The biosensor based on the pyruvate oxidase modified conducting polymer for phosphate ions determinations

Zirconium immobilized on gold–mercaptopropionic acid self-assembled monolayer for trace determination of phosphate in blood serum by using CV, EIS, and OSWV

“…Electrochemical techniques; like voltammetry based on thin film self-assembled monolayers (SAMs) (Reynes et al, 2008;Aoki et al, 2003), stripping analysis (Lundquist and Cox, 1974), enzyme modified electrode biosensors (Rahman et al, 2006;Mak et al, 2003) and potentiometry based on ion-selective electrodes (Kim et al, 2008), usually enjoy the simplicity, lower price, and better analytical characteristics (Bersier et al, 1994). Besides, the instrumentation is lightweight, compact, easily be taken into the field, and readily be automated (Howell et al, 2003).…”

Recent advances in phosphate biosensors

“…However, to avoid any interference from materials such as ascorbic acid, uric acid, acetaminophenone etc., a preoxidizing cell was incorporated in the system for the oxidation of these species. For same samples, a lower detection limit and response time of 0.3 lM and 6 s, respectively, has been reported for the biosensor fabricated by covalent immobilization of POD onto nanoparticle composed conducting polymers (Rahman et al 2006), with good anti-interference ability to the species mentioned earlier. The advantage of incorporating nanoparticles composed conducting polymers was that it exhibits a high surface area and thus, favors a high enzyme loading.…”

“…In this method, inorganic phosphate reacts with ammonium molybdate to produce phospho-molybdate (reduced), which is measured at 340 nm. However, this method is tedious and time consuming (Kwan et al 2005;Rahman et al 2006). Moreover, use of some carcinogenic chemicals, such as molybdenum, makes this procedure, health hazardous (Zhang et al 2008;Gilbert et al 2011).…”

“…for the catalysis to take place, but these cofactors do not play any role in the selective nature of biosensor (Gavalas and Chaniotakis 2001). The reaction is phosphate-dependent and thus has been applied to develop the biosensor for phosphate estimation in water samples (Kubo et al 1991;Zhang et al 2008;Gilbert et al 2010Gilbert et al , 2011Ogabiela and Adeloju 2014), and biological fluids such as urine (Gilbert et al 2010(Gilbert et al , 2011, serum (Gavalas and Chaniotakis 2001;Rahman et al 2006) and saliva (Kwan et al 2005). An amperometric biosensor was developed by immobilizing POD on cellulose acetate and cellulose nitrate membranes with the help of glutaraldehyde as a cross-linking agent (Gilbert et al 2011).…”

“…The most common disadvantages is that the optimal operating conditions for both the enzymes might be different which further lowers the stability of phosphate biosensor (Rahman et al 2006). Table 2 provides an overview of some of the bi-enzymatic biosensor developed for phosphate estimation.…”