The use of nanotechnology has the potential to revolutionize the detection and treatment of cancer. Developments in protein engineering and materials science have led to the emergence of new nanoscale targeting techniques, which offer renewed hope for cancer patients. While several nanocarriers for medicinal purposes have been approved for human trials, only a few have been authorized for clinical use in targeting cancer cells. In this review, we analyze some of the authorized formulations and discuss the challenges of translating findings from the lab to the clinic. This study highlights the various nanocarriers and compounds that can be used for selective tumor targeting and the inherent difficulties in cancer therapy. Nanotechnology provides a promising platform for improving cancer detection and treatment in the future, but further research is needed to overcome the current limitations in clinical translation. Graphical Abstract

Indole derivatives have become an important class of compounds in medicinal chemistry, recognized for their wide-ranging biological activities and therapeutic potential. This review provides a comprehensive overview of recent advances in the evaluation of indole-based compounds in the last five years, highlighting their roles in cancer treatment, infectious disease management, anti-inflammatory therapies, metabolic disorder interventions, and neurodegenerative disease management. Indole derivatives have shown significant efficacy in targeting diverse biological pathways, making them valuable scaffolds in designing new drugs. Notably, these compounds have demonstrated the ability to combat drug-resistant cancer cells and pathogens, a significant breakthrough in the field, and offer promising therapeutic options for chronic diseases such as diabetes and hypertension. By summarizing recent key findings and exploring the underlying biological mechanisms, this review underscores the potential of indole derivatives in addressing major healthcare challenges, thereby instilling hope and optimism in the field of modern medicine.

The present study focuses on the antibacterial activity of ZnO nanoparticles, evaluating variations based on morphology. Interest in ZnO nanoparticles arises from their high surface-to-volume ratio that enables effective interaction with bacterial cells. Their antibacterial properties depend on size and nanostructure, with enhanced activity attributed to increased surface area, promoting maximum contact with microbial membranes, cellular damage, and growth inhibition. Zinc oxide (ZnO) nanoparticles with two distinct shapes—ellipsoidal nanorods (Z1) and 3D microspheres (Z2)—were synthesized using a simple, template-free aqueous precipitation method. Zinc nitrate and hexamethylenetetramine (HMT) served as starting materials. The nanoparticles were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA). The point of zero charge (PZC) was determined by the salt addition method. SEM images showed that particle shape changed with reaction time. XRD confirmed a hexagonal wurtzite crystal structure, with average crystallite sizes of 22.09 nm for Z1 and 27.18 nm for Z2. FT-IR spectra showed Zn–O bond vibrations between 540 and 411 cm⁻¹. Antibacterial activity was evaluated using the agar well diffusion method against Gram-positive (Streptococcus mutans, Staphylococcus aureus) and Gram-negative (Escherichia coli, Enterobacter cloacae) bacteria. The synthesized ZnO nanoparticles exhibited significantly higher antibacterial effects than commercial ZnO, which showed no activity at tested concentrations (0.25, 0.50, and 0.75 µg/µL). At 0.75 µg/µL, Z1 nanorods produced inhibition zones of 30 mm (E. coli), 28 mm (E. cloacae), 28 mm (S. mutans), and 30 mm (S. aureus). Z2 microspheres showed even stronger effects: 35 mm, 32 mm, 30 mm, and 31 mm, respectively. These findings demonstrate the superior antibacterial properties of the synthesized ZnO nanoparticles, particularly the 3D microspheres, highlighting their potential in antimicrobial coatings and biomedical applications.