A highly sensitive HPLC method was developed for the determination of xenoestrogenic compound, bisphenol A (BPA) in human breast milk samples. After a two-step liquid-liquid extraction, BPA was derivatized with fluorescent labeling reagent, 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride (DIB-Cl). The excess fluorescent reagent could be removed effectively using a column-switching system. The separation of DIB-BPA from endogenous materials in milk was carried out on two C(18) columns and fluorescence intensity was monitored at 475 nm with the excitation of 350 nm. A good linearity (r = 0.994) was observed of BPA in the concentration range of 0.2-5.0 ng mL(-1) in breast milk, and the detection limit was 0.11 ng mL(-1) at a signal-to-noise ratio of 3. Intra- and inter-day precision (RSD, %) were less than 8.7 and 10.4, respectively. Twenty-three breast milk samples of healthy lactating women were analyzed for the BPA concentration; the mean value was 0.61 +/- 0.20 ng mL(-1), with no correlation to the lipid content of milk samples.

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Hair has been focused on for its usability as an alternative biological specimen to blood and urine for determining drugs of abuse in fields such as forensic and toxicological sciences because hair can be used to elucidate the long intake history of abused drugs compared with blood and urine. Hair analysis consists of several pretreatment steps, such as washing out contaminates from hair, extraction of target compounds from hair, and cleanup for instrumental analysis. Each step includes characteristic and independent features for the class of drugs, e.g., stimulants, narcotics, cannabis, and other medicaments. In this review, recently developed methods to determine drugs of abuse are summarized, and the pretreatment steps as well as the sensitivity and applicability are critically discussed.

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Pandanus conoideus is an endemic plant of Papua, Indonesia, reported to be very rich in carotenoids. The purpose of this study was to develop method for the determination of carotenoids (α-cryptoxanthin, β-cryptoxanthin, α-carotene and β-carotene) in P. conoideus oil (PO) by high-performance liquid chromatography (HPLC). sing the proposed method in this research, carotenoids content of nine clones of PO were analyzed which ranged from 5.4-138.5 ng/mg for α-cryptoxanthin, 3.9-29.4 ng/mg for β-cryptoxanthin, 3.5-80.0 ng/mg for α-carotene, and 10.8-118.0 ng/mg for β-carotene. Our results showed that four carotenoids content was very small as compared to total carotenoids content (3027-19959 ng/mg). This suggests that those four carotenoids were not a major component of the PO carotenoids. Using the principal component analysis, nine clones of P. conoideus can be grouped based on the proximity of its carotenoid content into group A (Monsor, Mbarugum, Himbiak, Monsrus and Memeri), group B (Menjib Rumbai), and group C (Edewewits, Hibcau and Hityom).