A (970), A (723) and A (2236) are the
absorbances of the corresponding bonds.
In the [DELTA][A.sub.450] (or [DELTA]O[D.sub.450]) method, the
absorbance at 450 run is used as a surrogate for concentration of amniotic bilirubin.
A 33% decrease in the maximum
absorbance value ([A.sub.max]) was observed between the standard curve and the 1:100 milk standard curve, indicating a matrix effect in milk, along with the lowered E[C.sub.50].
However, owing to contamination by noise, the
absorbance data measured at the range of 1600 to 1800 nm, where the amplitude of intensity is larger than 2.0, is less reliable.
Wavelengths of maximum
absorbance ([[lambda].sub.max]) and protein concentrations were determined spectrophotometrically (Pharmacia Ultrospec III and Autofill III; Whitaker and Granum, 1980).
For DE monitoring, the instrument is simply "tuned" to measure the
absorbances of the selected entity.
In order to maximize the amount of the emitted fluorescence (for nonsaturating illumination), the fluorescence quantum yield and the fluorescence
absorbance have to be as large as possible [6].
The final concentrations used for taking the
absorbance are 0.25 mg, 0.50 mg, 0.75 mg, 1.00 mg, 1.25 g, 1.5 mg, 1.75 mg, 2.00 mg, 2.25 mg, and 2.5mg per ml.
In summary, use of photodegradation with a routinely available slide projector as the light source enables the
absorbance attributable to bilirubin to be determined even in specimens containing high
absorbances of the other pigments commonly seen in amniotic fluid contaminated with blood.
Films were extracted in acetone to remove unreacted coagent, IR spectra were recorded, and vibrations of
absorbances of the s-triazine ring at 821 [cm.sup.-1] and at 1566 [cm.sup.-1] were measured.
Where: As,t-X h and As,t-0 h are the
absorbances of the sample at X h and 0 h, respectively; and A0,t-X h and A0,t-0 h are the
absorbances of the blank at X h and 0 h, respectively.
Difference in
absorbances of SAD at 240.4 and 286.4 nm were plotted against its concentration in the range of 2-20 g ml-1 also for ASC difference in
absorbances at 249.8 and 285.8 nm were plotted against its concentration in the range of 2-20 g ml-1.
To prospectively identify samples with the interference seen in the index case, we used open channels on the Hitachi 917 analyzer and manually programmed the analyzer to create a flag that was triggered when the difference between the
absorbances at measurement points 12 and 14 (216 and 252 s, respectively) was >0.035.
Subsequently, the
absorbance at 360 nm was set to 1.0, and the
absorbances at 405, 414, and 455 nm were converted into relative
absorbance values.
