title: In vivo observation of gold nanoparticles in the central nervous system of Blaberus discoidalis.
abstract: BACKGROUND
  Nanoparticles (NPs) are widely studied for biomedical applications. Understanding interactions between NPs and biomolecules or cells has yet to be achieved. Here we present a novel in vivo method to study interactions between NPs and the nervous system of the discoid or false dead-head roach, Blaberus discoidalis. The aims of this study were to present a new and effective method to observe NPs in vivo that opens the door to new methods of study to observe the interactions between NPs and biological systems and to present an inexpensive and easy-to-handle biological system.
  
  
  RESULTS
  Negatively charged gold nanoparticles (nAuNPs) of 50 nm in diameter were injected into the central nervous system (CNS) of the insect. By using such a cost effective method, we were able to characterize nAuNPs and to analyze their interactions with a biological system. It showed that the charged particles affected the insect's locomotion. The nAuNPs affected the insect's behavior but had no major impacts on the life expectancy of the cockroach after two months of observation. This was apparently due to the encapsulation of nAuNPs inside the insect's brain. Based on cockroach's daily activity, we believed that the encapsulation occurred in the first 17 days.
  
  
  CONCLUSIONS
  The method proposed here is an inexpensive and reliable way of observing the response of biological systems to nanoparticles in-vivo. It opens new windows to further understand how nanoparticles affect neural communication by monitoring insect activity and locomotion.
authors.affiliation: Department of Mechanical Engineering, Texas A&M University, College Station, Texas, USA.
authors.forename: Aracely
authors.initials: A
authors.lastname: Rocha
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhou
authors.forename: Subrata
authors.initials: S
authors.lastname: Kundu
authors.forename: Jorge M
authors.initials: JM
authors.lastname: González
authors.forename: S
authors.initials: S
authors.lastname: BradleighVinson
authors.forename: Hong
authors.initials: H
authors.lastname: Liang
mesh_terms: D000818:Animals; D002490:Central Nervous System / Q000187:drug effects* / Q000648:ultrastructure; D003058:Cockroaches; D006046:Gold / Q000008:administration & dosage* / Q000191:economics; D008124:Locomotion / Q000187:drug effects; D008297:Male; D053768:Metal Nanoparticles / Q000008:administration & dosage* / Q000191:economics / Q000648:ultrastructure
chemical_list: D006046:Gold