OPTIMedical OPTI CCA-TS - Page 185

Operator’s Manual – OPTI CCA-TS pH-B-3
ANALYTES pH (Dry Sensor)
The following samples were identied as interfering with the dry pH sensor in the interference study
performed for the OPTI LION 510(k) submission.
Interferent Test Level Change
Sodium Bisulphate 11.5mM -0.16
Phenylacetic Acid 10.0mM -0.12
Methylene Blue 25mg/dL Unstable
Fluorescein 25mg/dL Unstable
Reproducibility
Controls
Within-Run (Swr) and Total (ST) Precision were determined from 2 runs per day with 2 replicates per run
over a period of 20 days following the CLSI guideline EP5-A2. Typical results for three different lots of
B-Lac cassettes are shown below.
Material mean Lot 1 Lot 2 Lot 3
OPTI CHECK
(aqueous control solution)
Swr ST Swr ST Swr ST
Level 1 7.17 0.011 0.014 0.008 0.007 0.005 0.006
Level 2 7.44 0.010 0.010 0.010 0.010 0.004 0.005
Level 3 7.65 0.011 0.011 0.007 0.007 0.004 0.006
Whole Blood
Within-Run precision in whole blood samples was evaluated at three different pH concentrations using
multiple instruments and multiple cassette lots.
pH in Whole Blood
Level 1 Level 2 Level 3
Average 7.170 7.306 7.610
St. Dev 0.008 0.007 0.011
%CV 0.12% 0.10% 0.14%
n 18 18 18
Linearity
3
Wherever possible, linearity for the OPTI CCA-TS measurement has been established against reference
materials or methods. The linearity of the dry pH sensor has been established versus the standard
pH sensor which is already approved for use on the OPTI CCA-TS system. Whole blood samples
tonometered with different %CO
2
gas mixtures were used to establish the correlation.
LinearityofWholeBloodSamples
 Slope Intercept R
2
 Sy.x  Range  n
0.99 0.09 0.996 0.016 6.59-7.86 189