ALGAE DETECTION AND SHIP'S BALLAST WATER ANALYSIS BY A MICROFLUIDIC LAB-ON-CHIP DEVICE

This article reports a microfluidic lab-on-chip device that can detect algae and analyze ship's ballast water treatment performance according to the standard set by the International Convention for the Control and Management of Ships' Ballast Water and Sediments. A microfluidic differential resistive pulse sensor (RPS) was employed to detect, count, and size two algae of different sizes, a larger alga, Pseudokirchneriella subcapitata, and a smaller one, Chlorella vulgaris. The number rate of the algae flowing through the sensing gate per 2 min is a linear function of the sample concentration. A number rate-concentration correlation curve was experimentally obtained and verified, and can be used to determine the algae concentration simply by counting the number of peaks within several minutes. This lab-on-chip device described in this article is sensitive enough to detect the algae killing efficiency by electrolysis treatment to the ballast water. Also, this device can be easily operated by nonprofessionals and thus has great potentials in shipboard on-site testing for port state control.