Abstract

The objective of this study is to synthesize neem-silver nitrate nanoparticles (neem-AgNPs) using aqueous extracts of Azadirachta indica A. Juss for malaria therapy. Neem leaves collected from FRIM Malaysia were authenticated and extracted using Soxhlet extraction method. The extract was introduced to 1 mM of silver nitrate solution for neem-AgNPs synthesis. Synthesized AgNPs were further characterized by ultraviolet-visible spectroscopy and the electron-scanning microscopy. Meanwhile, for the anti-plasmodial activity of the neem-AgNPs, two lab-adapted Plasmodium falciparum strains, 3D7 (chloroquine-sensitive), and W2 (chloroquine-resistant) were tested. Red blood cells hemolysis was monitored to observe the effects of neem-AgNPs on normal and parasitized red blood cells. The synthesized neem-AgNPs were spherical in shape and showed a diameter range from 31−43 nm. When compared to aqueous neem leaves extract, the half inhibitory concentration (IC₅₀) of the synthesized neem-AgNPs showed a four-fold IC₅₀ decrease against both parasite strains with IC₅₀ value of 40.920 µg/mL to 8.815 µg/mL for 3D7, and IC₅₀ value of 98.770 µg/mL to 23.110 µg/mL on W2 strain. The hemolysis assay indicates that the synthesized neem-AgNPs and aqueous extract alone do not have hemolysis activity against normal and parasitized red blood cells. Therefore, this study shows the synthesized neem-AgNPs has a great potential to be used for malaria therapy.

摘要

本研究的目的是利用印楝A. Juss 的水提取物合成印楝-硝酸银纳米颗粒 (neem-AgNPs) 用于疟疾治疗。从马来西亚 FRIM 采集的印楝叶使用索氏提取法进行鉴定和提取。将提取物引入 1 mM 硝酸银溶液中用于印楝-AgNPs 合成。通过紫外-可见光谱和电子扫描显微镜对合成的 AgNPs 进行了进一步的表征。同时，对于 neem-AgNPs 的抗疟原虫活性，两种实验室适应的恶性疟原虫测试了 3D7（氯喹敏感）和 W2（氯喹抗性）菌株。监测红细胞溶血以观察印楝-AgNPs对正常和寄生红细胞的影响。合成的 neem-AgNPs 呈球形，直径范围为 31-43 nm。与水楝叶提取物相比，合成的 neem-AgNPs的半抑制浓度 (IC ₅₀ )对两种寄生虫菌株的IC _{50降低了四倍，IC 50}值为 40.920 µg/mL 至 8.815 µg/mL，3D7 , 和 IC ₅₀W2 菌株的值为 98.770 µg/mL 至 23.110 µg/mL。溶血测定表明，合成的印楝-AgNPs 和单独的水提取物对正常和寄生的红细胞没有溶血活性。因此，本研究表明合成的印楝-AgNPs 具有用于疟疾治疗的巨大潜力。