Water contamination due to the presence of lead is one of the leading causes of environmental and health hazards because of poor soil and groundwater waste management. Herein we report the synthesis of functionally modified luminescent carbon quantum dots (CQDs) obtained from watermelon juice as potential nanomaterials for the detection of toxic Pb2+ ions in polluted water and cancer cells. By introducing surface passivating ligands such as ethanolamine (EA) and ethylenediamine (ED) in watermelon juice, watermelon-ethanolamine (WMEA)-CQDs and watermelon-ethylenediamine (WMED)-CQDs exhibited a remarkable ~10-fold and ~6-fold increase in fluorescence intensity with respect to non-doped WM-CQDs. The relative fluorescence quantum yields of WMEA-CQDs and WMED-CQDs were found to be 8% and 7%, respectively, in an aqueous medium. Among various functionally-modified CQDs, only WMED-CQDs showed high selectivity towards Pb2+ ions with a remarkably good limit of detection (LoD) of 190 pM, which is less than that of the permissible limit (72 nM) in drinking water. The functionally altered WMED-CQDs detected Pb2+ metal ions in polluted water and in a human cervical cancer cell line (HeLa), thus advocating new vistas for eco-friendly nanomaterials for their use as diagnostic tools in the environment and biomedical research areas.
Ophthalmic diseases can result in permanent vision loss and blindness. Convenient topical and systemic treatments are preferred to address these sight-threatening conditions. However, the unique anatomy of the eye presents challenges for drug delivery. Various ophthalmic ointment formulations have been developed to enhance bioavailability in the eye to prolong residence time and improve corneal permeability. This article explores a wide range of ocular diseases affecting individuals globally and how ointments are used to manage them. From eye to ocular barriers, this review focuses on published scientific research and formulation strategies for severe ocular complications using conventional topical ointments. Additionally, it delves through patented technologies and marketed formulations supporting the use of ointments in ocular drug delivery.
The pursuit of sustainable and environmentally benign energy storage solutions has propelled significant interest in organic batteries, which utilize redox-active organic compounds as electrode materials. A pivotal component in determining their electrochemical performance, safety, and long-term stability is the electrolyte. Polymer-based electrolytes (PBEs) have emerged as promising candidates owing to their intrinsic advantages, such as enhanced thermal stability, mechanical integrity, and the mitigation of leakage and flammability risks associated with conventional liquid electrolytes. Unlike previous reviews that broadly cover solid electrolytes, this review specifically focuses on the unique developments of polymer-based electrolytes tailored for organic batteries over the past few years. This review presents a comprehensive overview of the recent progress in PBEs specifically designed for organic battery systems. It systematically examines various categories, including solid polymer electrolytes (SPEs), valued for their structural simplicity and stability; gel polymer electrolytes (GPEs), noted for their high ionic conductivity and processability; and polymer-inorganic composite electrolytes, which synergistically integrate the mechanical flexibility of polymers with the ionic conductivity of inorganic fillers. Additionally, the review delves into the latest advancements in ionogels and poly(ionic liquid) electrolytes, highlighting their potential to overcome existing limitations and enable next-generation battery performance. The article concludes with a critical discussion on prevailing challenges and prospective research directions, emphasizing the importance of advanced material design, interfacial engineering, and sustainable synthesis approaches to facilitate the practical realization of high-performance organic batteries.