A carboethoxy quinoline-Derived Schiff base chemosensor: Crystal structure, selective Hg2+ ion detection and its computational study.

Environmental monitoring of mercury (Hg2+) ions has become increasingly important as a result of their detrimental effects on biological organisms at all levels. To recognize toxic metal ions, utmost effort has been devoted to developing new materials that are highly selective, ultra-sensitive, and provide rapid response. In this context, a new chemosensor, 2-imino [N - (N-amido phenyl)]-6-methoxy-3-carbethoxy quinoline (L), has been synthesized by combining 2-formyl-6-methoxy-3-carbethoxy quinoline and benzhydrazide and it has been extensively characterized by NMR, FTIR, ESI-Mass and SCXRD analysis. Probe L has excellent specificity and sensitivity toward Hg2+ ions in semi-aqueous solutions, with a detection limit of 0.185 µM, regardless of the presence of other interfering cations. Chromogenic behavior was demonstrated by the L when it changed the color of the solution from colorless to light yellow, a change that can be observed visually. The probe L forms a 1:1 stochiometric complex with an estimated association constant (Ka) of 6.74 × 104 M-1. The 1H NMR change and density functional theory calculations were analyzed to improve our understanding of the sensing mechanism. Also, an inexpensive and simple paper-based test kit has been developed for the on-site detection of mercury ions in water samples.

Fastidious Anatomization of Biota Procured Compounds on Cancer Drug Discovery.

BACKGROUND: Natural products are the rootstock for identifying new drugs since ancient times. In comparison with synthetic drugs, they have abounding beneficial effects in bestowing protection against many diseases, including cancer. Cancer has been observed as a major threat in recent decades, and its prevalence is expected to increase over the next decades. Also, current treatment methods in cancer therapy such as radiation therapy and chemotherapy cause severe adverse side effects among the cancer population. Therefore, it is exigent to find a remedy without any side effects. METHODS: In recent years, research has focused on obtaining naturally derived products to encounter this complication. The current pace of investigations, such as gene identification and advancement in combinatorial chemistry, leads to the aberrant access to a wide range of new synthetic drugs. In fact, natural products act as templates in structure predictions and synthesis of new compounds with enhanced biological activities. RESULTS: Recent developments in genomics have established the importance of polymorphism, which implies that patients require different drugs for their treatment. This demands the discovery of a large number of drugs, but limited sources restrict the pharmaceutical industry to overcome these major obstacles. The use of natural products and their semisynthetic and synthetic analogues could alleviate these problems. However, the lack of standardization in terms of developing methods for evaluating the chemical composition, efficacy, isolation and international approval is still a major limitation in this field. In the past few years, several drug-approval authorities, including the FDA and WHO have allowed using these naturally derived compounds in humans. CONCLUSION: In this review, we described the use of some natural products from plant and marine sources in cancer treatment and shed some light on semi-synthetic and synthetic compounds derived from natural sources used in cancer therapy.

Pineapple Peel-Derived Carbon Dots: Applications as Sensor, Molecular Keypad Lock, and Memory Device.

Herein, the fluorescent carbon dots (CDs) with blue emission were prepared by hydrothermal treatment using pineapple peel as a source of carbon. The as-prepared CDs exhibited turn-Off fluorescence behavior toward Hg2+ and subsequent turn-On behavior for l-cysteine along with enhanced biocompatibility and negligible cytotoxicity for cell imaging. The practical applicability of carbon dots was used for the quantification of Hg2+ in water. On the basis of the spectral characteristic changes, we have designed individual elementary logic operations such as NOT and IMP gates, by utilizing CD as probe and Hg2+ and l-Cys as chemical inputs. We have also demonstrated the utility of this system in electronic security devices and as memory element, with the idea of the switching.