Biocompatible Template Research Articles

Evaluation of cytotoxic activity against A549 human lung cancer cells using green synthesized N-Cholyl D-Penicillamine encapsulated silver and gold nanoparticles

Synthesis of noble metal nanoparticles (MNPs) using a biocompatible template provides a biologically safe, cost effective, and environment friendly approach in view of biomedical applications. In this manusctipt, synthesis of gold and silver nanoparticles (Au and Ag NPs) using N-cholyl D-penicilamine (NCPA) as an effective reducing and stabilizing agent at below the critical micellar concerntration (CMC) under sunlight exposure has been reported. The formation of NPs were optimized by changing the concentration of NCPA and pH of the medium. The synthesized Au and Ag NPs were characterized by UV-visible, FT-IR, DLS, Zeta potential and HR-TEM techniques. The average size of Au and Ag NPs were found to be 10.3 ± 0.4 and 9.1 ± 0.6 nm, respectively and exhibit stability for more than six month. The prepared NPs showed low toxicity on human erythrocytes (RBCs) even at their higher concentrations (120 μg/mL). The anticancer activity of NCPA capped NPs on A549 cells were investigated by cell viability assay, apoptosis analysis using MTT assay and Acridine Orange/Propidium Iodide (AO/PI) dual fluorescent staining asay. The results obtained from these studies suggest that the synthesized NPs showed potent cytotoxicity on A549 cells in a dose-dependent manner. Further, AgNPs showed better cytotoxicity as compared to AuNPs.

Near‐Infrared I/II Nanophosphors with Cr3+/Ni2+ Energy Transfer for Bioimaging

AbstractIn the biomedical field, the use of fluorescence imaging in the second near‐infrared (NIR‐II) region is growing rapidly because it imparts the advantages of reduced autofluorescence and low photon scattering. The advantage of reduced scattering is that it increases penetration depth in vivo and improves imaging clarity. Herein, this work uses mesoporous silica, a biocompatible template that can be easily modified, functionalized, and loaded with drugs for use in several bioapplications. The ZnGa2O4 spinel oxide system is integrated into mesoporous silica and different concentrations of Cr3+ and Ni2+ are loaded in octahedral sites to obtain the highest emission intensity in the NIR‐II region at 1285 nm via energy transfer from Cr3+ to Ni2+. Given that only a few nanophosphor systems with emission in the NIR‐II region are available, this work attempts to establish emission in the NIR‐II and NIR‐I regions to obtain images in vivo with an increased penetration depth to 5 mm and improved clarity for bioimaging purposes. This system will open the door for biomedical research on other NIR‐II nanophosphors.

Double scaffold networks regulate edible Pickering emulsion gel for designing thermally actuated 4D printing

3D and 4D printing of emulsion gels can be achieved by controlling the continuous phase and the interface. Edible high internal phase water-in-oil Pickering emulsion gels (PEGs) with a tunable double scaffold network structure are designed and prepared by food-grade phytosterol nanoparticles (PPs). In PEGs, PPs through hydrogen bonding enable binding of emulsion droplets to form the first scaffold network, giving PEGs high viscoelasticity for 3D printing. In the continuous oil phase, palm kernel stearin (PKST) can crystallize forming the second scaffold network of crystals to reinforce 3D printed objects of PEGs. The PEG can be used as a biocompatible template to engineer edible and rigid porous materials with adjustable strength and pore size depending on the degree of curing. 4D printing of PEGs is achieved by the thermal response of the PKST crystal network, leading to the unlimited potential of highly biocompatible PEGs in many applications.

Single-step Synthesis and Characterization of Zr-MOF onto Wool Fabric: Preparation of Antibacterial Wound Dressing with High Absorption Capacity

Improvement of curative herbal extracts effectiveness through novel drug delivery systems is a field of study for the researches nowadays. Zirconium-based metal-organic frameworks (Zr-MOFs) are one of the most capable porous nanocarriers that need a biocompatible template to be used in biomedical applications. In this work, Zr-MOF was synthesized into the wool fabric through in-situ one-pot method with different molar ratios. The final fabrics were characterized thoroughly using various techniques and the effect of components on monodispersity and nucleation tendency of Zr-MOF onto the surface of wool were explained. The resultant fabric stablished absolute wash durability, increased air-permeability up to twice and reasonable hydrophilicity. Tensile strength and young modulus decreased 30 and 1244 % and strain increased 66 %. Salvia Officinalis (SO) and Calendula Officinalis (CO) extracts were loaded onto the modified fabrics with 1154 and 1842 % increased absorption capacity. The release profiles showed domination of diffusion mechanism. The wool-MOF-SO and CO displayed both 100 % antibacterial activity against Escherichia coli and 60.95 and 64.64 % against Staphylococcus aureus because of diverse antibacterial components. Calendula Officinalis proved biocompatibility with human skin however Salvia Officinalis exhibited high toxicity.

Premium ethylcellulose polymer based architectures at work in drug delivery

Premium ethylcellulose polymers are hydrophobic cellulose ether based biomaterials widely employed as biocompatible templates for the design of novel drug delivery systems. They are classified as United States Food and Drug Administration Generally-Recognized-As-Safe chemical substances and have been extensively utilized within the biomedical and pharmaceutical industries for over half a century. They have so far demonstrated the potential to modulate and improve the physiological performance of bioactives leading to the desired enhanced prophylactic and therapeutic outcomes. This review therefore presents a scholarly survey of inter-disciplinary developments focused on the functionalities of ethylcellulose polymers as biomaterials useful for the design of smart delivery architectures for relevant pharmacotherapeutic biomedical applications. Emphasis was placed on evaluating scientific resources related to recent advancements and future directions associated with its applications as delivery systems for drugs and biologics within the past decade thus complementing other specialized reviews showcasing the theme.

The Effect of Phosphorous Doping on the Composition and Capacitance Properties of Mesoporous Graphitic Carbon Nitride

The effect of phosphorus doping on the composition and capacitance properties of mesoporous graphitic carbon nitride (MGCN) is investigated systemically and reported in this article. Pristine and phosphorous doped MGCN are synthesized by using a bio-compatible template, carboxymethyl cellulose, and orthophosphoric acid as a dopant. Powder X-ray diffraction and transmission electron microscopic studies confirm the formation of stacked layers of MGCN. Vibrational and X-ray photoelectron spectroscopic studies reveal that phosphorus is doped preferentially on the sites of carbon and, thereby induces defects. The defect and surface area are found to increase on increasing the dopant concentration. Owing to the presence of functionalities, such as P-O and C-P, P-doped MGCN delivers higher specific capacitance than pristine MGCN at all current rates. A symmetrical supercapacitor device fabricated using the electrodes of MGCN synthesized using 0.5 g of dopant delivers an energy density of 17.22 Wh kg−1 at a power density of 500 W kg−1.

Rapid and Versatile Cell Aggregate Formation Using Lipid-Conjugated Heparin.

Cell aggregates hold significant therapeutic promise for in vitro cell analysis, ex vivo tissue models, and in vivo cell therapy and tissue engineering. Traditional methods of making cell aggregates require long incubation times and can only produce three-dimensional-spheroid-shaped aggregates. We propose a novel method of making cell aggregates of diverse sizes and shapes using lipid-conjugated heparin. Shaking the cell suspension containing a small amount of lipid-conjugated heparin for approximately 30 min produced cell aggregates. This approach can be applied to any cell type, including stem cells, fibroblast cells, and T lymphocytes. The shape of biocompatible templates could modulate the shape of cell aggregates. In addition to layered, multicompartmental cell aggregates on template, template-free, tube-shaped cell aggregates could also be made. The cell aggregates formed were alive and maintained biological activities.

Tannic acid assisted copper oxide nanoglobules for sensitive electrochemical detection of bisphenol A

ABSTRACTThis study describes the development of an electrochemical sensor system for the determination of bisphenol A using tannic acid functionalized CuO nanoglobules. The utilized tannic acid acted simultaneously as both bio-compatible template and functionalizing agent for the as-synthesised CuO nanostructures. The excellent synergy of high surface area and favorable interactions between the moieties of tannic acid and bisphenol A molecules enabled sensitive electrochemical oxidation of bisphenol A within wide detection window (0.1–5.5 µM) and limit of detection estimated to be 0.01 µM. Moreover, the sensor exhibited satisfactory stability and strong anti-interference capability when evaluated against common interferents molecules such as phenol, hydroquinone, and 4-nitrophenol.

Amino acid assisted growth of CuO nanostructures and their potential application in electrochemical sensing of organophosphate pesticide

This work reports a highly sensitive electrochemical sensor for organophosphate pesticide (malathion) based on unique and attractive CuO nanostructures. The discussed nanostructures were synthesized using low temperature hydrothermal growth method utilizing green amino acids such as glycine, serine, threonine and histidine as effective bio-compatible templates. The morphological evaluation demonstrated formation of unique and attractive 1-D nanostructures reflecting the effective growth controlling and directing capabilities of the utilized amino acids. The as-synthesized CuO nanostructures were noted to possess high affinity towards malathion which enabled their application as electrode material for the development of affinity based electrochemical sensor. Although, the as-synthesized morphologies were all sensitive towards malathion but the glycine directed triangular flake-like nanostructures exhibited greater sensitivity compared to other competitors. The electrochemical behaviour of the modified electrodes was studied using cyclic voltammetry (CV) whereas, differential pulse voltammetry (DPV) was utilized for the analytical evaluation of the sensor. The developed sensor demonstrated high reproducibility, stability, wide detection window (1–12nM), and sensitivity to detect malathion up to 0.1nM based on suppressive signal measurement. In addition, the sensor system exhibited high anti-interference capability in the presence of common co-existing pesticides like lindane, carbendazim, and trichlorfon. The developed sensor provides an effective measure for detecting extremely low concentration of malathion with wide applicability in various fields.

A radiopaque electrospun scaffold for engineering fibrous musculoskeletal tissues: Scaffold characterization and in vivo applications

Tissue engineering strategies have emerged in response to the growing prevalence of chronic musculoskeletal conditions, with many of these regenerative methods currently being evaluated in translational animal models. Engineered replacements for fibrous tissues such as the meniscus, annulus fibrosus, tendons, and ligaments are subjected to challenging physiologic loads, and are difficult to track in vivo using standard techniques. The diagnosis and treatment of musculoskeletal conditions depends heavily on radiographic assessment, and a number of currently available implants utilize radiopaque markers to facilitate in vivo imaging. In this study, we developed a nanofibrous scaffold in which individual fibers included radiopaque nanoparticles. Inclusion of radiopaque particles increased the tensile modulus of the scaffold and imparted radiation attenuation within the range of cortical bone. When scaffolds were seeded with bovine mesenchymal stem cells in vitro, there was no change in cell proliferation and no evidence of promiscuous conversion to an osteogenic phenotype. Scaffolds were implanted ex vivo in a model of a meniscal tear in a bovine joint and in vivo in a model of total disc replacement in the rat coccygeal spine (tail), and were visualized via fluoroscopy and microcomputed tomography. In the disc replacement model, histological analysis at 4weeks showed that the scaffold was biocompatible and supported the deposition of fibrous tissue in vivo. Nanofibrous scaffolds that include radiopaque nanoparticles provide a biocompatible template with sufficient radiopacity for in vivo visualization in both small and large animal models. This radiopacity may facilitate image-guided implantation and non-invasive long-term evaluation of scaffold location and performance. Statement of SignificanceThe healing capacity of fibrous musculoskeletal tissues is limited, and injury or degeneration of these tissues compromises the standard of living of millions in the US. Tissue engineering repair strategies for the intervertebral disc, meniscus, tendon and ligament have progressed from in vitro to in vivo evaluation using a variety of animal models, and the clinical application of these technologies is imminent. The composition of most scaffold materials however does not allow for visualization by methods available to clinicians (e.g., radiography), and thus it is not possible to assess their performance in situ. In this work, we describe a radiopaque nanofibrous scaffold that can be visualized radiographically in both small and large animal models and serve as a framework for the development of an engineered fibrous tissue.

The investigation of novel glucose oxidase biosensor based on graphene-clay nanocomposite

A feasible and fast method to fabricate glucose biosensor was developed by immobilisation of glucose oxidase (GOx) to nano-sepiolite-graphene nanocomposite/glassy carbon electrode. The direct electrochemistry of glucose oxidase not containing medioter and worked in air saturated condition for similarity of in vivo usage. The nano-sepiolite-graphene nanocomposite shows a high conductive and biocompatible template for enzyme immobilisation. The immobilised GOx on nanocomposite shows a couple of well defined reversible peak with the anodic and cathodic peak potentials of –430 and –460 mV (vs. Ag/AgCl), corresponding to the FAD/FADH2 redox couple, and with a formal potential of –445 mV in 0.1 M phosphate buffer solution at pH = 7. The linear concentration rang of biosensor is 0.14–3.14 µM, and with detection limit of 0.04 µM. Also, the life time of biosensor is more than four months.

Enhanced optical breakdown in KB cells labeled with folate-targeted silver-dendrimer composite nanodevices

Enhanced optical breakdown of KB tumor cells folate-targeted with silver-dendrimer composite nanodevices (CNDs) is described. CNDs [(Ag 0) 25-PAMAM_E5.(NH 2) 42(NGly) 74(NFA) 2.7] were fabricated by reactive encapsulation, using a biocompatible template of dendrimer–folic acid (FA) conjugates. Preferential uptake of the folate-targeted CNDs (of various treatment concentrations and surface functionality) by KB cells was visualized with confocal microscopy and transmission electron microscopy. Intracellular laser-induced optical breakdown threshold and dynamics were detected and characterized by high-frequency ultrasonic monitoring of resulting transient bubble events. When irradiated with a near-infrared, femtosecond laser, the CND-targeted KB cells acted as well-confined activators of laser energy, enhancing nonlinear energy absorption, exhibiting a significant reduction in breakdown threshold and thus selectively promoting intracellular laser-induced optical breakdown. From the Clinical Editor This study presents a novel method to selectively destroy cancer cells by combining biochemical targeting with topical laser irradiation. A human epidermoid cancer cell line was targeted with folated silver-dendrimer composite nanodevices and the labeled cancer cells were subsequently destroyed by the microbubbles generated due the enhanced energy uptake of the silver nanoparticles from the laser irradiation, as compared to unlabeled cells.

Synthesis and molecular weight and structural determinations of (polyvinylpyrrolidone)- oximate-silico-benzoyl glycine copolymer with IR and NMR spectroscopy

Polyvinylpyrrolidone (PVP)-oximate-silico-benzoyl glycine (POSBG) copolymer has been prepared taking PVP and benzoyl glycine with tetraethylorthosilicate as binder. Average viscosity molecular weights (Mv) each of PVP-oxime and POSBG were determined with dilute aqueous solutions. For molecular weights primarily a calibration curve between intrinsic viscosities [η] and different molecular weights of polyvinyl alcohol (marker) has been obtained to determine Mv of oxime as 42,042 g mol−1. Similarly the Mv of POSBG as 80,297.13 g mol−1 was determined with [η] of lysozyme (molecular weight = 24,000 g mol−1) egg albumin (40,000 g mol−1) and BSA (65,000 g mol−1). For structural illustration, IR spectra of PVP-oxime and copolymer were recorded in Nujol, which do not depict band frequency of OH group of binder. The 1602, 1688, 1182, and 1127 cm−1 stretching vibration frequencies noted in spectra infer presence of CN, CO, SiOSi, and SiOC groups, respectively, in POSBG. Structures of PVP-oxime unit of POSBG are supported with Proton NMR. The work is aimed to develop new valuable biosensor and conducting copolymer molecule to serve as useful biochip and a biocompatible template. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007