Page:NIOSH Manual of Analytical Methods - 5041.pdf/1

 CAPSAICIN and DIHYDROCAPSAICIN (1) C18H27NO3 MW: (2) C18H29NO3

305.40 307.48

METHOD: 5041, Issue 1

CAS: 404-86-4 19408-84-5

EVALUATION: PARTIAL

OSHA : no PELs NIOSH: no RELs ACGIH: no TLVs

5041

PROPERTIES:

RTECS: RA8530000 RA5998000

Issue 1: 15 May 1996 (1) white solid; MP 65 C; BP 210-220 C @ 0.01 mm Hg; VP not significant @ 25 C (2) white solid; VP not significant @ 25 C

NAMES & SYNONYMS: (1) capsaicin: trans-8-methyl-N-vanillyl-6-nonenamide (2) dihydrocapsaicin: 8-methyl-N-vanillylnonanamide

SAMPLING SAMPLER:

FILTER (13-mm glass fiber)

MEASUREMENT TECHNIQUE:

HPLC, FLUORESCENCE DETECTOR

ANALYTES:

capsaicin and dihydrocapsaicin 2 mL acetonitrile; ultrasonic bath, min

FLOW RATE:

1 to 3 L/min

EXTRACTION:

VOL-MIN:

(1) 5L @ 0.01 mg/m3 (2) 7 L @ 0.01 mg/m3 1000 L

INJECTION VOLUME:

SHIPMENT:

ship at 0 C

MOBILE PHASE:

48% acetonitrile/52% water v/v; mL/min

SAMPLE STABILITY:

at least 26 days @ 5 C [1,2]

COLUMN:

3.9-mm ID x 15 cm stainless steel packed with 10-µm µ-Bondapak C18

BLANKS:

2 to 10 field blanks per set DETECTOR:

fluorescence: excitation 281 nm; emission 312 nm

CALIBRATION:

standard solutions of capsaicin and dihydrocapsaicin in acetonitrile

RANGE:

(1) 0.050 to 100 µg/sample (2) 0.067 to 100 µg/sample

ESTIMATED LOD:

(1) 0.015 µg/sample (2) 0.02 µg/sample

PRECISION ( r):

(1) 0.042 @ 0.13 to 17 µg/sample (2) 0.065 @ 0.11 to 3 µg/sample

-MAX:

ACCURACY RANGE STUDIED:

not studied

BIAS:

not determined

OVERALL PRECISION ( ACCURACY:

rT

):

10

25 µL 1

not determined not determined

APPLICABILITY: This method has been used to analyze samples collected at a pickle and pepper processing plant [1]. Analyte concentrations in sample solutions are not expected to exceed 0.2 µg/mL when samples are collected in this type of environment. INTERFERENCES: Capsaicin and dihydrocapsaicin exhibit baseline separation at concentrations of 0.2 µg/mL and less. At higher concentrations, baseline separation can be achieved by increasing the water in the mobile phase to about 55%. Nordihydrocapsaicin causes little interference during measurement of capsaicin because its abundance is relatively small in Capsicum fruit [3].

OTHER METHODS: HPLC methods for one or both analytes in solution have been published [3-8]. None have been published for air analysis.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 5/15/96