Malaria, the most widespread mosquito-borne disease, affects 350-500 million people each year. Eco-friendly control tools against malaria vectors are urgently needed. This research proposed a novel method of plant-mediated synthesis of silver nanoparticles (AgNP) using a cheap seaweed extract of Ulva lactuca, acting as a reducing and capping agent. AgNP were characterized by UV-vis spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The U. lactuca extract and the green-synthesized AgNP were tested against larvae and pupae of the malaria vector Anopheles stephensi. In mosquitocidal assays, LC50 values of U. lactuca extract against A. stephensi larvae and pupae were 18.365 ppm (I instar), 23.948 ppm (II), 29.701 ppm (III), 37.517 ppm (IV), and 43.012 ppm (pupae). LC50 values of AgNP against A. stephensi were 2.111 ppm (I), 3.090 ppm (II), 4.629 ppm (III), 5.261 ppm (IV), and 6.860 ppm (pupae). Smoke toxicity experiments conducted against mosquito adults showed that U. lactuca coils evoked mortality rates comparable to the permethrin-based positive control (66, 51, and 41%, respectively). Furthermore, the antiplasmodial activity of U. lactuca extract and U. lactuca-synthesized AgNP was evaluated against CQ-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of Plasmodium falciparum. Fifty percent inhibitory concentration (IC50) values of U. lactuca were 57.26 μg/ml (CQ-s) and 66.36 μg/ml (CQ-r); U. lactuca-synthesized AgNP IC50 values were 76.33 μg/ml (CQ-s) and 79.13 μg/ml (CQ-r). Overall, our results highlighted out that U. lactuca-synthesized AgNP may be employed to develop newer and safer agents for malaria control.

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A main challenge in parasitology is the development of reliable tools to prevent or treat mosquito-borne diseases. We investigated the toxicity of magnetic nanoparticles (MNP) produced by Magnetospirillum gryphiswaldense (strain MSR-1) on chloroquine-resistant (CQ-r) and sensitive (CQ-s) Plasmodium falciparum, dengue virus (DEN-2), and two of their main vectors, Anopheles stephensi and Aedes aegypti, respectively. MNP were studied by Fourier-transform infrared spectroscopy and transmission electron microscopy. They were toxic to larvae and pupae of An. stephensi, LC ranged from 2.563 ppm (1st instar larva) to 6.430 ppm (pupa), and Ae. aegypti, LC ranged from 3.231 ppm (1st instar larva) to 7.545 ppm (pupa). MNP IC on P. falciparum were 83.32 μg ml (CQ-s) and 87.47 μg ml (CQ-r). However, the in vivo efficacy of MNP on Plasmodium berghei was low if compared to CQ-based treatments. Moderate cytotoxicity was detected on Vero cells post-treatment with MNP doses lower than 4 μg ml. MNP evaluated at 2-8 μg ml inhibited DEN-2 replication inhibiting the expression of the envelope (E) protein. In conclusion, our findings represent the first report about the use of MNP in medical and veterinary entomology, proposing them as suitable materials to develop reliable tools to combat mosquito-borne diseases.

Recently, it has been highlighted an overlooked connection between the biting activity of Anopheles mosquitoes and the spread of cancer. The excellent physico-chemical properties of graphene quantum dots (GQDs) make them a suitable candidate for biomedical applications. We focused on the toxicity of GQDs

The development of pathogens and parasites resistant to synthetic drugs has created the need for developing alternative approaches to fight vector-borne diseases. In this research, we fabricated green-synthesized silver nanoparticles (AgNP) using Musa paradisiaca stem extract as a reducing and stabilizing agent. AgNP showed plasmon resonance reduction under UV-Vis spectrophotometry, SEM and XRD highlighted that they were crystalline in nature with face centered cubic geometry. . AgNP showed growth inhibition activity against bacteria and fungi of public health relevance. AgNP were a valuable candidate for treatment of diabetes in STZ-treated rat by normalizing glucose, galactose and insulin. AgNP were toxic against larvae and pupae of the malaria vector Anopheles stephensi, with LC 50 of 3.642 (I), 5.497 (II), 8.561 (III), 13.477 (IV), and 17.898 ppm (pupae), respectively. Furthermore, the antiplasmodial activity of nanoparticles was evaluated against CQ-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of Plasmodium falciparum, IC 50 were 84.22 lg/ml (CQ-s) and 89.24 lg/ml (CQ-r), while chloroquine IC 50 were 86 lg/ml (CQ-s) and 91 lg/ml (CQ-r). Overall, we add knowledge on the multipurpose effectiveness of green-fabricated nanoparticles in medicine and parasitology, which can be potentially helpful to develop newer and safer antiplasmodial agents and vector control tools.

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Anopheles stephensi is a mosquito of outstanding public health relevance, acting as a major vector of malaria in a number of tropical and subtropical areas worldwide. In recent years, important efforts have been conducted to propose nano-formulated larvicides as valuable alternatives to synthetic insecticides currently marketed. In the present study, the toxicity of flower-like copper sulfide (CuS) nanocrystals has been investigated on the malaria vector A. stephensi and Plasmodium parasites. Characterization of synthesized CuS nanocrystals was carried out using FTIR spectroscopy, XRD analysis, FESEM, HR-TEM and EDS. In mosquitocidal assays, LC 50 values ranged from 23.347 ppm (first-instar larvae) to 48.789 ppm (pupae). In vitro anti-plasmodial activity of CuS nanoflowers was evaluated against chloroquine-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of Plasmodium falciparum. IC 50 were 83.44 μg/mL (CQ-s) and 87.15 μg/mL (CQ-r). However, in vivo antiplasmodial experiments conducted on Plasmodium berghei infecting albino mice showed limited activity of CuS nanocrystals, if compared to CQ. Overall, our findings showed that chemically synthesized flower-like CuS nanocrystals are promising to improve the effectiveness of mosquito control programs, as well as to develop novel antiplasmodial drugs.