Tungsten Trioxide (WO₃) has different morphologies and structures at different temperatures. WO₃ has at least five structural phase transitions between -40 and 740 degrees Celsius, and the hexagonal phase is a stable morphological structure between 200 and 400 degrees Celsius.

Platinum (Pt) and Pt alloy electrocatalysts supported on carbon (Pt/C) are the best catalysts for methanol oxidation in direct methanol fuel cells (DMFC). However, their high cost hinder the commercialization of DMFC. Recently, due to the strong synergy between metal oxides and Pt, people have focused their attention on metal oxides. Among the metal oxides, tungsten trioxide (WO3) has special electrochemical properties and can be used as an electrocatalyst carrier.

Theophylline (THP) is used to treat patients with reversible airway obstruction (asthma and chronic obstructive pulmonary). It relaxes smooth muscles, opens the airways of the lungs, and makes breathing easier. Therefore, it is of great significance to develop an accurate, simple and fast method to measure theophylline in different media.

Progesterone (PGT) are important hormone and it is endogenous-steroid and female sex hormone involved in the pregnancy, menstrual cycle, and embryogenesis of humans. Therefore, sensitive, and rapid detection of low concentrations in biological fluids has become increasingly important.