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NSET-based multiplex biosensor was demonstrated. The NSET pairs of UCNP/Au nanourchins and QD/Au nanorods ensured a highly sensitive, facile, and simultaneous screen of foodborne bacterial pathogens, S. typhimurium and E. coli, in a single pot.

Thermoplastic polyurethane-silver nanocomposites (PU-Ag NCs) have considerable potential in many medical applications due to their superior mechanical and antimicrobial properties. Herein, a microwave-promoted flow system is successfully employed for continuous in situ manufacturing of PU NCs having spherical silver nanoparticles (AgNPs) without any reducing agent at similar to 40 degrees C in approximately 4 minutes. The main experimental parameters, including microwave power, metal salt concentration, polymer concentration, and flow rate, are optimised for the reproducible synthesis of AgNPs (similar to 5 nm) in the PU matrix, characterised by HRTEM-EDS and DLS analysis. XRD patterns indicate an increase in PU crystallinity with decreased particle size. Conventional heating flow synthesis at similar to 50 degrees C or microwave-batch synthesis (MWB) at similar to 44 and similar to 50 degrees C is ineffective in preparing AgNPs, and only large AgNPs (>100 nm) are synthesised at 70 degrees C in the MWB reactor. PU-Ag NC films bearing small AgNPs (similar to 5 nm) exhibit superior antibacterial activity (>97%) against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus compared to large NPs (similar to 218 nm). The proposed method may manufacture other metal-polymer matrix composites.

Continuous manufacturing of pure nanocrystals with a narrow size distribution in a polymer matrix is very challenging, although it is highly crucial to get their full potential for advanced applications. A long-lasting nanocomposite (NC) manufacturing challenge is, for the first time, overcome by a microwave-powered fluidic system (MWFS). The effect of microwave power (MWP), flow rate, and the concentration of the reagents are systematically studied. The nylon-6 NC bearing evenly distributed silver nanoparticles (AgNPs) with a mean size of similar to 2.59 +/- 0.639 nm is manufactured continuously in similar to 2 min at similar to 50-55 degrees C using a green solvent, formic acid. The AgNP size becomes smaller when increasing the polymer concentration gradually. Small NPs with a narrow size distribution are produced at high MWP (40 W), but large ones with a broad size distribution at low MWP (10 W). The nylon-6 crystallinity is NP size-dependent, and the gamma-phase (pseudo-hexagonal crystal) is dominant in the presence of small NPs as against the large counterparts. Given the small-sized AgNPs in the MWF-manufactured NCs, the antibacterial activity tests with Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa show superior activity compared to that of the large AgNP-bearing (similar to 50 nm) NCs produced in a conventional heating fluidic system. The proposed MWFS can manufacture other added-value NCs continuously.

Green synthesis of metallic nanoparticles (NPs) is acquiring considerable attention due to its environmental and economic superiorities over other methods. This study describes the practical synthesis of silver nanoparticles (AgNPs) through the reduction of silver nitrate solution using an algal source, Chlorella vulgaris, as the reducing as well as the stabilizing agent. The energy required for this synthesis was supplied by microwave radiation. The ultraviolet-visible spectroscopy exhibited a single peak related to the surface plasmon absorbance of AgNPs at 431 nm. The AgNPs with high stability (a zeta potential of −17 mV), hydrodynamic size distribution of 1–50 nm, and mostly spherical shape were obtained through a 10 min process. Fourier transform infrared spectroscopy analysis revealed that several functional groups, including carbonyl groups of C. vulgaris, play a significant role in the formation of functional NPs. Antibacterial features of the produced AgNPs were verified against those of Salmonella enterica subsp. enterica serovar typhimurium and Staphylococcus aureus, demonstrating a considerable growth inhibition at increasing concentrations of the NPs. As a result, the formed AgNPs can be used as a promising agent against bacterial diseases.

Water quality assessment is vital to identify existing problems and any changes that emerge in water sources over a period of time. Conventional water quality monitoring systems remain to be limited to on-site sample collection and further analysis in environmental laboratories. The progress in Arduino-based low-cost and open-source hardware has paved the way for the development of low-cost, portable, and on-site measuring platforms. In this work, we have assembled an Arduino-based open-source water testing platform out of commercially available sensors and controllers. The water testing system was powered by a 9 V battery and had the capability of measuring water turbidity, acidity, and temperature on-site in real-time. The calibration and validation studies were carried out to assess the measurement capabilities of turbidity and pH sensors in the lab using calibration samples and UV-Vis-NIR absorption spectroscopy. The water quality platform was tested in an artificial lake that is located at Sabanci University Campus (Istanbul, Turkey), which serves as a reservoir for treated wastewaters and rainwater. Untreated wastewater samples were collected from the wastewater treatment station of the university for comparison. The measurements performed on several locations along the coast of the artificial lake were also validated in the laboratory. The water testing platform showed significant potential for miniaturization and portability of such analytical platforms for on-site environmental monitoring.

Drug-loaded nanoparticles have many advantages in drug administration, which is an essential step for the impact of the drugs and their mechanism of action. Circular dichroism (CD) is a spectroscopy technique that measures the absorbance difference between right-circularly polarized light and left-circularly polarized light. Of several analytical techniques available, Fourier transform infrared spectroscopy is a powerful and widely employed technique explicitly for identifying chemical species. The peaks in the IR spectrum of a sample represent the molecular vibrations of the molecules present in the sample, signifying the various chemical bonds and functional groups. Various types of nanoparticles are being utilized for drug delivery applications because of their advantages such as controlled drug release, protection of the therapeutic payload, improved bioavailability, and targeted delivery. The discovery of novel nanoparticles and their application to the diagnosis and treatment of diseases have received considerable attention during the past decades.

Microwave-promoted continuous flow systems have emerged as a game-changer in nanoparticle synthesis. Owing to the excellent compatibility between fast, sustainable microwave heating and one-step, efficient flow chemistry, this promising technology is meant to enhance the synthetic abilities of nanoscientists. This Perspective aims to present a panoramic view of the state of the art in this field. Additionally, the effect of various microwave and flow parameters on the properties of nanoparticles is discussed along with a comparative glance at the features that make flow reactors more practical and sustainable than their batch counterparts. The overview has also analyzed various microwave continuous flow reactors available in the literature, with an acute emphasis on the nanosynthesis route and design features. Moreover, a discussion on the numerical modeling of microwave flow systems has been made a part of this perspective to reiterate its significance and encourage research in this domain. The Perspective also briefly comments on existing challenges and future prospects of this technology.

The similarity between originator and biosimilar monoclonal antibody candidates are rigorously assessed based on primary, secondary, tertiary, quaternary structures, and biological functions. Minor differences in such parameters may alter target-binding, potency, efficacy, or half-life of the molecule. The charge heterogeneity analysis is a prerequisite for all biotherapeutics. Monoclonal antibodies are prone to enzymatic or non-enzymatic structural modifications during or after the production processes, leading to the formation of fragments or aggregates, various glycoforms, oxidized, deamidated, and other degraded residues, reduced Fab region binding activity or altered FcR binding activity. Therefore, the charge variant profiles of the monoclonal antibodies must be regularly and thoroughly evaluated. Comparative structural and functional analysis of physically separated or fractioned charged variants of monoclonal antibodies has gained significant attention in the last few years. The fraction-based charge variant analysis has proved very useful for the biosimilar candidates comprising of unexpected charge isoforms. In this report, the key methods for the physical separation of monoclonal antibody charge variants, structural and functional analyses by liquid chromatography-mass spectrometry, and surface plasmon resonance techniques were reviewed.

A facile and green synthesis of silver nanoparticles (AgNPs) by aqueous chitosan solution and microwave irradiation is proposed as a cost effective and environmentally benevolent alternative to chemical and physical methods. With this aim, different amounts of chitosan solution (3–9 ml) with several concentration (4–6% w/v) and 3 ml of the silver salt solution (0.5% w/v) were mixed and microwave irradiated for 100 s. Response surface methodology (RSM) was used to evaluate the effects of the amount and concentration of chitosan solution on the particle size and concentration of the synthesized AgNPs. The optimum AgNPs synthesis process was obtained using 9 ml of 0.4% (w/v) chitosan solution. The spherical and more stable AgNPs synthesized at optimum conditions had particle size, concentration, polydispersity index (PDI) and zeta potential values of 37 nm, 69 ppm, 0.557 and +50 mV, respectively. The synthesized AgNPs indicated strong antifungal activity toward Aspergillus flavus and high antibacterial activity against both Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli).

Fluorescence resonance energy transfer, one of the most powerful phenomena for elucidating molecular interactions, has been extensively utilized as a biosensing tool to provide accurate information at the nanoscale. Numerous aptamer- and nanomaterial-based FRET bioassays has been developed for detection of a large variety of molecules. Affinity probes are widely used in biosensors, in which aptamers have emerged as advantageous biorecognition elements, due to their chemical and structural stability. Similarly, optically active nanomaterials offer significant advantages over conventional organic dyes, such as superior photophysical properties, large surface-to-volume ratios, photostability, and longer shelf life. In this report (with 175 references), the use of aptamer-modified nanomaterials as FRET couples is reviewed: quantum dots, upconverting nanoparticles, graphene, reduced graphene oxide, gold nanoparticles, molybdenum disulfide, graphene quantum dots, carbon dots, and metal-organic frameworks. Tabulated summaries provide the reader with useful information on the current state of research in the field. Graphical abstract Schematic representation of a fluorescence resonance energy transfer-based aptamer nanoprobe in the absence and presence of a given target molecule (analyte). Structures are not drawn to their original scales.

Graphitic carbon nitride (g‐C3N4) is a metal‐free semiconductor that has been widely regarded as a promising candidate for sustainable energy production or storage. In recent years, g‐C3N4 has become the center of attention by virtue of its impressive properties, such as being inexpensive, easily fabricable, nontoxic, highly stable, and environment friendly. Herein, the recent research developments related to g‐C3N4 are outlined, which sheds light on its future prospective. Various synthetic methods and their impact on the properties of g‐C3N4 are detailed, along with discussion on frequently used characterization methods. Different approaches for g‐C3N4 surface functionalization, mainly categorized under covalent and noncovalent strategies, are outlined. Moreover, the processing methods of g‐C3N4, such as g‐C3N4‐based thin films, hierarchical, and hybrid structures, are explored. Next, compared with the extensively studied energy‐related applications of the modified g‐C3N4s, relatively less‐examined areas, such as environmental and sensing, are presented. By highlighting the strong potential of these materials and the existing research gaps, new researchers are encouraged to produce functional g‐C3N4‐based materials using diverse surface modification and processing routes.