Lucas George Santos Andrade

Background/Objectives:A. aegypti larval control is essential for reducing arbovirus transmission; however, increasing insecticide resistance and environmental concerns demand sustainable alternatives. This study reports the development of a solvent-free, thermoresponsive Pluronic F127/Carbopol 974P nanogel (NGLp) encapsulating Lippia pedunculosa Hayek essential oil (OELp) to enhance larvicidal performance through improved dispersion and controlled release (Figure ). Methods: OELp was obtained by hydrodistillation and chemically characterized by GC–MS and NMR. Nanogels were prepared using a low-energy cold method (F127 20% w/w; Carbopol 0.2% w/w), selecting the most stable formulation (1% w/w OELp). The system was characterized by FTIR, dynamic light scattering (DLS), zeta potential, and scanning electron microscopy (SEM). Larvicidal activity was evaluated against third-instar A. aegypti larvae (20–60 μg mL−1; 24, 48, and 72 h), and LC50/LC90 values were estimated by logistic fitting. Results: OELp contained 28 identified constituents (96.65%), predominantly rotundifolone (62.68%) and limonene (20.74%), with NMR confirming rotundifolone as the major compound. The optimized nanogel exhibited nanometric size (239.9 nm; PdI 0.474) and a negative zeta potential (−22.3±3.90 mV), indicating electrosterically stabilized dispersion. FTIR confirmed physical incorporation of OELp. The nanogel demonstrated dose- and time-dependent larvicidal activity, achieving 100% mortality at ≥50 μg mL−1 (48–72 h). Mortality at intermediate concentrations increased over time (e.g., 53% at 30 μg mL−1 at 72 h), indicating sustained release. LC50/LC90 values decreased from 38.6/46.0 μg mL−1 (24 h) to 31.6/40.9 μg mL−1 (48 h), with further improvement at 72 h. Conclusions: NGLp enhances larvicidal performance through improved dispersion and sustained release of OELp, supporting its potential as a sustainable and eco-compatible nanoplatform for mosquito control.

Cutaneous leishmaniasis caused by Leishmania amazonensis is a significant public health issue. This study aimed to evaluate an ecofriendly, thermosensitive nanogel, developed using a low-energy, solvent-free method, incorporating F127 and Carbopol 974P copolymers, and enriched with Pectis brevipedunculata essential oil (EOPb) for its leishmanicidal and anti-inflammatory properties. The nanogel was prepared and characterized through FTIR, DLS, SEM, and AFM to confirm the incorporation of EOPb as well as its stability and rheological properties. In vitro leishmanicidal activity was evaluated on Leishmania amazonensis promastigotes, and in vivo anti-inflammatory effects were assessed using a rat paw edema model. In vitro, nGF3 (EOPb-loaded nanogel) demonstrated significant leishmanicidal activity, with promastigote mortality rates exceeding 80% at 24 h and 90% at 48 h. In vivo, nGF1, nGF2, and nGF3 exhibited anti-inflammatory effects, with nGF2 and nGF3 reducing edema by 62.7% at 2 h post-treatment. The empty nanogel (nGF0) showed minimal anti-inflammatory activity. The ecofriendly EOPb-loaded nanogel (nGF3) demonstrated strong leishmanicidal and anti-inflammatory effects, presenting a promising candidate for cutaneous leishmaniasis treatment. Further studies are necessary to explore its clinical potential.

Background/Objectives: Cutaneous leishmaniasis caused by Leishmania amazonensis is a significant public health issue. This study aimed to evaluate an eco-friendly, thermosensitive nanogel, developed using a low-energy, solvent-free method, incorporating F127 and Carbopol 974P copolymers, and enriched with Pectis brevipedunculata essential oil (EOPb) for its leishmanicidal and anti-inflammatory properties. Methods: The nanogel was prepared and characterized through FTIR, DLS, SEM, and AFM to confirm the incorporation of EOPb, stability and rheological properties. In vitro leishmanicidal activity was evaluated on Leishmania amazonensis promastigotes, and in vivo anti-inflammatory effects were assessed using a rat paw edema model. Results: In vitro, nGF3 (EOPb-loaded nanogel) demonstrated significant leishmanicidal activity, with promastigote mortality rates exceeding 80% at 24 h and 90% at 48 h. In vivo, nGF1, nGF2, and nGF3 exhibited anti-inflammatory effects, with nGF2 and nGF3 reducing edema by 62.7% at 2 h post-treatment. The empty nanogel (nGF0) showed minimal anti-inflammatory activity. Conclusions: The eco-friendly EOPb-loaded nanogel (nGF3) demonstrated strong leishmanicidal and anti-inflammatory effects, presenting a promising candidate for cutaneous leishmaniasis treatment. Further studies are necessary to explore its clinical potential.