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Targeted therapy using magnetic microparticles and nanoparticles has the potential to mitigate the negative side-effects associated with conventional medical treatment. Major technological challenges still need to be addressed in order to translate these particles into in vivo applications. For example, magnetic particles need to be navigated controllably in vessels against flowing streams of body fluid. This paper describes the motion control of paramagnetic microparticles in the flowing streams of fluidic channels with time-varying flow rates (maximum flow is 35 ml.hr−1). This control is designed using a magnetic-based proportional-derivative (PD) control system to compensate for the time-varying flow inside the channels (with width and depth of 2 mm and 1.5 mm, respectively). First, we achieve point-to-point motion control against and along flow rates of 4 ml.hr−1, 6 ml.hr−1, 17 ml.hr−1, and 35 ml.hr−1. The average speeds of single microparticle (with average diameter of 100 μm) against flow rates of 6 ml.hr−1 and 30 ml.hr−1 are calculated to be 45 μm.s−1 and 15 μm.s−1, respectively. Second, we implement PD control with disturbance estimation and compensation. This control decreases the steady-state error by 50%, 70%, 73%, and 78% at flow rates of 4 ml.hr−1, 6 ml.hr−1, 17 ml.hr−1, and 35 ml.hr−1, respectively. Finally, we consider the problem of finding the optimal path (minimal kinetic energy) between two points using calculus of variation, against the mentioned flow rates. Not only do we find that an optimal path between two collinear points with the direction of maximum flow (middle of the fluidic channel) decreases the rise time of the microparticles, but we also decrease the input current that is supplied to the electromagnetic coils by minimizing the kinetic energy of the microparticles, compared to a PD control with disturbance compensation.

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Salbutamol (Sl), also known as albuterol, selective PVC membranes based on ion associates of salbutamolium phosphotungstate (Sl-PTA), salbutamolium phosphomolybdate (Sl-PMA) or a mixture of both (Sl-PTA/PMA) were prepared. The electrodes displayed a linear response over the concentration range 6.3 3 10 26 -1.0 3 10 21 mol dm 23 salbutamol sulfate (Sl 2 SO 4 ). The working pH ranges of the above electrodes were 2.5-11.0, 3.0-11.0 and 2.5-10.5 and their isothermal temperature coefficients were 0.00095, 0.00105 and 0.00136 V °C21 , respectively. The electrodes showed good selectivity to salbutamolium ion with respect to many inorganic cations, sugars and amino acids. The standard additions method was used to determine Sl 2 SO 4 in pure solutions and pharmaceutical preparations with high accuracy and precision.

A new validated potentiometric method is described for batch and continuous quality control monitoring of the drug oseltamivir phosphate (Taminil) (OST). The method involves the development of a potentiometric sensor responsive to the drug based on the use of the ion‐association complex of (OST+) cation with phosphomolybdate anion (PMA−) as an electroactive material in a poly(vinyl chloride) matrix membrane plasticized with o‐nitrophenyloctyl ether (o‐NPOE). Optimization of the performance characteristics of the sensor is described. A membrane incorporating the OST‐PMA‐NPOE complex in a tubular flow through detector is used in a two channel flow injection set up for continuous monitoring of the drug at a frequency of ∼30 samples h−1. The sensor shows fast near‐Nernstian response for OST over the concentration range 5.2×10−5–0.8×10−2 M (21.34 µg mL−1–3.23 mg mL−1) with a detection limit of 9.1×10−6 M (3.73 µg mL−1) over the pH range 4.6–6.1. The sensor displays good selectivity for OST drug over some basic drugs, inorganic cations, excipients and diluents commonly used in the drug formulations. Validation of the assay method is tested by measuring the lower detection limit, range, linearity, bias, trueness, accuracy, precision, and between‐day‐variability, within day reproducibility, selectivity and ruggedness (robustness). The results reveal good potentiometric performance of the proposed sensor for determination of OST in pharmaceutical capsules and in biological fluid matrices as well as for testing the dissolution profile of the drug and drug homogeneity.