Nanoparticles are molecular-sized solids with at least one dimension measuring between 1-100 nm or 10-1000 nm depending on the individual discipline's perspective. They are aggregates of anywhere from a few hundreds to tens of thousands of atoms which render them larger than molecules but smaller than bulk solids. Consequently, they frequently exhibit physical and chemical properties somewhere between. On the other hand, nanocrystals are a special class of nanoparticles which have started gaining attention recently owing to their unique crystalline structures which provide a larger surface area and promising applications including chiral separations. Hybrid nanoparticles are supported by the growing interest of chemists, physicists, and biologists, who are researching to fully exploit them. These materials can be defined as molecular or nano-composites with mixed (organic or bio) and inorganic components, where at least one of the component domain has a dimension ranging from a few Å to several nanometers. Similarly, and due to their extraordinary physical, chemical, and electrical properties, single-walled carbon nanotubes have been the subject of intense research. In this short review, the focus is mainly on the current well-established simple preparation techniques of chiral organic and hybrid nanoparticles as well as single-walled carbon nanotubes and their applications in separation science. Of particular interest, cinchonidine, chitosan, and β-CD-modified gold nanoparticles (GNPs) are discussed as model examples for organic and hybrid nanoparticles. Likewise, the chemical vapor deposition method, used in the preparation of single-walled carbon nanotubes, is discussed. The enantioseparation applications of these model nanomaterials is also presented.

High concentrations of the most consumed pharmaceuticals, caffeine and paracetamol, have been observed globally in wastewater treatment plant discharge. Here, we assess the potential for photodegradation of caffeine and paracetamol residues at concentrations like those observed in treated wastewater discharges to the environment. Laboratory assays were used to measure rates of photodegradation of these two compounds both in distilled water and in natural river water with leaf litter leachate. When exposed to artificial light simulating natural sunlight, the half‐life values of caffeine and paracetamol were significantly shorter than in the dark. The presence of organic matter increased caffeine and paracetamol half‐life by lessening the photolytic effect. These results suggest that photolysis is a substantial contributor to the degradation of caffeine and paracetamol. The findings contribute to our understanding of persistence of pharmaceuticals in treated wastewater discharge.Practitioner Points The photodegradation of caffeine and paracetamol residues in surface water was examined. With leaf litter leachate, caffeine and paracetamol were photodegraded in distilled and natural river water in laboratory. Caffeine's half‐life ranged from 2.3 to 16.2 days under artificial sunlight andparacetamols from 4.3 to 12.2 days. When incubated in the dark, the half‐life for both compounds exceeded 4 weeks. Organic matter decreased the photolytic action of caffeine and paracetamol.