Micro-channels　that　contain　a　special　inner　structure　are　critical　for　efficient　mixing　and　chemical　reactions.　In　this　paper,　we　described　the　facile　fabrication　of　an　integrated　microchip　with　double-helix　type　micro-channels　to　improve　mixing　efficiency　and　to　facilitate　multi-step　derivatization　reactions　prior　to　electrophoretic　separation.　With　a　prepared　microchip,　reagents,　samples　and　reaction　products　could　be　driven　through　micro-channels　by　siphon,　and　no　other　pumping　device　was　necessary.　To　test　its　performance,　reductive　amination　of　aldehydes　with　8-aminonaphthalene-1,3,6-trisulfonate　acid　disodium　(ANTS)　was　attempted　via　microchip　electrophoresis　with　laser　induced　fluorescence　(LIF).　The　effect　of　the　geometry　of　the　reaction　micro-channel　on　the　reaction＇s　efficiency　was　evaluated.　Under　the　selected　conditions,　successful　derivatization　of　five　aldehydes　was　realized　for　highly　reproducible　analysis.　The　relative　standard　deviations　of　the　peak　areas　for　30　consecutive　injections　were　in　the　range　of　0.28-1.61%.　The　method　was　applied　for　the　determination　of　aldehydes　in　real　samples　with　standard　addition　recoveries　of　87.8-102.8%.　Good　tolerance　of　organic　solvents　was　achieved,　and　the　proposed　method　can　potentially　be　employed　for　rapid　screening　of　excessively　added　aldehyde　food　flavoring.　(C)　2015　Elsevier　B.V.　All　rights　reserved.