Inkjet printing as a tool for the patterned deposition of octadecylsiloxane monolayers on silicon oxide surfaces.

We present a case study about inkjet printing as a tool for molecular patterning of silicon oxide surfaces with hydrophobic functionality, mediated by n-octadecyltrichlorosilane (OTS) molecules. In contrast to state-of-the-art techniques such as micro contact printing or chemical immersion with subsequent lithography processes, piezo drop-on-demand inkjet printing does not depend on physical masters, which allows an effective direct-write patterning of rigid or flexible substrates and enables short run-lengths of the individual pattern. In this paper, we used mesithylene-based OTS inks, jetted them in droplets of 10 pL on a silicon oxide surface, evaluated the water contact angle of the patterned areas and fitted the results with Cassie's law. For inks of 2.0 mM OTS concentration, we found that effective area coverages of 38% can be obtained. Our results hence show that contact times of the order of hundred milliseconds are sufficient to form a pattern of regions with OTS molecules adsorbed to the surface, representing at least a fragmented, inhomogeneous self-assembled OTS monolayer (OTS-SAM).

Prevalence and safety-relevance of drug-related problems in German community pharmacies.

PURPOSE: The purpose of this study was to assess prevalence and characteristics, including safety-relevance, of drug-related problems (DRPs) detectable in community pharmacy routine service, and to investigate the influence of relevant risk factors. METHODS: Patients in 69 community pharmacies in Berlin were surveyed using a checklist for quality assurance of DRP detection in order to enable quantitative detection. An expert committee assessed the safety-relevance of detected DRPs by use of an algorithm. Logistic regression analysis was applied to investigate the influence of different risk factors. RESULTS: Of the 3040 surveyed patients, 638 (21.0%) were affected by DRPs. Among these, 455 (71.3%) had problems of low, 170 (26.6%) of significant and 13 (2.0%) of high safety-relevance. Significant risk factors identified were self-medication and new medication, especially new prescriptions. Age, gender and the number of dispensed drugs had little influence on occurrence of DRPs. The two major groups of DRPs were therapeutic errors, often correlating with self-medication, and information problems, often correlating with new medications. Drug classes most frequently associated with DRPs were analgesics/NSAID, antibiotics, nasal preparations and cough medications. CONCLUSION: DRPs are frequent among patients in German community pharmacies. Advanced research in this field (DRP-pharmacovigilance) and implementation of methods for quality assurance of pharmaceutical counselling, that is exhaustive DRP detection, may improve the safety of drug therapies significantly. In particular, pharmaceutical counselling is an important instrument for assuring treatment appropriateness and safety of OTC drugs.