br Experimental br Results and discussion Fig shows schemati

Experimental
Results and discussion Fig. 2 shows schematically the fundamentals of the developed HRP-P4-(P4)-anti-P4-Protein-G-MBs/SPCE immunosensor. Oriented immobilization of anti-P4 was accomplished onto Protein G-MBs due to the Protein G binding ability with the Fc region of many mammals immunoglobulins. Thereafter, a direct competitive immunoassay involving P4 and HRP-P4 was implemented. Monitoring of the affinity reaction was carried out amperometrically by adding H2O2 in the presence of HQ as the redox mediator.
Conclusions A novel device for the determination of P4 in undiluted saliva is reported here. The device couples the use of a disposable immunosensor involving functionalized MBs on which a direct competitive immunoassay is implemented, and amperometric detection at SPCEs using a COTS-based potentiostat. The immunosensor exhibits an attractive analytical behavior providing a low LOD of 5 pg mL−1 and high selectivity. No significant differences were found between the analytical performance achieved by performing the amperometric transduction using the conventional potentiostat, and the developed COTS-based potentiostat. The obtained results demonstrate the usefulness of the immunosensor-COTS-based potentiostat device for the simple, fast (45 min) and accurate determination of the endogenous P4 content in undiluted saliva samples from individuals in different situations related to fertility and menopause. Moreover, the possibility of transferring the developed methodology to the determination of other steroid K-252c together with the unique features offered by the developed potentiostat in terms of cost, portability and versatility make the reported strategy particularly attractive for integration in cost-efficient devices appropriate to perform at different settings simple, quick, and routine determinations of relevant analytes in minimally invasive but challenging samples.
Introduction Software, omnipresent around us, may be acquired through different ways, basically purchased. Indeed, recent studies carried by “Gartner” in March 2014 and “Syntec Numérique” in October 2015 show that worldwide software market is continuously growing with an annual average of 4% from 2013 to 2016. In terms of value, this is represented, for example and according to Gartner, by an increase of business software market ranging from 2 billion dollars to 10 billion dollars during the same period. Most of the purchased software is of a special type known as Commercial-Off-The-Shelf (COTS). A COTS component, as defined by the Software Engineering Institute, is “a software product that is: (1) sold, leased, or licensed to the general public, (2) offered by a vendor trying to profit from it, (3) supported and evolved by the vendor, who retains the intellectual property rights, (4) made available in multiple, identical copies, and (5) used without source code modification by a consumer” (Meyers and Oberndorf, 2001). COTS components are a class of reusable software components (Ayala and Franch, 2006). These latter differ from objects in that morphological convergence are not fine-grained units of composition (Wang and Qian, 2005). They come in different shapes and sizes ranging from small components that can be traded online to large grained ones containing extensive functionalities and including a company’s business logic (Wang and Qian, 2005). Specifically, COTS components are usually coarse-grained components (Brown and Wallnau, 1998) that satisfy high-level requirements by integrating several services and offering several interfaces (Iribarne, Troya, Vallecillo, 2004, Iribarne, Troya, Vallecillo, 2006). They usually live in software repositories and may range from simple libraries which provide a limited and clear set of functions, to components whose functionality is so broad and complex such as Web servers and database management systems (Carvallo, 2005).