In this paper we describe the double nanohole laser tweezer system used to trap single nanoparticles. We cover the basic theory behind the DNH and what makes it more powerful than traditional laser tweezers commonly used for larger particles. We outline the basic setup used to reliably trap several different types of particles ranging in size from 1 nm to 40 nm. Data from several experiments is shown which displays exactly how a particle is confirmed to be trapped. We will discuss the use of autocorrelation as well as other information that can be extracted from the optical transmission in our setup and how it has been applied to the identification of protein small molecule interactions and protein binding. Other uses of the data collected from our setup will be discussed including the observation of protein folding. Finally we discuss the current developments of the process and its possible uses as a drug discovery tool, a new type of single particle nanopipette and new bio-sensors.