A series of Ru(II)-PC(n)P-Au(I) (n = 1-5) bimetallic complexes were successfully synthesized and characterized with phosphorus (31P{H}) and proton (1H) nuclear magnetic resonance (NMR) spectroscopy, electrospray ionization mass spectrometry (ESI-MS), supported by crystallographic data. Correlations between resonance shifts and P-Au(I) bond distances provided insight into the electronic environment of the phosphorus centers, while single-crystal X-ray diffraction confirmed the molecular structures. Hirshfeld surface analysis revealed dominant H···H and F···H/H···F interactions, with contact percentages varying systematically with carbon chain length. Biological evaluation showed that the complexes exhibited higher cytotoxicity than cisplatin and melphalan against HeLa and Caco2 cancer cell lines, with pincer ligand carbon chain-length-dependent activity: shorter chains were more potent in HeLa cells, whereas longer chains were more effective in Caco2 cells. Most complexes displayed cytostatic activity, with compound 2b demonstrating the best overall performance, combining strong cytostatic properties with high selectivity toward cancerous cells. These findings highlight the structural, electronic, and biological relationships of the complexes, underlining their potential as anticancer agents.

Tetracycline (TC) contamination of aquatic systems poses severe ecological and public health challenges. This study compares four bio-derived carbon adsorbents utilizing targeted iron-functionalization strategies to optimize antibiotic decontamination: (A) thermally modified Acacia mearnsii bark extract, (B) A. mearnsii carbon loaded with 25% Fe(OH)3 (acidic precipitation), (C) A. mearnsii carbon loaded with 25% Fe(OH)3 (NH4OH-adjusted), and (D) a delignified cellulose-derived carbon-fibre composite bearing surface iron oxide/oxyhydroxide phases. Nitrogen physisorption revealed a transition from mesoporous architectures (Type IV(a), Sample A) to highly microporous frameworks (Type I(a), Sample D), with t-plot micropore volumes increasing from 0.032 to 0.102 cm3 g-1. High-resolution Fe 2p XPS confirmed that the surface iron species are predominantly Fe(iii) (hydr)oxides. Non-linear kinetic modelling of the 20-120 min uptake data showed that the pseudo-first-order model provided the best statistical description for all samples (R 2 = 0.950-0.995). The fitted equilibrium capacities ranged from 6.57 to 9.48 mg g-1, remaining within the 10 mg g-1 mass-balance limit imposed by the kinetic conditions (C 0 = 10 mg L-1; dosage = 1.0 g L-1). Intraparticle-diffusion analysis indicated that diffusion contributed to TC uptake but was not the sole rate-controlling process. Under optimized batch parameters (1.0 g L-1, C 0 = 10 mg L-1, 25 °C), maximum TC removal efficiencies were 92.7% at pH 7.0 (A), 88.7% at pH 5.0 (B), 84.6% at pH 5.0 (C), and 90.0% at pH 7.0 (D). Equilibrium data were best described by the Freundlich model for Sample A (R 2 = 0.997) and by the Langmuir model for Samples B-D. The fitted Langmuir capacities of 20.3-20.8 mg g-1 were obtained from the isotherm dataset collected at initial TC concentrations of 10-40 mg L-1 and should not be interpreted as capacities measured under the separate fixed-concentration kinetic condition of C 0 = 10 mg L-1. Sample D achieved 77.5 ± 0.5% TC removal efficiency in the fourth regeneration cycle, corresponding to 86.5% relative retention of its first-cycle removal efficiency. This four-cycle result provides preliminary laboratory-scale evidence of reusability under the tested conditions.

BACKGROUND:Endocrine-disrupting chemicals (EDCs) such as phthalates, bisphenols, and parabens are widely used in consumer products and have been associated with reproductive toxicity, hormonal imbalance, and cancer. Menstrual products represent a potential but under-recognized source of exposure. In South Africa, several brands advertise as being free from harmful chemicals, yet limited research has verified these as potential EDC sources. OBJECTIVE:This study aimed to evaluate the occurrence and profiles of phthalates, parabens, and bisphenols in sanitary pads and panty liners sold in South Africa. To estimate dermal exposure to these EDCs through menstrual product use and determine the significance of sanitary pads as a potential source of EDC exposure. METHODS:A total of 20 EDCs, including nine phthalates, five parabens, and six bisphenols, were analysed in 16 commercially available sanitary pads and seven panty liners in South Africa. The selected compounds were detected and quantified using chromatographic analysis and estimated daily exposure doses were subsequently calculated to evaluate potential health risks. RESULTS:EDCs were detected and quantified in all tested samples, with each pad and liner containing at least two of the target EDCs. The detection frequencies (DFs) of phthalates, bisphenols, and parabens in liners were 100%, 75%, and 75%, respectively, and 50%, 100%, and 85% in pads. Phthalates were more prevalent in liners, compared to bisphenols in pads. CONCLUSION:This study revealed the presence of EDCs in sanitary pads and liners in South Africa, identifying menstrual products as a significant but overlooked source of toxic exposure. Although daily doses may seem low, the long-term, repeated contact with sensitive tissues poses cumulative health risks, including reproductive toxicity and cancer. SIGNIFICANCE:This study provides the first comprehensive data on EDC contamination in sanitary pads and panty liners sold in South Africa, addressing a gap in regional exposure research.

Melamine foam (MF) was chemically modified with various benzaldehyde (BA) derivatives via Schiff-base formation to enhance its hydrophobicity and oleophilicity for oil spill remediation. BA derivatives with nitro, chloro, methyl, or carboxy groups were grafted onto MF through acid-catalyzed condensation with surface amines, forming imine-linked (C=N) structures. SEM showed the foam's porous 3D network remained intact, while FTIR confirmed Schiff-base formation. Water contact angle measurements indicated significantly increased hydrophobicity in all modified foams except the carboxy-substituted variant (CBA-MF), which remained more hydrophilic due to hydrogen bonding. Hydrophobicity trends correlated inversely with substituent electronegativity. Modified MFs showed strong oil selectivity, efficiently absorbing nonpolar oils while repelling water—especially nitrobenzaldehyde-modified MF (NBA-MF), which floated and absorbed oil effectively. Adsorption tests showed high capacities (up to 149 g/g), correlating with surface hydrophobicity. Modified foams were durable, retaining over 90 % adsorption capacity after 10 reuse cycles. Paraffin oil adsorption followed zero-order kinetics, with rates increasing alongside hydrophobicity. Overall, Schiff-base modification successfully transformed MF into a reusable, highly effective sorbent for selective oil recovery in water.

Wastewater treatment has garnered significant attention due to the increasing prevalence of industrial processes and the associated environmental challenges. Sustainable alternatives to traditional wastewater treatment technologies are urgently required to address the escalating environmental crisis. Photocatalysis has emerged as a promising technique for wastewater treatment, particularly for the degradation of pharmaceutical compounds, organic contaminants, and microbes. Among them, the perovskite semiconductor piezoelectric barium titanate (BaTiO3) has demonstrated immense potential due to its advantageous properties, including non-toxicity, low cost, environmental friendliness, high stability, and versatility in crystal phases and morphologies. Despite its promise, BaTiO3 photocatalysts face challenges such as limited photocatalytic efficiency under visible light, scalability issues for industrial applications, and potential environmental risks associated with nanomaterial residues. Polymer doping, while effective in enhancing photocatalytic performance, introduces complexities in synthesis and increases production costs. Addressing these challenges requires optimizing the synthesis of BaTiO3 to balance cost, efficiency, and environmental compatibility. Additionally, critically assessing its lifecycle impacts and exploring synergistic effects with other advanced treatment methods are imperative for ensuring its practical and sustainable application in water pollution mitigation. This review highlights the role of BaTiO3 photocatalysts in degrading active pharmaceutical ingredients (APIs) and their application in aquatic environments, both with and without polymer doping. It also discusses the health risks of APIs in water and suggests future research directions. The findings aim to aid in developing cost-effective, efficient photocatalysts for wastewater treatment to promote sustainable water management.

With the global agricultural sector facing major challenges including; drought, water runoff, and fertiliser loss, the growing demand for sustainable practices has intensified. As a result, superabsorbent polymers (SAPs) have garnered attention due to their ability to improve soil water retention and the controlled, slow-release of nutrient molecules. This study explores the synthesis and characterisation of semi-synthetic chitin-based SAPs derived from shellfish waste, offering an eco-friendly alternative to conventional synthetic SAPs. Two SAP variants were synthesised: one without urea (SCNU) and the other incorporating urea (SCU) to enhance solubility and performance. The chemical structure, absorption kinetics, and urea slow-release behaviour were analysed using Fourier-transform infrared (FTIR) spectroscopy, zeta potential measurements, and UV/Vis spectrophotometry. Results revealed that the urea-based SAP (SCU) exhibited superior water absorption and swelling capacity, reaching a maximum absorption capacity of 355 g/g compared to 155 g/g for SCNU SAP. Both SAPs exhibited good biodegradability within just 7 days, highlighting their environmental benefit. We also investigated the SAPs' surface charge behaviour across a range of pH values by measuring zeta potential, which provided insight into their water absorption capacity in varying environmental conditions. Absorption experiments supported the trends observed in the zeta potential analysis. As pH increases, the surface charge becomes more negative, which enhances electrostatic repulsion between polymer chains and results in greater water absorption. Desorption studies showed sustained water release over 14 days, indicating potential to reduce irrigation frequency. Post-synthetic urea loading confirmed the SAPs' slow-release fertiliser capability. Incorporation of indole butyric acid (IBA) further enhanced plant growth, demonstrating the SAPs' dual function in moisture retention and nutrient delivery.

The transition to a sustainable chemical industry necessitates the development of environmentally friendly solvents and catalysts. Carbon dioxide utilization reactions offer a promising avenue for reducing greenhouse gas emissions, but their commercialization depends on the availability of green catalysts and solvents. Traditional options often suffer from toxicity, volatility, and flammability, hindering their industrial application. Natural deep eutectic solvents (NADES) present a sustainable alternative. This study explores the potential of NADES derived from choline chloride (ChCl) and indole-3-butyric acid (IBA) as catalysts for the cycloaddition of CO2 with epichlorohydrin. Nine NADES compositions were prepared and characterized using FTIR, NMR, DSC, and TGA. The [ChCl] : [IBA] (0.8 : 0.2) mixture exhibited the lowest melting point (4.4 degrees C) and the highest catalytic activity (TOF = 1091 h 1). Under optimized conditions, the catalyst demonstrated excellent reusability, maintaining its activity over four catalytic cycles.

We report the synthesis and characterization of two series of dinuclear gold(I) complexes with different N-substituted (R) bridging bis(diphenylphosphino)amine (PNP) ligands (R = n-butyl, cyclobutyl, cyclopentyl, cyclohexyl, 2-butyl, 1,2-dimethylpropyl): paired with either nitrate or hexafluoroantimonate counterions. Single-crystal X-ray diffraction studies on four hexafluoroantimonate salts revealed Au⋯Au distances ranging from 2.754 Å to 2.830 Å. These crystal structures provide the first crystallographic evidence of an aliphatic N-substituent in complexes of this nature. Despite these structural variations, solid-state photoluminescence studies showed no significant variation in the emission and excitation wavelengths of these complexes across the N-substituted series. In contrast, significant differences in the photophysical properties (especially the emission energies and lifetimes) were observed as a function of the counterion, highlighting the important role of anion identity in modulating photophysical properties. Time-dependent density functional theory (TD-DFT) computations at the TPSSh level reproduced the experimental trends and attributed the counterion-induced emission redshift to weak bonding interactions between the gold centers and coordinating anions, such as nitrate and chloride.

A composite of gold and carboxymethyl cellulose (Au-CMC) was prepared from gold(III) chloride and the sodium salt of carboxymethyl cellulose. The prepared composite was characterized by using X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX). Then, ferric reducing, nitric oxide scavenging and free radical scavenging activities of the synthesized Au-CMC were carried out. In addition, inhibitory activities of the material against α-amylase, α-glucosidase enzymes and SARS-CoV-2 were studied. It was found that the material displayed good antioxidant activities. Especially, its NO scavenging activities was higher than that of vanillin, gold nanoparticles and carboxymethyl cellulose alone. The α-glucosidase enzyme inhibitory effect of the material was better than that of acarbose. Findings also revealed that both CMC and Au-CMC are highly potent against B1.351 and BQ.1.1 variants of SARS-CoV-2. Finally, cytotoxicity studies showed that the two compounds can be used safely in biomedical applications, such as drug delivery, tissue engineering, or as stabilizers in formulations, without concerns.

Breast cancer continues to be the biggest cause of mortality for women worldwide, taking the lives of millions each year. As a result, scientists are now exploring the possibility of metal-based complexes as anticancer therapies. Notwithstanding, polypyridyl coordinated Re(I) complexes have demonstrated tremendous promise as cancer-fighting medications. Therefore, the intent of this research is to investigate theoretically the spectral properties, compute density functional theory (DFT), and simulate molecular docking of polypyridyl coordinated Re(I) complexes containing functionalized 2,2′-bipyridine N,N′-donor bidentate ligands: 5,5′-DiMBpy coordinated in (1a), 4,4′-DiMBpy coordinated in (2a), and 4,4′-DiMoxBp coordinated in (3a) for cancer therapy application. Intriguingly, the complex Re(2a) achieved the greatest MolDock score and H-bond energy following interactions with the target receptors utilized, followed by Re(1a) and Re(3), respectively. Thus elucidating the studied compounds to be efficient in the mitigation of breast cancer.

Sensors implemented in agriculture play a significant role in soil and plant growth and enable real-time physical and chemical interactions in the environment, such as temperature, moisture/humidity, pH, and contaminant levels. Additionally, these sensors provide essential data that can enhance crop growth scenarios, resist biotic and abiotic stresses, and improve crop production. This article provides a thorough examination of the evolving landscape of agricultural sensor technologies, perspectives, and challenges in the field. Currently, some of the key soil sensors used in agricultural programs, include those that measure moisture, temperatures, pH, organic matter components, insects, and soil pollutants. On the other hand, nanobiotechnology sensors implement optical, wireless, or electrical signals to provide information about plant signaling molecules related to the conditions of agronomic equipment. We shed more light on the use of nanomaterial-facilitated transport of genetically encoded sensors as devices for the investigation and advancement of advanced plant sensors. Innovative technologies, including wireless sensor networks and plant wearables, are also addressed with regard to their potential for precision agriculture. The paper concludes by presenting future perspectives and difficulties in the fields of soil sensors and intelligent agriculture. In summary, we provide a comprehensive and forward-looking perspective on the potential of nanotechnology to facilitate the development of intelligent plant sensors. These sensors are capable of communicating with and controlling electrical equipment, with the aim of tracking and improving the output and resources applied to individual plants.

The accumulation of greenhouse gases (GHG) in the atmosphere, with carbon dioxide being the most significant contributor, is a major environmental problem as it impacts significantly on climate change. The development of new catalysts and chemical reactions that incorporate CO2 are needed to reduce its further emission significantly. Deep eutectic solvents (DES) have garnered increasing attention as environmentally friendly catalysts in the cycloaddition of carbon dioxide (CO2) with epoxide substrates to produce cyclic carbonates. Their appeal stems from their facile synthesis, cost-effectiveness, low vapour pressure, and thermal stability. In this study, we present a convenient solvent-free synthesis method for nine deep eutectic solvents (DES), utilizing varying compositions of quaternary amine salts (N,N,N-triethyldodecan-1-aminium hydroxide, [TEA-12][OH]) and quinaldic acid [Q-COOH]. These deep eutectic solvents were thoroughly characterized using several techniques, including FTIR, NMR, DSC, and TGA. Moreover, their efficacy for the solvent-free fixation of CO2 to cyclic carbonates were evaluated. Among the tested compositions, [TEA-12]:[Q-COOH] (0.9:0.1) exhibited the lowest melting point (100.17 degrees C) and highest catalytic activity, showcasing an optimized Turn-Over Frequency (TOF) of 1466 h(-1). This remarkable result represents a significant advancement in the application of DES for CO2 fixation, exceeding the previous highest catalytic activity observed with TBAB:Citric acid (2.5:1) by more than tenfold.

The synthesis, characterisation, crystal structures and cytotoxicity against HeLa cells of three rhenium complexes fac-[Re(CO)3(PMA)]+ (PMA = bis(2-pyridylmethyl)amine), fac-[Re(CO)3(PMAEth)]+ (PMAEth = bis(2-pyridylmethyl)-2-aminoethanol), and fac-[Re(CO)3(PMAProp)]+ (PMAProp = bis(2-pyridylmethyl)-2-aminopropanol) are reported. The tripodal ligands showed slightly higher cytotoxicity than the coordinated complexes with IC50 values ranging from 10 mu M to 38 mu M. These values, together with the fact that the ligand backbones can be easily modified to introduce higher toxicity, supports the possible use of Rhenium(I) as a theranostic radiopharmaceutical.

Gamma-aminobutyric acid (GABA) signaling is the principal inhibitory pathway in the central nervous system. It is critical in neuronal cell proliferation and fate determination. Any aberration in GABA inhibition results in psychiatric and neurological diseases. Thus, modulating GABAergic neurotransmission has become the basis of drug therapy for psychiatric and several neurological diseases. Though GABA and muscimol are classical inhibitors of GABA receptors, the search for novel inhibitors continues unabated. In this study, the binding mechanism of GABA and muscimol was elucidated and applied in the search for small molecule GABAergic inhibitors using comprehensive computational techniques. It was revealed that a high-affinity binding of GABA and muscimol was mediated by a water molecule involving alpha(1)Thr129 and then stabilized by strong interactions including salt bridges with beta(2)Glu155 and alpha(1)Arg66 amidst hydrogen bonds, pi-pi stacking, and pi -cation interactions with other residues. The binding of GABA and muscimol was also characterized by stability and deeper penetration into the hydrophobic core of the protein which resulted in conformational changes of the binding pocket and domain, by inducing correlated motions of the residues. Thermodynamics analysis showed GABA and muscimol exhibited total binding free energies of -19.85 +/- 8.83 Kcal/mol and -26.55 +/- 3.42 Kcal/mol, respectively. A pharmacophore model search, based on the energy contributions of implicating binding residues, resulted in the identification of ZINC68604167, ZINC19735138, ZINC04202466, ZINC00901626, and ZINC01532854 as potential GABA-mimetic compounds from metabolites and natural products libraries. This study has elucidated the binding mechanisms of GABA and muscimol and successfully applied in the identification of GABA-mimetic compounds.

To gain insights into the activity of metal-based drugs against SARS-CoV-2, five rhenium complexes, namely fac-[Re(CO)(3)(acac)(PPh2Cy)] (I), fac-[Re(CO)(3)(acac)(PPhCy2)] (II), fac-[Re(CO)(3)(acac)(PCy3)] (III), fac-[Re(CO)(3)(acac)(P(m-tolyl)(3))] (IV), and fac-[Re(CO)(3)(acac)(P(p-tolyl)(3))] (V), with acac=acetylacetonato, PPh2Cy=cyclohexyldiphenylphosphine, PPhCy2=dicyclohexylphenylphosphine, PCy3=tricyclohexylphosphine, P(m-tolyl)(3)=tri(m-tolyl)phosphine, and P(p-tolyl)(3)=tri(p-tolyl)phosphine, were docked in the binding pockets of main protease, spike glycoprotein, and RNA-dependent RNA polymerase. The resulting binding sites revealed potent SARS-CoV-2 inhibition, resulting from the formation of classical N-H & sdot;& sdot;& sdot;O and O-H & sdot;& sdot;& sdot;O hydrogen bonds, carbon C-H & sdot;& sdot;& sdot;O H-bonds, hydrophobic contacts, as well as non-conventional interactions such as weak C-H & sdot;& sdot;& sdot;N interactions, H & sdot;& sdot;& sdot;H, C & sdot;& sdot;& sdot;H/H & sdot;& sdot;& sdot;C, C & sdot;& sdot;& sdot;lp/lp & sdot;& sdot;& sdot;C and lp & sdot;& sdot;& sdot;lp contacts, cation-pi interactions and pi & sdot;& sdot;& sdot;pi stacking in the targets' binding pockets. Moreover, we have optimized the molecular structures of these compounds using DFT methods and correlated them correspondingly to their crystal structures. We have estimated and evaluated the associated frontier molecular orbitals, as well as the global reactivity descriptors for which we have discussed the compounds' reactivity. We have also examined intermolecular interactions by carrying out a Hirshfeld surface (HS) analysis, which showed the presence of C-H & sdot;& sdot;& sdot;H-C, C-H & sdot;& sdot;& sdot;C interactions, C-H & sdot;& sdot;& sdot;O non-classical hydrogen bonds and pi & sdot;& sdot;& sdot;pi stacking, as well as non-conventional pi & sdot;& sdot;& sdot;lp and lp & sdot;& sdot;& sdot;lp interactions.

In low- to middle-income communities, the lack of affordability of conventional sanitary products during menstrual cycles can cause psychological and health issues, ultimately affecting their quality of life. It is crucial to develop alternative products that are affordable and accessible to all while also promoting menstrual health and hygiene. Super absorbent polymers (SAPs) are a vital component in current disposable sanitary pads and nappies. However, these SAPs are often non-biodegradable and non-biocompatible. Therefore, the use of eco-friendly materials for the production of SAPs is gaining popularity in the hygiene industry, as it offers a means to reduce the carbon footprint and environmental impact associated with traditional SAPs made from non-renewable petroleum-based materials. SAPs made from polysaccharides often have naturally occurring antibacterial properties, making them appealing for commercial applications in sanitary products such as sanitary pads. In addition, the move toward reusable sanitary pads with antibacterial properties can significantly reduce waste generated by single-use products and prevent the growth of bacteria, improving the safety and hygiene of the product. Furthermore, computational modeling and artificial intelligence are now important tools in SAP synthesis, providing advantages such as predicting polymer properties, rationalizing synthesis pathways, and improving quality control. These tools can reduce synthesis costs by eliminating the need for trial-and-error approaches in polymer synthesis, ultimately promoting more affordable products for end users. Overall, these advancements in polymer synthesis and material design can help to create a more sustainable industry and promote menstrual hygiene and product accessibility to those who need it most.

Integrating nanoparticles (NPs) with fabric holds great potential for enhancing material properties and expanding the applications of textiles. Some advantages induced in this manner include improved durability, enhanced colour fastness, antibacterial properties, reduced environmental impact, thermal stability, tensile strength, water repellence, UV protection, and abrasion resistance. This review explores current research and developments in fabric engineering using NPs and mainly chemical methods, with a special focus on general health management. It also discusses the challenges and opportunities related to large-scale production and commercialization of fixed NPs in fabric manufacturing. Additionally, various fixation methods are examined, along with the potential difficulties that may arise during implementation. Special focus is given to using chitosan in these types of materials. Whilst increased research in this area is a strong indication of interest, issues like particle instability, agglomeration, leaching, poor adhesion, potential toxicity, and the impact on mechanical properties are still complications in many processes.

C15H12Br0.2Cl0.8N2O3Re1, monoclinic, P21/c (no. 14), a = 14.6713(4) Å, b = 11.4724(3) Å, c = 9.6206(3) Å, β = 106.592 (3), V = 1551.87(8) Å3, Z = 4, Rgt(F) = 0.0452, wRref(F2) = 0.1110, T = 149.99(10) K.

Eight rhenium(I) tricarbonyl aqua complexes with the general formula fac-[Re(CO)3(N,N'-bid)(H2O)][NO3] (1-8), where N,N'-bid is (2,6-dimethoxypyridyl)imidazo[4,5-f]1,10-phenanthroline (L1), (indole)imidazo[4,5-f]1,10-phenanthroline (L2), (5-methoxyindole)-imidazo[4,5-f]1,10-phenanthroline (L3), (biphenyl)imidazo[4,5-f]1,10-phenanthroline (L4), (fluorene)imidazo[4,5-f]1,10-phenanthroline (L5), (benzo[b]thiophene)imidazo[4,5-f]1,10-phenanthroline (L6), (5-bromothiazole)imidazo[4,5-f]1,10-phenanthroline (L7), and (4,5-dimethylthiophene)imidazo[4,5-f]1,10-phenanthroline (L8), were synthesized and characterized using 1H and 13C{1H} NMR, FT-IR, UV/Vis absorption spectroscopy, and ESI-mass spectrometry, and their purity was confirmed by elemental analysis. The stability of the complexes in aqueous buffer solution (pH 7.4) was confirmed by UV/Vis spectroscopy. The cytotoxicity of the complexes (1-8) was then evaluated on prostate cancer cells (PC3), showing a low nanomolar to low micromolar in vitro cytotoxicity. Worthy of note, three of the Re(I) tricarbonyl complexes showed very low (IC50 = 30-50 nM) cytotoxic activity against PC3 cells and up to 26-fold selectivity over normal human retinal pigment epithelial-1 (RPE-1) cells. The cytotoxicity of both complexes 3 and 6 was lowered under hypoxic conditions in PC3 cells. However, the compounds were still 10 times more active than cisplatin in these conditions. Additional biological experiments were then performed on the most selective complexes (complexes 3 and 6). Cell fractioning experiments followed by ICP-MS studies revealed that 3 and 6 accumulate mostly in the mitochondria and nucleus, respectively. Despite the respective mitochondrial and nuclear localization of 3 and 6, 3 did not trigger the apoptosis pathways for cell killing, whereas 6 can trigger apoptosis but not as a major pathway. Complex 3 induced a paraptosis pathway for cell killing while 6 did not induce any of our other tested pathways, namely, necrosis, paraptosis, and autophagy. Both complexes 3 and 6 were found to be involved in mitochondrial dysfunction and downregulated the ATP production of PC3 cells. To the best of our knowledge, this report presents some of the most cytotoxic Re(I) carbonyl complexes with exceptionally low nanomolar cytotoxic activity toward prostate cancer cells, demonstrating further the future viability of utilizing rhenium in the fight against cancer.