Bio-composite materials with optimal mechanical and structural properties and capability of cell differentiation are crucial for tissue engineering. Synthetic collagen proteins with lengths of approximately 10 nanometers, along with natural spider silk proteins provide an opportunity for development of an optimal biomaterial for scaffolding applications in tissue engineering. This combines unique mechanical, structural and biological properties of two of the nature’s best polymer proteins, albeit the collagen used in the present work is of the synthetic nature, it mimics the properties and advantages of natural collagen itself. In the present work, we study the binding capability of these proteins at a molecular level via molecular dynamics modeling. Spider silk and synthetic collagen protein molecular models in biophysical saline conditions under standard pressure and temperature are investigated to understand if natural binding occurs between the two without any other external factors. An initial minimum separation of 10 angstroms between the proteins was used. Binding was observed between the two proteins throughout the dynamic simulation of 100 nanoseconds. The radius of gyration and minimum distance between the proteins shows a decreasing separation between the two proteins until a stable distance of 2.5 nanometers and 0.2 nanometers respectively, is achieved. Binding is further observed between the proteins via formation of strong and stable hydrogen bonds. A hydrogen bond between collagen Proline-31 and silk Serine-96 was observed to be the most stable and frequent bond between the single collagen and silk system. Results clearly indicate a self-assembly behavior of these two systems illustrating their potential as a biomaterial for tissue engineering.

Silver nanoparticles (Ag NPs) have unique optical, electrical, and thermal properties and are being incorporated into products that range from photovoltaics to biological and chemical sensors. The production of silver nanoparticles has been increasing worldwide in the nanotechnology industry due to the variety of applications and are very likely to reach aquatic ecosystems damaging them. Due to their small size and high surface area to volume ratio of NPs, they can strongly interact with life cells and cause damage to tested animals. Based on the mentioned previously, it is necessary to evaluate the silver nanoparticle nanotoxicity in aquatic ecosystems to prevent possible ingestion or transfer to humans. Also, the research will benefit aquatic systems due to less pollution around aquatic organisms. The objectives of this research included: i) production and characterization of stable silver nanoparticles in water, ii) characterizing the optical properties by UV-Vis spectroscopy and morphology by HR-TEM and; iii) evaluate the toxicity of silver nanoparticles in aquatic organisms, i.e Artemia salina. Results obtained evidenced that Ag NPs showed an intense absorption peak at 448 nm. This broad peak is due to the phenomenon called surface plasmon resonance (SPR) that is responsible for a variety of phenomena, including nanoscale optical focusing, negative refraction, and surface-enhanced Raman scattering. HR-TEM measurements evidenced the spherical form of the nanoparticles and its small size at around 12-20 nm. In addition, Electron Diffraction analyses suggested the composition of the nanoparticle, which contained only Ag0. The toxicity assays were evaluated using different concentrations of purified Ag NPs. During the cytotoxicity assay, it was demonstrated that Ag NPs were not toxic to Artemia salina after 24 and 48 hours of exposure. However, silver (as silver nitrate) evidenced high toxicity to Artemia salina at larval stage.

RNA delivery into deep tissues with dense extracellular matrix (ECM) has been challenging. For example, cartilage is a major barrier for RNA and drug delivery due to its avascular structure, low cell density and strong negative surface charge. Cartilage ECM is comprised of collagens, proteoglycans, and various other noncollagneous proteins with a spacing of 20nm. Conventional nanoparticles are usually spherical with a diameter larger than 50-60nm (after cargo loading). Therefore, they presented limited success for RNA delivery into cartilage. Here, we developed Janus base nanotubes (JBNTs, self-assembled nanotubes inspired from DNA base pairs) to assemble with small RNAs to form nano-rod delivery vehicles (termed as “Nanopieces”). Nanopieces have a diameter of ∼20nm (smallest delivery vehicles after cargo loading) and a length of ∼100nm. They present a novel breakthrough in ECM penetration due to the reduced size and adjustable characteristics to encourage ECM and intracellular penetration.

Superporous Carboxy Methyl Cellulose (CMC) cryogels were synthesized by chemical crosslinking of linear CMC with divinyl sulfone (DVS) with different mole ratios of CMC repeating unit down to 2.5%. The morphology of macroporous CMC cryogels was visualized by optic microscope and scanning electron microscope (SEM) images. The swelling capacity and pore volume of CMC cryogels were found to increase with the decrease in the ratio of crosslinker to CMC, and the highest swelling capacity and pore volume values were 10825±1799% and 22.1±0.4 mL/g for 2.5% mole ratio of crosslinked CMC cryogels. The blood compatibility of CMC cryogels revealed that blood cells were destroyed with very low hemolysis ratio of 1.09±1% and also showed less thrombogenic activity with 80.2±5.1% blood clotting indexes.

C-reactive protein (CRP) and cardiac troponin I (cTnI) biomolecules represent the earliest enzymes that appear in the blood when a cardiac injury occurs. Real-time and selective detection of these biomarkers is essential for the prediction and detection of cardiovascular diseases at an early stage. Here we report on the label-free specific detection of both proteins at picomolar concentrations using fabricated nanowire-based biosensors. We demonstrate a novel functionalization technique based on the attachment of dibenzocyclooctyne (DBCO)-linked troponin-specific aptamers to azide-functionalized silicon (Si) nanowire (NW) surface. Due to the fast and reliable immobilization of cTnI-specific aptamers and CRP-specific antibodies on the Si NWs, the fabricated devices can rapidly detect target biomolecules demonstrating high sensitivity. We confirm the attachment of proteins to the surface of Si NWs by atomic force microscopy (AFM). Moreover, we demonstrate that nanowire structures of different sizes enable the detection of biomarkers in a wide concentration range (from 1 pg/ml to 1 µg/ml), corresponding to CRP and cTnI elevation levels during the early stage of disease formation.

Plants produce energy in a sustainable way, they are very effective in converting light energy into a useable form. Utilising certain parts of plants in technology could become an efficient way to enhance energy production and improve sustainability. Integrating plants with technology would offer a ‘green’ way of producing elements for electronic circuits and reduce heavy metal waste. In this paper, we demonstrate that conducting polymers can be incorporated into living system such as celery. Electrical impedance analysis was used to establish the conductivity of celery with a conducting polymer (PEDOT:PSS) into its vascular system. It was demonstrated that electronic celery exhibited conductivity values of up to 0.55 ± 0.03 S/cm. This conductivity value was sufficient to demonstrate the potential of celery electronics where celery stalks are used as electrodes in simple circuits.