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Iron fortification in food is considered as an important way to prevent and treat iron deficiency. However, adding iron in food can affect flavor, color, and oxidation of fat components. Encapsulation of iron can solve the drawbacks of taste, color, and reactivity of iron in oral iron consumption without adverse effect on food quality. The aim of this work was to nanoencapsulate iron into pectin (Pec) nanoparticles (NP) by ion gelation method to prevent undesirable sensorial changes in foods and improve bioavailability of iron. The effect of different parameters including pectin concentration (Pec Con), FeSO4 concentration (Fe Con), and volumetric ratio of Fe solution to Pec solution on iron loaded Pec nanoparticles (IP NP) size was investigated. Morphology, size, surface charge, and physicochemical features of the optimized particles were characterized. The iron released from IP NP was studied, and the mathematical model of release was extracted. Pec Con exhibited a direct effect on particle size. The optimized IP NP (Pec solution 0.1% (w/w), Fe solution 0.05% (w/w), and Pec/Fe: 2) had a hydrodynamic diameter of 417 nm with zeta potential of −11.7 mV and polydispersity index (PDI) of 0.13, with a nearly spherical morphology. Scanning electron microscopy (SEM) represented the mean size of 58 nm. Iron loading was about 7.5 ± 1.5%. FTIR results confirmed the interaction of iron ions with the hydroxyl and carboxyl groups of Pec. The results of differential scanning calorimetric (DSC) indicated the interaction of Pec with iron. The release profile of iron in all pH of 2, 6, and 7.4 showed a burst release at the beginning and then a sustained release occurred. In all three pH values, the mathematical model of release was Korsmeyer-Peppas with the highest R2 value. Therefore, encapsulation of iron using pectin have a high potential to make nanoparticles with appropriate properties, which can be helpful for iron fortification of food. [ABSTRACT FROM AUTHOR]

An electrochemical immunosensor based on carbon nanofibers (CNFs) and gold nanoparticles (AuNPs) was developed for detecting anti-Toxoplasma gondii antibodies (anti-T. gondii) IgG in human serum. CNFs were produced using electrospinning and carbonization processes. Screen-printed carbon electrode (SPCE) surface was modified with CNFs and AuNPs which were electrodeposited onto the CNFs. Then, T. gondii antigen was immobilized onto the AuNPs/CNFs/SPCE. Afterward, anti-T. gondii IgG positive serum samples were coated on the modified electrode and assessed via adding anti-human IgG labeled with horseradish peroxidase (HRP) enzyme. The morphology of SPCE, CNFs, and AuNPs/CNFs/SPCE surface was characterized using field emission scanning electron microscopy (FESEM) equipped with energy dispersive spectroscopy (EDS). Characterization of CNFs was evaluated by Raman spectroscopy and X-ray diffraction (XRD). Electrochemical characterization of the immunosensor was verified using cyclic voltammetry (CV), and electrochemical response of modified electrode for anti-T. gondii IgG was detected via differential pulse voltammetry (DPV). This immunosensor was detected in the range 0–200 U mL−1 with a low detection limit (9 × 10−3 U mL−1). In addition, the proposed immunosensor was exhibited with high selectivity, strong stability, and acceptable reproducibility and repeatability. Furthermore, there was a strong correlation between results obtained via the designed immunosensor and enzyme-linked immunosorbent assay (ELISA) as gold standard. In conclusion, the developed immunosensor is a promising route for rapid and accurate clinical diagnosis of toxoplasmosis. [ABSTRACT FROM AUTHOR]

An electrochemical aptamer-based sensor was designed to detect tetracycline (Tet) in chicken ham. First, polyacrylonitrile (PAN) polymer was used to prepare electrospun PAN nanofibers. PAN nanofibers were heat treated to form electrospun carbon nanofiber (CNF) mat. The electrospun CNF mat electrode was modified with Au and the aptamer of Tet was placed on the mat electrode. Raman spectroscopy and scanning electron microscopy equipped with energy-dispersive spectroscopy were used to identify the structure and morphology of electrospun CNFs, respectively. The behavior of CNF mat electrode was evaluated via cyclic voltammetry. The designed aptamer biosensor had a good repeatability, reproducibility, stability, and specific function for the detection of Tet in chicken ham. This biosensor was able to detect the Tet in the linear range of 1 × 10–9 M to 1 × 10–4 M with the detection limit of 1.2 × 10–10 M and preserve about 95% of its primary response after 20 days. In addition, the recoveries of Tet were achieved ranging from 96.92 to 104.31%. [ABSTRACT FROM AUTHOR]

The aim of this work was to design and develop an electrochemical immunosensor based on electrospun carbon nanofiber (ECNF) mat for the detection of human epidermal growth factor receptor 2 (Her-2). First, ECNF mat was fabricated by electrospinning method and heat-treatment and used directly as a novel electrode. To determine Her-2, this ECNF mat electrode was modified by Au nanparticles (NPs), cysteamine (Cys) molecules, carbon nanotubes (CNTs), and antibody (Ab) molecules, respectively. Field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray spectroscopy (EDS) analysis were used to characterize Au NPs modified ECNF mat electrode. In addition, analysis of Her-2 in spiked human blood serum samples were investigated by cyclic voltammetry (CV) using [Fe(CN)6]−3/−4 as a redox probe and the experiments were compared using commercial kit. The linear response range of the developed immunosensor was from 5 to 80 ng ml−1 with a limit of detection (LOD) of 0.45 ng ml−1. The results indicated that the designed immunosensor has high potential for the determination of Her-2 due to non-invasive, precise and rapid analysis. [ABSTRACT FROM AUTHOR]

Purpose: The main purpose of this study was to develop etoposide (ETP) and paclitaxel (PTX) co-loaded methoxy poly(ethylene glycol)-poly(lactic-co-glycolic acid) (mPEG-PLGA) nanoparticles (NPs) with optimized size to achieve co-delivery of ETP and PTX. In addition, the effect of defined parameters including the amount of aqueous to organic phase, the amount of mPEG-PLGA, tween 80 concentration, and PTX to ETP ratio on the size of ETP and PTX co-loaded mPEG-PLGA NPs was investigated. Methods: ETP and PTX co-loaded mPEG-PLGA NPs were prepared by nanoprecipitation technique to avoid the therapeutic limitations. Results: The resultant NPs were spherical with the mean size about 150 nm, − 22.2 mV zeta potentialand high loading efficiency (92.5 ± 4.8% for PTX and 86 ± 3.7% for ETP). Besides, Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) analyses confirmed that the drugs were successfully dispersed as an amorphous phase in the NP matrix without any change in the chemical structures. The NPs exhibited a sustained release profiles to both drugs for 6 days. Conclusion: ETP and PTX co-loaded mPEG-PLGA NPs were optimized using ANN and confirmed optimum physicochemical properties that such NPs could be suggested as a promising method for the enhanced chemotherapy. [ABSTRACT FROM AUTHOR]

In this research, a novel electrochemical aptasensor for the detection of Penicillin in a milk sample was designed using a Penicillin aptamer as the specific recognition element and an electrospun carbon nanofiber (ECNF) mat electrodeposited gold nanoparticles (AuNPs) as the platform. Firstly, the ECNF mat electrode was fabricated by means of electrospinning and heat treatment method. Secondly, the prepared ECNF mat electrode was modified with electrodeposition of AuNPs to improve the rate of electronic transmission. Finally, a Penicillin aptamer was assembled on the modified electrode. The morphology of AuNPs/ECNF mat electrode was examined using scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). The SEM results demonstrated that the electrodeposition of AuNPs on ECNF mat electrode was successfully performed. Cyclic voltammetry (CV) was utilized to indicate the electrochemical performance of the prepared aptasensor. The CV results illustrated a high selectivity, good stability, excellent reproducibility and repeatability as well as wide linear range (1–400 ng/mL) with a low detection limit (0.6 ng/mL). Moreover, the recoveries obtained in this research were in a good agreement with those achieved using the HPLC method. Therefore, a proposed aptasensor with a good electrochemical performance and simple preparation procedure can be proposed for the detection of Penicillin antibiotic in milk samples. [ABSTRACT FROM AUTHOR]

Purpose: Nanoformulations for co-delivery of multiple therapeutics and combinational therapies are expected to provide improved pharmacokinetics, reduced drug toxicities, and avert drug resistance. Methotrexate (MTX) and curcumin (CUR) were chosen as model drugs for this study primarily due to their anticancer activities in different phases of the cell cycle. Methods: The nanoprecipitation technique was used to prepare CUR-, MTX-, and CUR/MTX-co-loaded poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles. Results: Encapsulation and drug loading efficiencies were 87.9% and 8.0% for CUR-loaded PLGA nanoparticles and 81.4% and 13.5% for MTX-loaded PLGA nanoparticles, respectively. In addition, drug co-encapsulation and co-loading efficiencies were 77.2% and 6.5% for CUR and 86.1% and 15.5% for MTX, respectively. The results of cell cycle analysis indicated that CUR- and MTX-loaded PLGA nanoparticles additively complemented each other in the S and sub-G1 phases. The obtained combinational index (CI) also exhibited that CUR- and MTX-loaded PLGA nanoparticles produce additive cytotoxicity at Fa = 0.5 on U87MG glioma cells. In addition, necrosis dominates cell death in nanomediated monotherapy whereas apoptosis dominates co-delivery treatment. The highest amount of LDH released was related to co-delivery as well. Conclusion: Nano-assisted combinational therapy and co-delivery can be used to obtain efficacies of drugs at lower concentrations, thus potentially increasing the therapeutic window of the drugs. [ABSTRACT FROM AUTHOR]

Tissue engineering makes it possible to fabricate scaffolds that can help the function of defective tissues or even the most complex organs such as the heart. Carbon nanofibers (CNFs), because of their high mechanical strength and electrical properties, can improve the functional coupling of cardiomyocytes and their electrophysiological properties. In this study, electroactive CNF/gelatin (Gel) nanofibrous cardiac patches were prepared by an electrospinning method. Scanning electron microscope (SEM) evaluation of prepared scaffolds showed randomly oriented nanofibers. The electrical conductivity of the CNF/Gel scaffolds was assessed by a four-probe device and was in the semiconducting range (~ 10−5 S/m). The result of an MTT assay confirmed the excellent biocompatibility of electroactive CNF/Gel scaffolds. Also, CNF-containing scaffolds supported cardiomyocyte adhesion and increased expression of the cardiac genes including TrpT-2, Actn4, and Conx43 compared with the non-conductive counterpart. Our findings also confirmed the angiogenic potential of CNF/Gel scaffolds as compatible and electroactive platforms for cardiac tissue engineering. [ABSTRACT FROM AUTHOR]

Chitosan/polyethylene oxide (PEO) solution makes electrospun nanofibers with decreased beads and diameters in comparison with lonely chitosan (CS). The aim of this work was to find an artificial neural network (ANN) model for predicting the chitosan/PEO blend electrospun nanofiber diameter. Chitosan/PEO concentration ratio, distance between nozzle tip and collector, applied voltage, and flow rate were considered as input variables, and chitosan/PEO blend electrospun nanofiber diameter was considered as output variable. Scanning electron microscopy images indicated that electrospun nanofiber diameter was approximately 50-185 nm. For increasing validity, k-fold cross validation method was applied to dataset. The ANN technique was used for training and testing via fivefold of dataset. The best results of prediction were obtained via network with three hidden layers including 10, 15, and 5 nodes in each layer, respectively. The mean square error (MSE) and correlation coefficient between the observed and predicted thickness of the nanofibers in the chosen model were about 0.0707 and 0.9630, respectively, indicating the ANN technique validity in the prediction procedure. For the analysis of interactions between the involved electrospinning parameters and nanofiber diameter, 3D graphs in various levels were plotted. In conclusion, the results indicated that using the prediction process via ANN could be relevant in the decision to produce nanofibers with desired shape and diameter via electrospinning. [ABSTRACT FROM AUTHOR]

Among polymers, polyaniline (PANi) has been introduced as a good candidate for muscle regeneration due to high conductivity and also biocompatibility. Herein, for the first time, we report the use of electrospun nanofibrous membrane of PAN-PANi as efficient scaffold for muscle regeneration. The prepared PAN-PANi electrospun nanofibrous membrane was characterized by scanning electron microscopy (SEM), Attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR) and tensile examination. The softer scaffolds of non-composite electrospun nanofibrous PAN govern a higher rate of cell growth in spite of lower differentiation value. On the other hand, PAN-PANi electrospun nanofibrous membrane exposed high cell proliferation and also differentiation value. Thank to the conductive property and higher Young's modulus of composite type due to the employment of PANi, satellite cells were induced into more matured form as analyzed by Real-Time PCR. On the other hand, grafting of composite nanofibrous electrospun scaffold with gelatin increased the surface stiffness directing satellite cells into lower cell proliferation and highest value of differentiation. Our results for first time showed the significant role of combination between conductivity, mechanical property and surface modification of PAN-PANi electrospun nanofibers and provid new insights into most biocompatible scaffolds for muscle tissue engineering. Graphical abstract: The schematic figure conveys the effective combination of conductive and surface stiffness on muscle tissue engineering. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The purpose of this work was to fabricate an electrochemical DNA biosensor for detecting hepatitis B virus. Gold nanorods (GNRs), which are known for their conductivity, were used to increase surface area and consequently increase the immobilization of single-stranded DNA (ss-DNA) on the modified gold electrode. The GNRs were characterized via transmission electron microscopy. The morphology of the gold electrode before and after modification with GNRs was characterized by scanning electron microscopy. Atomic-force microscopy was used to evaluate the morphology of the GNR electrode surface before and after interaction with ss-DNA. Cyclic voltammetry was used to monitor DNA immobilization and hybridization, using [Co(phen)] as an electrochemical indicator. The target DNA sequences were quantified at a linear range from 1.0 × 10 to 10.0 × 10 mol L, with a detection limit of 2.0 × 10 mol L by 3 σ. The biosensor had good specificity for distinguishing complementary DNA in the presence of non-complementary and mismatched DNA sequences. [ABSTRACT FROM AUTHOR]

The restoration of defective bone tissue and complications related to surgery and fracture site infection are major concerns in orthopedic surgeries. However, it is crucial to develop osteoconductive and bacteriostatic composites. Chitosan/nano hydroxyapatite (CT/n-HAp) powder containing of Ag and Si were prepared by an in situ hybridization method. The aim of this work was to elucidate the effect of size, surface roughness, and chemical structure of mentioned nanocomposites on cytotoxicity and bacteriostatic activity via human osteoblast cells and Escherichia Coli, respectively. Particle size, surface roughness, reactive oxygen specious production, and bioactivity of nanocomposites were investigated by X ray diffraction, atomic force microscopy, DPPH assay, and SEM/UV–Visible spectrophotometer, respectively. Bacterial colony counting test, MTT assay and lactate dehydrogenase (LDH) release were performed as bacteriostatic and biocompatibility tests. The results showed that CT/n-HAp/Ag with smaller particle size in the range of 1–22.6 nm (10.00 ± 0.09 nm) than CT/n-HAp/Si in the range of 3–72.5 nm (18.00 ± 0.14 nm) exhibits higher cell viability and bacteriostatic activity, and less LDH release from cell plasma membrane. Integration of Ag into the nanocomposite hindered the release of Ag+ ions and restricts cytotoxic potential on cells. Higher cytotoxic effect of CT/n-HAp/Si might be related to proton concentration derived from nanocomposite and its chemical structure. In conclusion, the strong bone regeneration potential of CT/n-HAp and good biocompatibility and bacteriostatic activity of CT/n-HAp/Ag make it as potential bacteriostatic bone filler in site of infected bone fracture. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate the effective parameters for prediction of the electrospun gelatin nanofibers diameter using artificial neural network (ANN) technique. The various sets of electrospinning process including temperature, applied voltage and polymer and solvent concentrations were designed to produce pure gelatin nanofibers. The obtained results by analyzing Scanning Electron Microscopy (SEM) images indicated that the produced nanofibers diameter was in the range of 85 to 750 nm. Due to the volume of the data, k fold cross-validation method was used for data setting. Data were divided into the five categories and trained and tested using ANN technique. The results indicated that the network including 4 input variables, 3 hidden layers with 10, 18 and 9 nodes in each layers, respectively, and one output layer had the best performance in the testing sets. The mean squared error (MSE) and linear regression (R) between observed and predicted nanofibers diameter were 0.1531 and 0.9424, respectively. The obtained results demonstrated that the selected neural network model had acceptable performance for evaluating involved parameters and prediction of nanofibers diameter. [ABSTRACT FROM AUTHOR]

cysteamine (CysAm) nanostructure was generated to act as an intermediate layer between gold electrode and carbon nanotubes. A bare gold electrode was placed in a solution of CysAm to create a self-assembled monolayer on its surface. The modified electrode was then incubated with a solution of multi-walled carbon nanotubes. Cyclic voltammetry and atomic force microscopy were used to characterize the modified electrode. The results indicated that the number of functionalized MWCNTs on the surface of the electrodes increased by enhancing incubation time. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Inflammatory responses play a crucial role in the pathophysiology of spinal cord injury (SCI) and developing new approaches to establish an anti-inflammatory environment for the promotion of neuroregeneration holds promise as a potential approach. In this study, our aim was to investigate the potential of combining an acellular spinal cord scaffold (ASCS) with quercetin-loaded bovine serum albumin (Qu/BSA) nanoparticles (NPs) for the treatment of SCI. The ASCS was prepared using physical and chemical methods, while the Qu/BSA NPs were prepared through a desolvation technique. The NPs exhibited favorable characteristics, including a mean size of 203 nm, a zeta potential of –38, and an encapsulation efficiency of 96%. Microscopic evaluation confirmed the successful distribution of NPs on the walls of ASCS. Animal studies revealed that Qu/BSA NPs group exhibited a significant decrease in NLRP3, ASC, and Casp1 gene expression compared to the SCI group (p < 0.0001). The findings indicated a significant decrease in the NLRP3, ASC, and Casp1 protein level between the Qu/BSA/ASCS group and the SCI group (p < 0.0001). Moreover, treatment with ASCS containing either blank BSA (B/BSA) NPs or Qu/BSA NPs effectively promoted functional recovery via increasing the amount of nestin- and glial fibrillary acidic protein (GFAP)-positive cells in the site of injury. Notably, Qu/BSA/ASCS exhibited superior outcomes compared to B/BSA/ASCS. Overall, the combination of ASCS with the Qu delivery system presents a promising therapeutic approach for SCI by inhibiting inflammatory responses and promoting neuroregeneration, leading to the restoration of motor function in animals. This study demonstrates the potential of utilizing biomaterials and NPs to enhance the effectiveness of SCI treatment.Note: Graphic abstract was designed with Biorender (https://biorender.com/).Graphical abstract: Inflammatory responses play a crucial role in the pathophysiology of spinal cord injury (SCI) and developing new approaches to establish an anti-inflammatory environment for the promotion of neuroregeneration holds promise as a potential approach. In this study, our aim was to investigate the potential of combining an acellular spinal cord scaffold (ASCS) with quercetin-loaded bovine serum albumin (Qu/BSA) nanoparticles (NPs) for the treatment of SCI. The ASCS was prepared using physical and chemical methods, while the Qu/BSA NPs were prepared through a desolvation technique. The NPs exhibited favorable characteristics, including a mean size of 203 nm, a zeta potential of –38, and an encapsulation efficiency of 96%. Microscopic evaluation confirmed the successful distribution of NPs on the walls of ASCS. Animal studies revealed that Qu/BSA NPs group exhibited a significant decrease in NLRP3, ASC, and Casp1 gene expression compared to the SCI group (p < 0.0001). The findings indicated a significant decrease in the NLRP3, ASC, and Casp1 protein level between the Qu/BSA/ASCS group and the SCI group (p < 0.0001). Moreover, treatment with ASCS containing either blank BSA (B/BSA) NPs or Qu/BSA NPs effectively promoted functional recovery via increasing the amount of nestin- and glial fibrillary acidic protein (GFAP)-positive cells in the site of injury. Notably, Qu/BSA/ASCS exhibited superior outcomes compared to B/BSA/ASCS. Overall, the combination of ASCS with the Qu delivery system presents a promising therapeutic approach for SCI by inhibiting inflammatory responses and promoting neuroregeneration, leading to the restoration of motor function in animals. This study demonstrates the potential of utilizing biomaterials and NPs to enhance the effectiveness of SCI treatment.Note: Graphic abstract was designed with Biorender (https://biorender.com/). [ABSTRACT FROM AUTHOR]