Nanoparticle : design , characterization and evaluation for oral delivery of ropinirole hydrochloride

Introduction Nanotechnology is the application of science and technology to control matter at the molecular level. At the nanoscale level, the properties of matter are significantly different from their macroscopic bulk properties. Nanotechnology is also referred to the ability for designing, characterization, production and application of structures, devices and systems by controlling shape and size at the nanometer scale [1]. Nanoparticles are viewed as the fundamental building blocks of nanotechnology. They are the starting points for preparing many nanostructured materials and devices. Their synthesis is an important component of the rapidly growing research efforts in nanoscience and nanoengineering. The nanoparticles of a wide range of materials can be prepared by a number of methods. In synthesis and assembly strategies of nanoparticles or nanomaterials, precursors from liquids, solid or gas phase are used. The submicron size of nanoparticles offers numerous advantages over microparticles. Nanoparticles have relatively higher intracellular uptake compared to microparticles. In the last decade, significant effort has been made to develop nanoparticles for drug delivery [2]. Poloxamers are used in a variety of oral, parenteral, and topical pharmaceutical formulations, and are generally regarded as nontoxic and nonirritant materials. Poloxamers are not metabolized in the body . So it has been the choice of polymer for the preparation of the Nanoparticles [3]. Oral absorption of ropinirole hydrochloride is rapid and essentially complete. Bioavailability of Ropinirole hydrochloride is approximately 50% (36% to 57%) and average peak concentrations of the drug are achieved at a median time of 1.5 hours post dose. The bioavailability of Ropinirole hydrochloride was similar in both the fed and fasted state. As adjunctive treatment of L-dopa, Ropinirole hydrochloride enhances the efficacy of L-dopa, including control of "on-off" fluctuations and "end of dose" effects associated with chronic Ldopa therapy and permits reduction in daily L-dopa dose [4]. High aqueous solubility and low bioavailability lead ropinirole hydrochloride to comparatively less brain access. So the investigation of the study was to develop a novel dosage form for the accomplishment of Ropinirole hydrochloride into brain for the treatment of Parkinsonism. Materials & methods Materials Ropinirole Hydrochloride was obtained as gift sample from Alembic Pvt. Ltd. Baroda, Glycerine from Metro Golden Laboratories, SLS from QFC Fine Chem Industries, Poloxamer 188 (Grade F-68) from Ozone International, Mumbai. All the reagents used were of analytical reagent grade. Methods Preparation of nanoparticles Ropinirole hydrochoride based nanoparticle was prepared by milling technique [5]. 2.1mg of Ropinirole hydrochloride was dissolved in 20ml of mixture of distilled water, glycerin (1%, v/v) and SLS (0.1%, w/v). Poloxamer F-68 (5%, w/v) was added to the above mixture at constant speed of 3500 rpm for 10 minutes in order to get the nanosuspension of Ropinirole hydrochloride. Different concentration of poloxamer F-68 were tried as 2%, 3%, 5% and 7% to develop a stable nanosuspension. The developed nanosuspension was then lyophilized using