This paper reports the characterization and antibacterial performance evaluation of some spherical and stable crystalline silver (Ag)/copper (Cu) nanocomposites (Ag-CuNCs) prepared in deionized water (DIW) using pulse laser ablation in liquid (PLAL) method. The influence of various laser fluences (LFs) on the structural, morphological, optical and antibacterial properties of these NCs were determined. The UV-Vis absorbance of these NCs at 403 nm and 595 nm was gradually increased accompanied by a blue shift. XRD patterns disclosed the nucleation of highly crystalline Ag-CuNCs with their face centered cubic lattice structure. TEM images showed the existence of spherical NCs with size range of 3-20 nm and lattice fringe spacing of approximately 0.145 nm. EDX profiles of Ag-CuNCs indicated their high purity. The antibacterial effectiveness of the Ag-CuNCs was evaluated by the inhibition zone diameter (IZD) and optical density (OD600) tests against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. The proposed NCs revealed the IZD values in the range of 22-26 mm and 20-25 mm when tested against E. coli and S. aureus bacteria, respectively. The Ag-CuNCs prepared at LF of 14.15 J/cm2 revealed the best bactericidal activity. It is established that by controlling the laser fluence the bactericidal effectiveness of the Ag-CuNCs can be tuned.
Biocompatible polymers have received significant interest from researchers for their potential in diagnostic applications. This type of polymer can perform with an appropriate host response or carrier for a specific purpose. The current study aims to fabricate and characterise poly(ethylene) oxide (PEO) nanofibres with different concentrations for cytotoxicity evaluation in human breast cancer cell lines (MCF-7) and to get an optimal PEO nanofibre concentration (permissible limit) as a suitable polymer matrix or carrier with potential use in diagnostic applications. The fabrication of PEO nanofibres was done using electrospinning and was characterised by structure and morphology, surface roughness, chemical bonding and release profiles. The functional effects of PEO nanofibres were evaluated with MTS assay and colony formation assay in MCF-7 cells. The results showed that viscosity plays a vital role in synthesising a polymer solution in electrospinning for producing beadless nanofibrous mats ranging from 4.7 Pa·s to 77.7 Pa·s. As the PEO concentration increases, the nanofibre diameter and thickness will increase, but the surface roughness will be decreased. The average fibre diameter for 5 wt% PEO, 6 wt% PEO and 7 wt% PEO nanofibres were 129 ± 70 nm, 185 ± 55 nm and 192 ± 53 nm, respectively. In addition, the fibre thickness for 4 wt% PEO, 5 wt% PEO, 6 wt% PEO and 7 wt% PEO nanofibres were 269 ± 3 μm, 664 ± 4 μm, 758 ± 7 μm and 1329 ± 44 μm, respectively. Contrarily, the surface roughness for 4 wt% PEO, 5 wt% PEO, 6 wt% PEO and 7 wt% PEO nanofibres were 55.6 ± 9 nm, 42.8 ± 6 nm, 42.7 ± 7 nm and 36.6 ± 1 nm, respectively. PEO nanofibres showed the same burst release pattern and rate due to the same molecular weight of PEO with a stable release rate profile after 15 min. It also demonstrates that the percentage of PEO nanofibre release increased with the increasing PEO concentration due to the fibre diameter and thickness. The findings showed that all PEO nanofibres formulations were non-toxic to MCF-7 cells. It is suggested that 5 wt% PEO nanofibre exhibited non-cytotoxic characteristics by maintaining the cell viability from dose 0-1000 μg/ml and did not induce the number of colonies. Therefore, 5 wt% PEO nanofibre is the optimal nanofibre concentration and was suggested as a suitable base polymer matrix or carrier with potential use for diagnostic purposes. The findings in this study have demonstrated the influence of cell growth and viability, including the effects of PEO nanofibre formulations on cancer progress characteristics to achieve a permissible PEO nanofibre concentration limit that can be a benchmark in medical applications, particularly diagnostic applications.
Sensors play a significant role in modern technologies and devices used in industries, hospitals, healthcare, nanotechnology, astronomy, and meteorology. Sensors based upon nanostructured materials have gained special attention due to their high sensitivity, precision accuracy, and feasibility. This review discusses the fabrication of graphene-based biosensors and gas sensors, which have highly efficient performance. Significant developments in the synthesis routes to fabricate graphene-based materials with improved structural and surface properties have boosted their utilization in sensing applications. The higher surface area, better conductivity, tunable structure, and atom-thick morphology of these hybrid materials have made them highly desirable for the fabrication of flexible and stable sensors. Many publications have reported various modification approaches to improve the selectivity of these materials. In the current work, a compact and informative review focusing on the most recent developments in graphene-based biosensors and gas sensors has been designed and delivered. The research community has provided a complete critical analysis of the most robust case studies from the latest fabrication routes to the most complex challenges. Some significant ideas and solutions have been proposed to overcome the limitations regarding the field of biosensors and hazardous gas sensors.
Cancer at the lower end of the digestive tract, colorectal cancer (CRC), starts with asymptomatic polyps, which can be diagnosed as cancer at a later stage. It is the fourth leading cause of malignancy-associated mortality worldwide. Despite progress in conventional treatment strategies, the possibility to overcome the mortality and morbidity issues with the enhancement of the lifespan of CRC patients is limited. With the advent of nanocarrier-based drug delivery systems, a promising revolution has been made in diagnosis, treatment, and theranostic purposes for cancer management. Herein, we reviewed the progress of miniaturized nanocarriers, such as liposomes, niosomes, solid lipid nanoparticles, micelles, and polymeric nanoparticles, employed in passive and active targeting and their role in theranostic applications in CRC. With this novel scope, the diagnosis and treatment of CRC have proceeded to the forefront of innovation, where specific characteristics of the nanocarriers, such as processability, flexibility in developing precise architecture, improved circulation, site-specific delivery, and rapid response, facilitate the management of cancer patients. Furthermore, surface-engineered technologies for the nanocarriers could involve receptor-mediated deliveries towards the overexpressed receptors on the CRC microenvironment. Moreover, the potential of clinical translation of these targeted miniaturized formulations as well as the possible limitations and barriers that could impact this translation into clinical practice were highlighted. The advancement of these newest developments in clinical research and progress into the commercialization stage gives hope for a better tomorrow.
Cancer has become a major public health issue leading to one of the foremost causes of morbidity and death in the world. Despite the current advances in diagnosis using modern technologies and treatment via surgery or chemo- and radio-therapies, severe side effects or after-effects limit the application of these treatment modalities. Novel drug delivery systems have shown the potential to deliver chemotherapeutics directly to cancer cells, thus minimizing unnecessary exposure to healthy cells. Concurrently, to circumvent difficulties associated with conventional deliveries of cancer therapeutics, natural polysaccharides have gained attention for the fabrication of such deliveries owing to biocompatibility, low toxicity, and biodegradability. It has been exhibited that natural polysaccharides can deliver high therapeutic concentrations of the entrapped drug to the target cells by sustained and targeted release. Considering the immense potential of natural polymers, the present work focuses on naturally generated biopolymer carriers based on chitosan and hyaluronic acid. This review delineated on the role of chitosan and its derivation from renewable resources as a biocompatible, biodegradable, nonimmunogenic material with notable antitumor activity as a drug delivery carrier in oncotherapy. Moreover, hyaluronic acid, itself by its structure or when linked with other molecules contributes to developing promising pharmaceutical delivery systems to setback the restrictions related to conventional cancer treatment.
Eco-friendly nanotechnology-enabled biopolymers are one of the novel concepts of packaging materials to substitute traditional synthetic polymers and their composites. This article succinctly reviews the recent developments of introducing additional functionalities to biopolymers using metal and metal oxide nanoparticles. The functionality of metal nanoparticles such as silver, zinc oxide, titanium dioxide, copper oxide, gold, and magnesium oxide, as food packaging materials were discussed. The addition of nanoparticles in biopolymers improves mechanical properties, gas barrier properties, durability, temperature stability, moisture stability, antimicrobial activity, antioxidant property, and UV absorbance and can prevent the presence of ethylene and oxygen, hence extending the shelf life of foodstuffs. Other than this, the functional activity of these biopolymer composite films helps them to act like smart or intelligent packaging. The selection of metal nanoparticles, particle migration, toxicological effect, and potential future scope in the food packaging industry are also reviewed.
This review delves into the utilization of intermetallic alloys (IMAs) as advanced biomaterials for medical implants, scrutinizing their conceptual framework, fabrication challenges, and diverse manufacturing techniques such as casting, powder metallurgy, and additive manufacturing. Manufacturing techniques such as casting, powder metallurgy, additive manufacturing, and injection molding are discussed, with specific emphasis on achieving optimal grain sizes, surface roughness, and mechanical properties. Post-treatment methods aimed at refining surface quality, dimensional precision, and mechanical properties of IMAs are explored, including the use of heat treatments to enhance biocompatibility and corrosion resistance. The review presents an in-depth examination of IMAs-based implantable biomaterials, covering lab-scale developments and commercial-scale implants. Specific IMAs such as Nickel Titanium, Titanium Aluminides, Iron Aluminides, Magnesium-based IMAs, Zirconium-based IMAs, and High-entropy alloys (HEAs) are highlighted, with detailed discussions on their mechanical properties, including strength, elastic modulus, and corrosion resistance. Future directions are outlined, with an emphasis on the anticipated growth in the orthopedic devices market and the role of IMAs in meeting this demand. The potential of porous IMAs in orthopedics is explored, with emphasis on achieving optimal pore sizes and distributions for enhanced osseointegration. The review concludes by highlighting the ongoing need for research and development efforts in IMAs technologies, including advancements in design and fabrication techniques.