Development of Suspended Droplet Microextraction Method for Spectrophotometric Determination of Serum Iron

A new method using suspended droplet microextraction (SDME) has been developed for the quantification of Fe³⁺ in low volume samples like bovine serum. The process involves forming a red-colored ferric thiocyanate complex, which is extracted into a micro droplet of octanol and then solubilized in methanol for spectrophotometric analysis at 505 nm. The method demonstrated high recovery rates (96.2%-98.8%) and low relative standard deviation (1.4%-5.0%) for Fe³⁺ concentrations ranging from 100-400 ng/mL, with a detection limit of 2.4 ng/mL. It was validated against electrothermal atomic absorption spectrometry, showing accurate results at a 99% confidence level. This method is advantageous due to its enhanced sensitivity, low cost, minimal sample volume requirement, and resistance to interference, making it a viable alternative for routine analysis of serum and other biological fluids.