drug release profiles, presence of outer lipid shell, thermal profile and possible interactions and storage stability of core-shell nanocarriers of piroxicam were studied as particle features. Cell viability, apoptosis and cell cycle arrest studies were utilized for in vitro cell-based evaluation of the core-shell nanosystems. The hybrid nanocarrier formulation with a particle size of 119.2 nm and an entrapment efficiency of 91.7% at the center point of the design was selected as the optimized formulation according to the desired function (d) method applied within the scope of the Box-Behnken design approach and RSM strategy. The cell viability and apoptosis experiments were performed on the optimized nanocarrier. In conclusion, this study demonstrates that the optimized core-shell nanoformulation of piroxicam is a more promising strategy in the treatment of prostate cancer compared to the pure molecule.

Clinicopathological and immunohistochemical evaluation of lonidamine-entrapped lipid-polymer hybrid nanoparticles in treatment of benign prostatic hyperplasia: An experimental rat model.

Benign prostatic hyperplasia (BPH) is a progressive proliferative disease, the incidence of which is constantly increasing due to aging of population. In this research, a hexokinase-II enzyme inhibiting agent, lonidamine - the use of which is limited in BPH treatment due to high hepatic toxicity observed after three months of treatment - was selected as an active agent, based on its mechanism of action in treating BPH. The aim of this study was to evaluate in vivo therapeutic efficacy and hepatic toxicity of lipid-polymer hybrid nanoparticles of lonidamine in a rat BPH model created in rat prostates. After local injections of hybrid nanoparticles of lonidamine were administered to the rat prostates, hyperplasic structures of prostates were evaluated in terms of prostatic index values, immunohistochemical evaluations, and histopathological findings. Liver blood enzyme values were also determined to specify hepatic toxicity. Apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) reaction and histopathological methods to determine intravital degenerative destruction in liver. Through this study, lonidamine-loaded hybrid nanoparticles were found to reduce the hepatic toxicity and increase therapeutic efficiency of lonidamine. Therefore, lonidamine-entrapped hybrid nanoparticles may provide a promising, and very safe, drug delivery strategy in the treatment of BPH.

Development and Statistical Optimization of Solid Lipid Nanoparticle Formulations of Fluticasone Propionate.

OBJECTIVES: The aim of this study was to develop fluticasone propionate (FP)-loaded solid lipid nanoparticle (SLN) formulations by using factorial design approach. MATERIALS AND METHODS: Tristearin percentages (X1) (1%, 2%, and 4%) and homogenization cycles (X2) (2, 4, and 8 cycles) were selected as independent variables in the factorial design. SLN formulations were optimized by multiple linear regression (MLR) to evaluate the influence of the selected process and formulation independent variables on SLNs' characteristics, namely as encapsulation efficiency (Q1) and particle size (Q2). The polydispersity index and surface charge of the SLNs were also evaluated in this research. Moreover, transmission electron microscopy, differential scanning calorimetry, and in vitro drug release studies were carried out on the optimum SLN formulation. RESULTS: The MLR analysis indicated that as the homogenization cycle (X2) increased in the production process, the mean particle size decreased. CONCLUSION: This research showed that FP-encapsulated SLNs with desired characteristics can be produced by varying the production and content variables of the formulations.

Encapsulation of cucurbitacin B into lipid polymer hybrid nanocarriers induced apoptosis of MDAMB231 cells through PARP cleavage.

In the present study, we developed the lipid polymer hybrid nanoparticles of cucurbitacin B (CuB) and evaluated its effects on triple negative breast cancer cells. The 32 factorial design was utilized to understand the influence of input variables including PEG-conjugated phospholipid/biodegradable polymer ratio and the total lipids/lecithin molar percentage ratio. The hybrid formulation at the center point of design was specified as optimal hybrid nanocarrier due to its superior features. CuB loaded nanoparticles (CuB-NP) inhibited cell growth through a cell cycle arrest at G0/G1 phase. The studies investigating the efficacy of CuB-NP on apoptosis of cancer cells showed that the annexin v-bound cell population was 20.66 ± 1.99%, and the depolarized cell population was higher in CuB-NP treated cells. The pro-apoptotic bax, Iκb-α and cleaved PARP levels increased in CuB-NP treated cells, while anti-apoptotic Bcl-2 and NF-κB levels decreased. The caspase (+) cell population was higher in nanoparticle-treated group as 14.20 ± 0.56% and the findings obtained from the caspase assay were also compatible with western blot data. Overall, both CuB and CuB-NP demonstrated anticancer activity, while the lipid polymer hybrid nanoparticle formulation of CuB indicated that the nanoparticle formulation has more promising effect for the treatment of breast cancer.

SLN enriched hydrogels for dermal application: Full factorial design study to estimate the relationship between composition and mechanical properties.

When considering dermal administration of cosmeceuticals and/or drugs, the stratum corneum layer of the skin, has a barrier function that limits the penetration of active substances to the targeted skin tissues. Solid lipid nanoparticles/SLNs are colloidal carrier systems, which show superiority in dermal administration of cosmeceuticals/drugs. This superiority results from the ability of the SLNs to penetrate the skin layers easily. However, the main problem in dermal administration of colloidal drug systems is the need for a suitable semisolid vehicle for application as well as patient compliance. The main purpose of this study is to investigate the relationship between hydrogels and SLNs by using 32 full factorial design which simplifies the process by establishing the relationship between variables. Two different types of gel forming agent, hydroxypropyl methylcellulose or Carbopol 934 P, in three different polymer concentration used for preparation of SLN-enriched hydrogels. Formulations evaluated for their hardness and cohesiveness by using 32 full factorial design and the optimum formulations obtained for both gelling agents. As a result, mechanical properties of hydrogels consisting either hydroxypropyl methylcellulose or Carbopol 934 P revealed promotive results for dermal application of SLNs. The type and concentration of the gel-forming agent which is selected as a semisolid carrier for lipid nanoparticles are basic parameters affecting the dermal behavior of the system.

Comparative Evaluation of Nimesulide-Loaded Nanoparticles for Anticancer Activity Against Breast Cancer Cells.

Recent clinical and epidemiological researches have declared that non-steroidal anti-inflammatory agents may display as antineoplastic agents and indicate pro-apoptotic and antiproliferative effects on cancer cells. The major purpose of this research was to develop a novel poly(ethyleneglycol)-block-poly(ε-caprolactone) (PEG-b-PCL) nano-sized particles encapsulated with nimesulide (NMS), a selective COX-2 inhibitor, and to evaluate its anticancer activity against MCF-7 breast cancer cells. NMS-encapsulated PEG-b-PCL nanoparticles were fabricated using three different production techniques: (i) by emulsion-solvent evaporation using a high shear homogenizer, (ii) by emulsion-solvent evaporation using an ultrasonicator, and (iii) by nanoprecipitation. Nanoparticles were evaluated with respect to the entrapment efficiency, size characteristics, drug release rates, thermal behavior, cell viability assays, and apoptosis. The resulting nanoparticles were found to be spherical shapes with negative surface charges. The average diameter of all nanoparticles ranged between 148.5 and 307.2 nm. In vitro release profiles showed that all nanoparticles exhibited a biphasic release pattern. NMS-loaded PEG-b-PCL nanoparticles demonstrated significant anticancer activity against MCF-7 breast cancer cells in a dose-dependent manner, and the effects of nanoparticles on cell proliferation were significantly affected by the preparation techniques. The nanoparticles developed in this work displayed higher potential for the NMS delivery against breast cancer treatment for the future.

DEVELOPMENT OF SOLID LIPID NANOCARRIERS FOR ORAL DELIVERY OF CANDESERTAN CILEXETIL.

Candesertan cilexetil is a Biopharmaceutics Classification System (BCS) Class II drug possessing high permeability but low aqueous solubility; hence its oral bioavailability is limited in terms of the solubility rate. The aim of this research was to develop solid lipid nanopa rticle (SLN) drug delivery systems of candesertan cilexetil to enhance its aqueous solubility, thereby improving the oral bioavailability of the drug. SLN formulations were produced using a combined technique of high shear homogenization and ultrasonication method. Drug/lipid and surfactant/co-surfactant ratios of the candesertan cilexetil loaded SLNs were investigated based on various final characteristics of the nanocarriers; namely, encapsulation efficiency, average particle diameter, size distribution, surface charge, thermal behavior, and in vitro drug release profiles. Lipid based nanocarriers of candesertan cilexetil displayed spherical particles having a nanometer size. High encapsulation efficiencies were obtained due to the high lipid solubility of the drug. DSC analysis demonstrated the transformation of the crystalline structure of candesertan cilexetil to amorphous form into the SLN formulations and there was no interaction between the drug and the excipients. Consequently, the oral delivery of candesertan cilexetil with the design of Compritol® 888 ATO based lipid nanocarriers may lead to an increase in bioavailability of the drug and thus, more effective therapy may be obtained.

Optimization of a validated stability-indicating RP-LC method for the determination of fulvestrant from polymeric based nanoparticle systems, drugs and biological samples.

Fulvestrant is used for the treatment of hormone receptor-positive metastatic breast cancer in postmenopausal women with disease progression following anti-estrogen therapy. Several reversed-phase columns with variable silica materials, diameters, lengths, etc., were tested for the optimization study. A good chromatographic separation was achieved using a Waters X-Terra RP(18) column (250 × 4.6 mm i.d. × 5 µm) and a mobile phase, consisting of a mixture of acetonitrile-water (65:35; v/v) containing phosphoric acid (0.1%). The separation was carried out 40 °C with detection at 215 nm.The calibration curves were linear over the concentration range between 1.0-300 and 1.0-200 µg/mL for standard solutions and biological media, respectively. The proposed method is accurate and reproducible. Forced degradation studies were also realized. This fully validated method allows the direct determination of fulvestrant in dosage form and biological samples. The average recovery of the added fulvestrant amount in the samples was between 98.22 and 104.03%. The proposed method was also applied for the determination of fulvestrant from the polymeric-based nanoparticle systems. No interference from using polymers and other excipients was observed in in vitro drug release studies. Therefore an incorporation efficiency of fulvestrant-loaded nanoparticle could be determined accurately and specifically.