Dissolved nitrate was analyzed in supernatant using a Seal analytical AQ2 nutrient analyzer (SEAL Analytical Inc., USA) according to the manufacturer's instructions.
In addition, water samples were filtered through a 1-μm glass fiber filter (Millipore Cat. No. AP4004700), chilled on ice, and stored at −20°C until they were analyzed for nitrate using an auto-analyzer (Bran+Luebbe Technicon II with colorimeter; Bran+Luebbe, Buffalo Grove, IL).
Nitrates and ammonium were analyzed on a flow-injection analyzer (Lachat); the nitrates were analyzed using cadmium reduction [ 66] and the ammonium was analyzed using the salicylate method [ 67].
Suspension aliquots of 10 ml were sampled at 2, 4, 22 and 24 h incubation, respectively, and immediately analyzed on the continuous flow analyzer to determine their nitrate concentrations.
Nitrate content was measured directly using Autoanalyzer/Photometric Analyzer, Aquakem250 (Thermo Scientific, Vantaa, Finland).
Next, the liquid was centrifuged at 10,000 rpm for 10 minutes and the supernatant was analyzed for COD (by closed reflux method using dichromate), ammonia, nitrite, and nitrate nitrogen by using an expandable ion electrode analyzer (Orion EA 940, Thermo Fisher Scientific, USA).
The nitrate concentrations were determined by a Sievers Nitric Oxide Analyzer 280i (Analytix Ltd ,UK) according to the manufacturer's instructions.
We have developed a method for quantitating corneal neovascularization, induced in anesthetized rats by silver nitrate/potassium nitrate cauterization, using a LeMont OASYS video input image analyzer.
Total ammonia, phosphate, silicate, and nitrate plus nitrite were determined using a Quattro Auto Analyzer (Seal Analytical, WI, USA).
Their intrinsic nitrate content was measured by chemiluminescence in a Sievers analyzer (model 280; Sievers Instruments, Inc., Boulder, CO, USA) with VCl3 and HCl (at 95°C) as reductants.
