A new support has been proposed to be used for carrier-mediated electromembrane extraction purposes. The new support (Tiss (R)-OH) is a 100 mu m thickness sheet nanofiber membrane manufactured by electrospinning and composed by acrylic nanofibers. It has been used in an electromembrane extraction (EME) combined with a HPLC procedure using diode array detection. The proposed method has been used for the extraction of four high polarity acidic compounds: nicotinic acid, amoxicillin, hippuric acid and salicylic acid. Analytes were extracted from an aqueous sample solution (pH 4) (donor phase) using a Tiss (R)-OH sheet that supports a 5% (w/v) Aliquat (R) 336 in 1-octanol liquid membrane. Aqueous solution (pH 6) was used as acceptor phase. The electrical field was generated from a d.c. electrical current of 100 V through two spiral shaped platinum wires placed into donor and acceptor phases. Analytes were extracted in 10 min with recoveries in the 60-85% range. The proposed EME procedure has been successfully applied to the determination of the target analytes in human urine samples.