Classical antibacterial drugs were designed to target specific bacterial properties distinct from host human cells to maximize potency and selectivity. These designs were quite effective as they could be easily derivatized to bear next-generation drugs. However, the rapid mutation of bacteria and their associated acquired drug resistance have led to the rise of highly pathogenic superbug bacterial strains for which treatment with first line drugs is no match. More than ever, there is a dire need for antibacterial drug design that goes beyond conventional standards. Taking inspiration by the body’s innate immune response to employ its own supply of labile copper ions in a toxic attack against pathogenic bacteria, which have a very low Cu tolerance, this review article examines the feasibility of Cu-centric strategies for antibacterial preventative and therapeutic applications. Promising results are shown for the use of Cu-containing materials in the hospital setting to minimize patient bacterial infections. Studies directed at disrupting bacterial Cu regulatory pathways elucidate new drug targets that can enable toxic increase of Cu levels and perturb bacterial dependence on iron. Likewise, Cu intracellular chelation/prochelation strategies effectively induce bacterial Cu toxicity. Cu-based small molecules and nanoparticles demonstrate the importance of the Cu ions in their mechanism and display potential synergism with classical drugs.

Carbon-based quantum dots (CBQDs), sulfur-doped carbon-based quantum dots (S-CBQDs), and nitrogen-doped carbon-based quantum dots (N-CBQDs) have strong potential for drug delivery platforms. They were conjugated with andrographolide, a well-known hydrophobic drug, to study the concomitant changes in hydrophilicity. The interactions between these nanomaterials and the drug were studied by characterizing the optical and structural properties of the nanoparticles before and after coupling with the drug. It was found that the interaction of the drug with these nanomaterials produced noticeable changes in their optical and structural properties. Moreover, the partition coefficient for the nanocomposites was determined by NMR. The results indicate that conjugating the drug with the nanoparticles significantly enhanced its affinity for the aqueous phase, from 2.632 to 0.1117, thereby opening the possibility of using this approach for developing an effective drug delivery platform for this hydrophobic drug.

The Caribbean region is a hotspot of biodiversity (i.e., algae, sponges, corals, mollusks, microorganisms, cyanobacteria, and dinoflagellates) that produces secondary metabolites such as polyketides and polypropionates. Polyketides are a diverse class of natural products synthesized by organisms through a biosynthetic pathway catalyzed by polyketide synthase (PKS). This group of compounds is subdivided into fatty acids, aromatics, and polypropionates such as macrolides, and linear and cyclic polyethers. Researchers have studied the Caribbean region to find natural products and focused on isolation, purification, structural characterization, synthesis, and conducting biological assays against parasites, cancer, fungi, and bacteria. These studies have been summarized in this review, including research from 1981 to 2020. This review includes about 90 compounds isolated in the Caribbean that meet the structural properties of polyketides. Out of 90 compounds presented, 73 have the absolute stereochemical configuration, and 82 have shown biological activity. We expect to motivate the researchers to continue exploring the Caribbean region’s marine environments to discover and investigate new polyketide and polypropionate natural products.

Classical antibacterial drugs were designed to target specific bacterial properties distinct from host human cells to maximize potency and selectivity. These designs were quite effective as they could be easily derivatized to bear next generation drugs. However, the rapid mutation of bacteria and their associated acquired drug resistance have led to the rise of highly pathogenic superbug bacterial strains for which treatment with first line drugs is no match. More than ever, there is a dire need for antibacterial drug design that goes beyond conventional standards. Taking inspiration by the body’s innate immune response to employ its own supply of labile copper ions in a toxic attack against pathogenic bacteria, which have a very low Cu tolerance, this review article examines the feasibility of Cu-centric strategies for antibacterial preventative and therapeutic applications. Promising results are shown for the use of Cu-containing materials in the hospital setting to minimize patient bacterial infections. Studies directed at disrupting bacterial Cu regulatory pathways elucidate new drug targets that can enable toxic increase of Cu levels and perturb bacterial dependence on iron. Likewise, Cu intracellular chelation/prochelation strategies effectively induce bacterial Cu toxicity. Cu-based small molecules and nanoparticles demonstrate the importance of the Cu ions in their mechanism and display potential synergism with classical drugs.

Hydrophobicity has limited the efficiency of many drugs. To improve this, gold–silver alloy nanocomposites covered with carbon-based quantum dots were synthesized as a platform to reduce the drugs’ hydrophobicity. Using the hydrophobic drug Andrographolide as a model, it was demonstrated that these nanocomposites can decrease Andrographolide’s hydrophobicity (Log P from 2.632 to 0.56) without encapsulating the drug. Entry within prostate cancer (PC-3) cells and in vitro localization of the nanocomposites and Andrographolide was observed qualitatively via confocal microscopy and their identity confirmed by SERS inside the PC-3 cells. MTS assays demonstrated the carbon-based quantum dot layer covering the metal core of the nanocomposites stabilizes the oxidation rate of the nanocomposite’s core metals. This was observed by a decrease in cytotoxicity in PC-3 cells when compared to other gold or silver nanosystems for similar timeframes published in the literature.

Carbon-based quantum dots and their nitrogen- and sulfur-doped derivatives were used as platforms to improve the aqueous solubility for Paclitaxel, Violacein and Tetrandrine, drugs with known high partition coefficients (Log P). Paclitaxel, Violacein and Tetrandrine showed a significant reduction in their partition coefficient values by coupling with the carbon-based quantum dots. Paclitaxel’s partition coefficient value decreased from 3.96 to 0.2, Violacein’s from 3.34 to 1.17, and Tetrandrine’s from 2.5 to 1.57, thus demonstrating a significant reduction in their hydrophobicity without being encapsulated. The efficiency of each type of carbon-based quantum dot in lowering each drug’s Log P varied and this behavior was correlated with the nature of the surface interaction between each drug and each of the carbon-based quantum dots.