Avermectin loaded carboxymethyl cellulose nanoparticles with stimuli-responsive and controlled release properties

Polyethylene glycol (PEG) was introduced into carboxymethyl cellulose (CMC) to form hydrophilic chain of PEG-CMC. Avermectin (Avm) was grafted on the long chain of PEG-CMC by use of N, N-dicyclohexylcarbodiimide (DCC) as the dehydrant and 4-dimethylaminopyridine (DMAP) as the catalyst to form the amphiphilic molecule. Then the avermectin nanoparticles was prepared with esterase-responsive sustained release successfully through self-assembly. The size of nanoparticles was less than 400 nm. Avermectin loading was 8% and the degradation rate was less than 50 % under the xenon arc lamp for 72 h. Compared with avermectin technical, it showed an obvious anti-photodegradation advantage. Compared with commercially available water-dispersible granules (WDG), the avermectin nanoparticles had a smaller contact angle on the cucumber leaf surface and there was a significant difference. The toxicity test showed that the nanoparticles have a certain insecticidal effect on the larva of Hyphantria cunea and the sensitivity increased gradually over time.