A Nanodrop® (Wilmington, USA) Model ND-1000 Spectrophotometer
was used. The spectrophotometer is equipped with a
xenon flash lamp and a 2048-element linear silicon CCD array
detector. The optical path length is 1mm. The sample droplet is
held in place by surface tension when it is slightly compressed
between the drop-supporting surface (pedestal) and the sample
arm. Sample pedestals are made of stainless steel and quartz fiber.
The spectrum measurement is performed with two optical fibers
installed in the pedestal (emitting light of a Xenon lamp) and the
sample arm (spectrometer with linear CCD array). A schematic diagram
of the deposition of the enriched microdrop on the pedestal
of the microvolume UV–vis spectrophotometer for measurement
after HS-SDME is depicted elsewhere [5]. Absorption peak measurements
were carried out at 295 nm.
Headspace single-drop microextraction was performed with a
commercially available 10-L syringe containing a guided-PTFE
plunger (Hamilton model 1701 RN, 10 AL). Iodine generation was
carried out in a 40mL amber-vial with a silicone rubber septum.
A domestic microwave oven, Samsung, Model M 9245 (Seoul,
South Korea), with a 2450MHzmicrowave frequency and an output
power of 1000W was used for pre-treatment of aqueous samples
prior to iodate determination.