This study aims to synthesise and evaluate the acaricidal activity of nanoscale zinc oxide piperine formulation (NZPF) against Rhipicephalus microplus ticks. NZPF was prepared by using zinc oxide nanoparticles (ZnONPs) and piperine by employing encapsulation technique; characterised by UV spectroscopy, Fourier transformed infrared analysis, X-ray diffraction, dynamic light scattering, zetapotential and scanning electron microscopy. Acaricidal activity of the NZPF on R. microplus was evaluated using larval packet test (LPT) and adult immersion test (AIT). LPT against R. microplus larvae showed an LC ₅₀ at 1 mg/l for NZPF followed by 2 and 3 mg/l for ZnONPs and piperine, respectively. AIT against R. microplus showed an LC ₅₀ at concentration of 3 mg/l for NZPF followed by 6 mg/l for ZnONPs and 7 mg/l for piperine. In both LPT and AIT, LC ₅₀ values of ZnONPs and NZPF were significantly lower compared to deltamethrin. NZPF showed significant ovulation inhibitory activity with lower IC ₅₀ and IC ₉₉ values compared to ZnONPs and piperine. NZPF has been proved to be the better alternative to routine chemical acaricides for control of tick infestation of cattle in the wake of acaricidal resistance, but safety issues need to be addressed before clinical application.

中文翻译：

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纳米级 ZnO 包封胡椒碱制剂对 Rhipicephalus microplus 的杀螨活性评估

本研究旨在合成和评价纳米氧化锌胡椒碱制剂（NZPF）的杀螨活性。小红头鱼蜱。NZPF由氧化锌纳米颗粒（ZnONPs）和胡椒碱采用包封技术制备；通过紫外光谱、傅里叶变换红外分析、X射线衍射、动态光散射、zeta电位和扫描电子显微镜进行表征。NZPF 的杀螨活动R. microplus使用幼虫包测试（LPT）和成虫浸泡测试（AIT）进行评估。LPT 反对R. microplus幼虫对 NZPF 的 LC ₅₀为 1 mg/l，随后对 ZnONPs 和胡椒碱分别为 2 和 3 mg/l。AIT反对R. microplus显示 NZPF 的 LC ₅₀浓度为 3 mg/l，随后 ZnONP 为 6 mg/l，胡椒碱为 7 mg/l。在 LPT 和 AIT 中，ZnONPs 和 NZPF 的 LC ₅₀值显着低于溴氰菊酯。与 ZnONPs 和胡椒碱相比，NZPF 显示出显着的排卵抑制活性，IC ₅₀和 IC _{99值较低。}NZPF已被证明是常规化学杀螨剂的更好替代品，用于控制抗杀螨剂后牛的蜱虫感染，但在临床应用之前需要解决安全问题。