Lucian-Gabriel Zamfir

The integration of enzyme-loaded polymeric matrices with carbon-based nanomaterials and metallic nanoparticles into wearable multisensing patches, coupled with miniaturized portable detection devices, enables real-time, highly sensitive, and simultaneous monitoring of key clinical biomarkers (e.g., glucose, lactate, and H₂O₂) in clinical and point-of-care applications. Multiplex biosensors were fabricated by modifying screen-printed carbon paste electrodes (SPEs) with different composite nanomaterials based on carbon nanomaterials such as multi-walled carbon nanotubes (MWCNTs), single-walled carbon nanotubes (SWCNTs), or fullerenol (FL), the redox mediator Prussian Blue, and platinum nanoparticles (PtNPs). Chitosan and sol–gel polymer matrices were used to immobilize the enzymes glucose oxidase (GOx) and lactate oxidase (LOx), thus ensuring not only increased sensitivity and operational stability, but also high specificity for biomarker detection (glucose and lactate). Among the nanomaterials used for the development of multiplex biosensors, the SWCNT-PtNP composite was highlighted by electrochemical studies as having a significantly superior electrocatalytic activity toward the reduction of H₂O₂. This reaction occurs at a low applied potential of only −0.2 V vs. Ag/AgCl, achieving a specific sensitivity of 224.6 mA·M⁻¹·cm⁻², over a concentration range of 0.07 to 28.26 mM, and a detection limit of 3.2 μM. When functionalized with enzymes, SWCNT-PtNP-based biosensors exhibit improved conductivity, allowing the detection of glucose and lactate at a potential of −0.05 V vs. Ag/AgCl. The specific sensitivities obtained are 20.25 mA·M⁻¹·cm⁻² for glucose and 94.76 mA·M⁻¹·cm⁻² for lactate, and the corresponding detection limits are 23.6 μM and 5.0 μM, respectively. Finally, a wearable patch integrating the multiplex (bio)sensor with a portable potentiostat enabled simultaneous, sensitive, and selective detection of glucose, lactate, and H₂O₂ in sweat samples.

Decades of technological advancements have led to major environmental concerns, particularly the bioaccumulation of heavy metals, which pose persistent risks to ecosystems and human health. Consequently, research has increasingly shifted from conventional remediation techniques toward more sustainable, environmentally friendly solutions. This review explores recent advancements, ongoing challenges, and future perspectives in the field of bioremediation, emphasizing its potential as a green technology for heavy metal decontamination. Despite significant progress, key challenges remain, including scalability limitations and the management of bioremediation by-products, along with the influence of regulatory policies and public perception on its large-scale implementation. Emerging approaches such as genetic engineering and nanotechnology show promise in overcoming these limitations. Gene editing allows the tailoring of specific metabolic traits for bioprocesses targeted towards increased tolerance to pollutants and higher biodegradation efficiency, higher enzymatic specificity and affinity, and improved yield and fitness in plants. Nanotechnologies, particularly biogenic nanostructures, open up the possibility of repurposing waste materials as well as harnessing the advantages of the biosynthesis of NPs with higher stability, biocompatibility, and biostimulant capacities. Furthermore, biopolymers and bio-based nanocomposites can improve the efficiency and costs of bioremediation protocols. Even so, further research is essential to evaluate their long-term risks and feasibility.

The green synthesis of metal nanoparticles has received substantial attention due to their applications in various domains. The aim of the study was to obtain silver nanoparticles (AgNPs) by green synthesis with filamentous fungi, such as Cladosporium cladosporoides, Penicillium chrysogenum, and Purpureocillium lilacinum. Fungal species were grown on nutrient media and aqueous mycelium extracts were used to reduce Ag⁺ to Ag (0). The silver nanoparticles were analyzed by various techniques, such as UV-Visible spectroscopy (UV-Vis), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), and Zeta potential. The formation of silver nanoparticles was confirmed by UV-Vis spectroscopy and the color change of the mixture containing metal precursor and aqueous mycelium extract. FTIR displayed different functional groups as capping and reducing agents for the biosynthesis of AgNPs. SEM and TEM provided information on the particles’ morphology. DLS diagrams indicated mean particle diameters in the 124–168 nm region. All biosynthesized AgNPs had negative zeta values, which is a sign of good stability. Silver nanoparticles were evaluated for antimicrobial activity, and the most active were those synthesized with metabolites from Cladosporium, leading to 93.75% inhibition of Staphylococcus aureus, 67.20% of Escherichia coli, and 69.56% of Candida albicans. With the highest microbial inhibition percentage and a very good Poly Dispersion Index (Pd I), Cladosporium cladosporoides was selected as an environmentally friendly source of silver nanoparticles that could be used as a potential antimicrobial agent.

Contamination of soil with heavy metals has become a matter of global importance due to its impact on agriculture, environmental integrity, and therefore human health and safety. Several microbial strains isolated from soil contaminated by long-term chemical and petrochemical activities were found to manifest various levels of tolerance to Cr, Pb, and Zn, out of which Bacillus marisflavi and Trichoderma longibrachiatum exhibited above-moderate tolerance. The concentrations of target heavy metals before and after bioremediation were determined using electrochemical screen-printed electrodes (SPE) modified with different nanomaterials. The morpho-structural SEM/EDX analyses confirmed the presence of metal ions on the surface of the cell, with metal uptake being mediated by biosorption with hydroxyl, carboxyl, and amino groups as per FTIR observations. T. longibrachiatum was observed to pose a higher bioremediation potential compared to B. marisflavi, removing 87% of Cr and 67% of Zn, respectively. Conversely, B. marisflavi removed 86% of Pb from the solution, compared to 48% by T. longibrachiatum. Therefore, the fungal strain T. longibrachiatum could represent a viable option for Cr and Zn bioremediation strategies, whereas the bacterial strain B. marisflavi may be used in Pb bioremediation applications.

The tannery industry releases important amounts of chromium into the environment, its hexavalent form being highly toxic to all forms of life

Numerous economic and industrial activities release significant amounts of heavy metals into the environment, with varying levels of toxicity depending on the concentration of exposure

Nowadays, the rapid and easy determination of nitrite in the environment and foods represents a necessity since its chemical importance has been highlighted in many fields, especially in food and agriculture development

This paper presents a method for monitoring food freshness and quality through the early detection of biogenic amines, which are indicators of food spoilage/degradation. The urge to monitor food quality has led to a growing interest in the detection of toxic compounds, such as biogenic amines (BAs), as chemical indicators of food degradation by using different bioanalytical tools. The bioanalytical platform includes several parts and modules useful for food hazard evaluation. This paper presents how electrochemical and spectrometric detection works for biogenic amine monitoring in food and how the communication interface provides useful data.

Highly sensitive electrochemical biosensors for biogenic amine (BA) detection were developed using commercial screen-printed electrodes (SPEs) modified with a nanomaterial based on single-walled carbon nanotubes (SWCNT) and redox mediator, Prussian Blue (PB) and amine oxidase enzymes. The nanocomposite material enables an enhancement of the analytical performances for hydrogen peroxide detection, which represents the byproduct of the enzymatic oxidation of the BAs. The developed biosensors were integrated with a miniaturized potentiostate and a wireless data transfer interface in a portable system. The system was used for the detection of polyamines in soil solutions collected with a low-volume suction lysimeter.