International Journal of Pharmaceutics 242 (2002) 335 – 339 Note Caffeine microparticles for nasal administration obtained by spray drying C. Sacchetti, M. Artusi *, P. Santi, P. Colombo Department of Pharmacy, Uniersity of Parma, Parco Area delle Scienze 27 /A, Parma, Italy Received 14 January 2002; received in revised form 18 January 2002; accepted 4 February 2002 Abstract This study investigated the possibility to use spray drying technique to prepare powders formulations containing caffeine intended for nasal delivery. Spray dried powders containing caffeine and excipients, as filler and shaper agents, were prepared. Powders were investigated for particle size, morphology and delivery properties from Monopowder P ® nasal insufflator, assessing the influence of each excipient on microparticles characteristics. The results showed that the excipients strongly affected microparticle properties. Size, shape and agglomeration tendency are relevant characteristics of spray dried nasal powder. © 2002 Elsevier Science B.V. All rights reserved. Keywords: Nasal powders; Caffeine; Spray drying; Nasal insufflator www.elsevier.com/locate/ijpharm Caffeine is a methylxanthine that stimulates the central nervous system, creating a condition of wakefulness and increased mental activity. Re- cently, there has been evidence of the role of caffeine as antagonist of adenosine A 2A receptors in preventing neurodegenerative disorders, such as Parkinson’s disease (Chen et al., 2001). The nasal administered caffeine can target the brain taking advantage of olfactory pathways. Microparticles are a suitable dosage form for insufflation into nasal cavity. Spray drying is one step process transforming liquid into a dried particulate form. The application of spray drying to pharmaceu- ticals includes dry powders for aerosol formula- tion and processing of heat sensitive materials (Broadhead et al., 1992). Qualitative and quanti- tative composition of liquid feed and drying con- ditions strongly affects properties of the spray dried particles such as size, morphology, density, shape, porosity and flowability (Arshady, 1993; Maa et al., 1997; Billon et al., 2000; Esposito et al., 2000). Usually, spray dried powders are made of almost spherical and amorphous microparticles (Vidgre ´n et al., 1987), with a range of median diameter between 2 and 20 m and a narrow size distribution (Broadhead et al., 1992). Nasal deliv- ery requires microparticles that allow a repro- ducible dose reservoir filling and aerosolization for appropiate nasal deposition. * Corresponding author. Tel.: +39-052-190-5083; fax: + 39-052-190-5085 E-mail address: mariella.artusi@unipr.it (M. Artusi). 0378-5173/02/$ - see front matter © 2002 Elsevier Science B.V. All rights reserved. PII:S0378-5173(02)00177-1