L lactic acid

L-lactic acid and hydroxymethylferrocene were obtained from Tokyo Chemical Industry Co., Ltd. (Tokyo, Japan). Phosphate buffer solution (PBS) (0.1 mol/L, pH 7.0) was purchased from the Nacalai Tesque, Inc. (Kyoto, Japan). L-LOx (LCO-301) was purchased from the Toyobo Corp. (Osaka, Japan). Water for molecular biology (H20MB0501) was obtained from Merck KGaA (Darmstadt, Germany). Water-soluble photocurable photosensitive resin (BIOSURFINE-AWP) was obtained from Toyo Gosei Co., Ltd. (Tokyo, Japan). Methanol was obtained from FUJIFILM Wako Pure Chemical Corporation (Osaka, Japan). The original printing electrode chip (DEP-CHIP) was procured from Bio-Device Technology, Inc. (Ishikawa, Japan).

Poly-l-lysine (PLL) hydrobromide (molecular weight (MW): 4000–15,000 Da), poly-(d, l)-Lysine (PDLL) hydrobromide (MW:25,000–40,000 Da), and 2,6-dichloroindophenol sodium salt hydrate (DCIP) were obtained from Sigma-Aldrich Co. (MO, USA). NaCl was obtained from Kanto Chemical Co., Inc. (Tokyo, Japan). Tris(hydroxymethyl)aminomethane, acetaldehyde (Tris), and glucose were obtained from Nacalai Tesque (Kyoto, Japan), and 2-morpholinoethanesulfonic acid monohydrate (MES) was obtained from Dojindo Laboratories (Kumamoto, Japan). l-lactic acid, d-lactic acid, and pyruvic acid were obtained from Tokyo Chemical Industry Co., Ltd. (Tokyo, Japan).

Biogents (BG)-lure. BG-lure (Biogents, Regensburg, Germany) purchased from BioQuip (Rancho Dominguez, CA, USA) contains a mixture of at least three active ingredients: 20–40% L-(+)-lactic acid, 20–40% ammonium hydrogen carbonate, 5–10% hexanoic acid, and other inert ingredients.
Kasetsart University (KU)-lure candidates. Six KU-lure candidates with different chemical compositions were investigated. Four mixtures contained L-lactic acid (Tokyo chemical industry Co., LTD., Tokyo, Japan) and isovaleric acid (Sigma-Aldrich, St. Louis, MO, USA) in various proportions (% w/v). For example, KU-lures #1 and #6 consisted of the same ingredients, but the latter had lower concentrations. KU-lures #4 and #5 were based on the same concentration of lactic acid, but the former was mixed with two more compounds: ammonium hydroxide and myristic acid. KU-lures #2 and #3 are single compounds of isoamyl alcohol and octanol, respectively (Table 1).
Based on the results of tests to determine the optimal dose, we used KU-lure #1 for Ae. aegypti and KU-lure #6 for Cx. quinquefasciatus for further studies.