Journal of Pharmaceutical and Biomedical Analysis 27 (2002) 217–224 Simple and rapid determination of psoralens in topic solutions using liquid chromatography Cla ´udia A. L. Cardoso a, *, Neli K. Honda b , Andersson Barison b a Uniersidade Estadual de Mato Grosso do Sul, Caixa Postal 351, 79804 -970, Dourados, MS, Brazil b Departamento de Quı ´mica, Uniersidade Federal de Mato Grosso do Sul, Caixa Postal 649, 79070 -900, Campo Grande, MS, Brazil Received 23 April 2001; received in revised form 13 June 2001; accepted 10 July 2001 Abstract A method for sample preparation and high-performance liquid chromatography detection and quantification has been developed for the routine analysis of psoralen and bergapten, photosensitizing compounds, in topic solutions employed in Brazil for treatment of vitiligo and psoriasis. The linearity, accuracy, the inter- and intra-day precision of the procedure were evaluated. The calibration curve for psoralen and bergapten were linear in the range 1.0 – 20.0 g ml -1 . The best recoveries of the psoralens in the topic solutions analysed were 96.3 – 98.2%. The percentage coefficient of variation of the quantitative analysis of the psoralens in the product analyses was within 5%. © 2002 Elsevier Science B.V. All rights reserved. Keywords: Liquid chromatography; Psoralens; Furanocoumarins; Quantification www.elsevier.com/locate/jpba 1. Introduction Psoralens or furanocoumarins are well known photoreactive compounds [1], psoralen and bergapten (Fig. 1) are used in some pharmaceuti- cal and cosmetic products because of their UV light absorbing properties [2]. Psoralens are also increasingly used in dermatology for the pho- tochemotherapy of diseases such as vitiligo, psori- asis, mycosis fungoides, atopic eczema and alopecia areata among others [3,4]. The biological activity of these compounds are attributable to their ability to intercalate into DNA, where they form mono and di-adducts in the presence of long-wave UV light [5]. Furthermore, the use of psoralens in medicine has been associated with higher incidence of skin cancer [6,7]. Linear pso- ralens cause phototoxicity [8,9]. Several studies have demonstrated that the psoralens are carcino- genic, mutagenic and photodermatitic [10,11]. The psoralens are currently employed in derma- tology (orally or topically), associated with Ultra- violet A (UVA) irradiation. The combination of these previous compounds with UVA irradiation is known as PUVA therapy (Psoralens plus UVA irradiation) [12 – 14]. * Corresponding author. E-mail address: claudia@uems.br, acardoso@nin.ufms.br (C.A.L. Cardoso). 0731-7085/02/$ - see front matter © 2002 Elsevier Science B.V. All rights reserved. PII:S0731-7085(01)00537-4