Bovine serum albumin functionalized blue emitting Ti3 C2 MXene Quantum Dots as a sensitive fluorescence probe for Fe3+ ions detection and its toxicity analysis

The potential of MXene-based materials in fluorescence-based sensing/biosensing of ionic and organic contaminants in environment and food samples: Recent advancements and challenges

MXenes belong to one of the recently developed advanced materials with tremendous potential for diverse sensing applications. To date, various types of MXene-based materials have been developed to generate direct/indirect ultrasensitive sensing signals against various forms of analytes via fluorescence quenching or enhancement. In this work, the fluorescence sensing/biosensing capabilities of the MXene-based materials have been explored and evaluated against a list of ionic/emerging pollutants in environment and food matrices. The suitability of an MXene-based sensing approach is also validated through the assessment of the performance based on the basic quality assurance parameters, e.g., limit of detection (LOD), sensing range, and response time. Accordingly, the best performing MXene-based materials are selected and recommended for the given target(s) to help facilitate their scalable applications under real-world conditions.

Recent Advances in MXene Quantum Dots: A Platform with Unique Properties for General-Purpose Functional Materials with Novel Biomedical Applications

Developing new, high-performance materials is a prerequisite for technological advancement. In comparison to bulk materials, quantum dots have a number of good advantages due to their small size, high surface area, and quantum dimensions. Quantum dots, two-dimensional materials with lateral dimensions less than 100 nm, can be generated by the quantum confinement effect. Mxene quantum dots (MQDs) retain some of their two-dimensional characteristics. They also exhibit novel physicochemical properties, including enhanced dispersibility in aqueous and nonaqueous phases, modification or doping capabilities, and photoluminescence. MQDs, due to their unique and diverse properties, have been receiving a great deal of attention as new members of the Mxene group and wide use for biotechnology, bioimaging, optoelectronics, catalysis, cancer therapy, etc. This review aims to provide an overview of the synthesis of MQDs, their optical properties, and their cancer therapy applications. MQDs exhibit remarkable photothermal and photodynamic features and can be suitable for bioimaging. In addition to obtaining bioimaging, photothermal therapy (PTT) and photodynamic therapy (PDT) effects simultaneously, MQDs have high biocompatibility in vitro and in vivo, providing evidence of their potential clinical utility. Herein, recent developments and future prospects concerning MQDs biomedical applications are discussed.

Toxicity Study and Binding Analysis of Newly Synthesized Antifungal N-(4-aryl/cyclohexyl)-2-(pyridine-4-yl carbonyl) hydrazinecarbothioamide Derivative with Bovine Serum Albumin

The presence of the p-aryl/cyclohexyl ring in the N-(4-aryl/cyclohexyl)-2-(pyridine-4-yl carbonyl) hydrazine carbothioamide derivative (2C) is reported to enhance the antifungal properties when compared to those of itraconazole. Serum albumins present in plasma bind and transport ligands, including pharmaceuticals. This study explored 2C interactions with BSA using spectroscopic methods such as fluorescence and UV-visible spectroscopy. In order to acquire a deeper comprehension of how BSA interacts with binding pockets, a molecular docking study was carried out. The fluorescence of BSA was quenched by 2C via a static quenching mechanism since a decrease in quenching constants was observed from 1.27 × 10⁵ to 1.14 × 10⁵. Thermodynamic parameters indicated hydrogen and van der Waals forces responsible for the BSA-2C complex formation with binding constants ranging between 2.91 × 10⁵ and 1.29 × 10⁵, which suggest a strong binding interaction. Site marker studies displayed that 2C binds to BSA's subdomains IIA and IIIA. Molecular docking studies were conducted to further comprehend the molecular mechanism of the BSA-2C interaction. The toxicity of 2C was predicted by Derek Nexus software. Human and mammalian carcinogenicity and skin sensitivity predictions were associated with a reasoning level of equivocal, inferring 2C to be a potential drug candidate.

An Acid-triggered Reactive and Enhanced Fluorescent Probe for Selective Detection of Al3+/H+ and its Application in Real Water Samples and Living Cells

A reactive fluorescent "turn-on" probe (di-PIP) with imine-linked dual phenanthro[9,10-d]imidazole luminophore have been conveniently prepared as an Al³⁺ and H⁺ dual functional receptor. di-PIP displayed high selectivity and sensitivity towards Al³⁺ ion in DMF/HEPES accompanied by fluorescence blue-shift and a good linear relationship as well as a low detection limit of 30.5 nmol·L^-1, which can root from the synergetic functions of the decomposition reaction of di-PIP promoted by acidic Al³⁺ and the coordination effect between decomposition product and Al³⁺. Intriguingly, it was found that hydrogen ion H⁺ can be sufficient for simulating the fluorescence enhancing of di-PIP. ¹H NMR titration and MS analyses for elucidation of the intermediate structure further revealed that the acid-triggered decomposition reaction resulted in the rapid, and sensitive sensing to Al³⁺ and H⁺. In addition, the probe di-PIP could be successfully applied to the detection of Al³⁺ in real water samples, and also utilized to visualize Al³⁺ and H⁺ in the living cells.

Quantum Dots Compete at the Acme of MXene Family for the Optimal Catalysis

It is well known that two-dimensional (2D) MXene-derived quantum dots (MQDs) inherit the excellent physicochemical properties of the parental MXenes, as a Chinese proverb says, "Indigo blue is extracted from the indigo plant, but is bluer than the plant it comes from." Therefore, 0D QDs harvest larger surface-to-volume ratio, outstanding optical properties, and vigorous quantum confinement effect. Currently, MQDs trigger enormous research enthusiasm as an emerging star of functional materials applied to physics, chemistry, biology, energy conversion, and storage. Since the surface properties of small-sized MQDs include the type of surface functional groups, the functionalized surface directly determines their performance. As the Nobel Laureate Wolfgang Pauli says, "God made the bulk, but the surface was invented by the devil," and it is just on the basis of the abundant surface functional groups, there is lots of space to be thereof excavated from MQDs. We are witnessing such excellence and even more promising to be expected. Nowadays, MQDs have been widely applied to catalysis, whereas the related reviews are rarely reported. Herein, we provide a state-of-the-art overview of MQDs in catalysis over the past five years, ranging from the origin and development of MQDs, synthetic routes of MQDs, and functionalized MQDs to advanced characterization techniques. To explore the diversity of catalytic application and perspectives of MQDs, our review will stimulate more efforts toward the synthesis of optimal MQDs and thereof designing high-performance MQDs-based catalysts.

Smart MXene Quantum Dot-Based Nanosystems for Biomedical Applications

MXene quantum dots (QDs), with their unique structural, optical, magnetic, and electronic characteristics, are promising contenders for various pharmaceutical and biomedical appliances including biological sensing/imaging, cancer diagnosis/therapy, regenerative medicine, tissue engineering, delivery of drugs/genes, and analytical biochemistry. Although functionalized MXene QDs have demonstrated high biocompatibility, superb optical properties, and stability, several challenging issues pertaining to their long-term toxicity, histopathology, biodistribution, biodegradability, and photoluminescence properties are still awaiting systematic study (especially the move towards the practical and clinical phases from the pre-clinical/lab-scale discoveries). The up-scalable and optimized synthesis methods need to be developed not only for the MXene QD-based nanosystems but also for other smart platforms and hybrid nanocomposites encompassing MXenes with vast clinical and biomedical potentials. Enhancing the functionalization strategies, improvement of synthesis methods, cytotoxicity/biosafety evaluations, enriching the biomedical applications, and exploring additional MXene QDs are crucial aspects for developing the smart MXene QD-based nanosystems with improved features. Herein, recent developments concerning the biomedical applications of MXene QDs are underscored with emphasis on current trends and future prospects.