[11C]PBR 28 FOR INJECTION: STANDARD OPERATING
PROCEDURES
PET Radiopharmaceutical Sciences Section,
Molecular Imaging Branch,
National Institute of Mental Health,
National Institutes of Health,
Bldg. 10, Rm. B3 C338,
Bethesda, MD 20892
Date of review: 09/20/05
Data record for SOP # QA307
Standard HPLC Calibration Curve of Reference PBR 28
Purpose: to generate a calibration curve to determine the mass of the carrier in
[11C]PBR 28 for injection
A. Stock solution of reference PBR 28
Weigh an accurate mass of PBR 28 (ca. 3 mg).
Dissolve in acetonitrile in a 10 mL
volumetric flask for QC. Mix thoroughly for several minutes. When not in use, store at 4 ○C
in the refrigerator.
Concentration of solution = ~ 0.3 µg/µL
Date: _______
Balance #: ________
Recorded weight of 1 mg/10 mg serial standard # 2817: 1 mg: _____ 10 mg: ______
Does balance give accurate measure of weight (+/- 5%) based using NIST traceable
standards: Y or N Initials: _______ Checker Initials: _______
Weight of PBR 28 dispensed in ___ mL clean, volumetric flask: _____ mg
Batch # of PBR 28: ___________
Initials: _______ Checker Initials: _______
Concentration of PBR 28 : _______ ug/mL
Initials: _______ Checker Initials: _______
B.
Diluted PBR 28 standard solution
From the stock solution make a dilution 1: 100

Example: take 100 µL of stock solution. Dilute with solvent (HPLC water) to the 10
mL mark of a clean volumetric flask (10 mL size)
Concentration: ~ 3 ng/µL
mol of PBR 28 (M.Wt. = 348.4) in this dilution:
3 ng/348.4 = 8.61 x 10-6 mol in 1.0 µL
Document 9. [11C]PBR 28 for Injection: Standard Operating Procedures
Page 1 of 2
[11C]PBR 28 FOR INJECTION: STANDARD OPERATING
PROCEDURES
PET Radiopharmaceutical Sciences Section,
Molecular Imaging Branch,
National Institute of Mental Health,
National Institutes of Health,
Bldg. 10, Rm. B3 C338,
Bethesda, MD 20892
Date of review: 09/20/05
Mix well to ensure homogeneity. When not in use, store at 4 ºC under refrigeration.
C. Procedure for obtaining standard curve
1. Open the Beckman 32 karat software and select the instrument ”Analysis System”
to start HPLC system.
2. Set the analytical HPLC System (Beckman Coulter) in working conditions and keep
flow for 30 min for column equilibration.
HPLC System conditions:
Column: Onyx Monolithic C-18 (10 μ; 4.6 x 100 mm;
Phenomenex)
Mobile Phase: Acetonitrile-ammonium formate (0.01 M) (30: 70
v/v)
Flow Rate: 6 mL/min.
UV Wavelength: 220 nm
3. Select the method ” pbr28_ONYX_analytical_.met” in method box and check the
instrument setup on the “Instrument Setup” box, then close box.
4. Using the diluted PBR28 standard solution make injections (at least in duplicate)
into the HPLC system varying the injected volume.
5. Recommended mass amounts on column are 50 to 600 ng (10–150 μL).
6. Make two to four injections of each volume.
7. Perform regression analysis on the data, plotting peak area units versus µg.
8. Using the PBR 28 external standard, calculate the slope of calibration line (M), Yaxis intercept of calibration line (b) and correlation coefficient (r2).
9. Following is linear calibration fit of external standards where x = peak area via
computer integration and Y = µg of PBR 28.
The equation for calculating the mass amount of PBR 28 is:
Y = Mx+b. Typically, b is small and can be omitted.
Document 9. [11C]PBR 28 for Injection: Standard Operating Procedures
Page 2 of 2