PMC

The figure shows the time duration worms spend in each active and immobilization periods until they are permanently immobilized. Each pair of active and immobilization periods is numbered sequentially in the y-axis.

The dose response of C. elegans (represented as the percentage of worms responsive to electrical fields) is plotted for the four drugs used: pyrantel, levamisole, methyridine, and tribendimidine.

The figure shows the probability of a worm being active during the length of drug exposure. The median of time durations for active and immobilized periods are calculated from Figure . The probability of a worm being active is denoted as 1 while that of being immobilized is denoted as 0.

Mode transitions between crawling, curling, and flailing. (a) Snapshots of representative worms during curling (head coiled to or beyond the tail), crawling (sinusoidal movement), and flailing (swimming movement with no net displacement). (b) Boxplot representations of the transition frequency (rate of switching between crawling, curling, and flailing) within 30 s (left), 60 s (middle), and 120 s (right) from the time of entering the drug well.

Body curls in actively moving C. elegans upon exposure to anthelmintics. (a) Snapshots of a representative worm (every 500 ms) as it curls its body such that the head touches or overlaps its tail. (b) Frequency of body curls (i.e., the number of curls divided by the total time a worm stays active) is plotted for the four drugs and control conditions (i.e., in 0.8% agarose gel and DMSO).

Immobilization patterns leading to paralysis. (a) Snapshots of a representative worm undergoing periods of being active and temporarily immobilized. A custom worm tracking program is used to mark the x-y co-ordinates of the worm's body centroid as a function of time (shown in red). (b) The plot shows the percentage of worms that are active (shaded as checkerboard), temporarily immobilized (shaded as horizontal lines), or permanently immobilized (shaded as solid) at the end of 40 min of drug exposure.

Images of the experimental setup. (a) A stereozoom microscope with a computer-controlled camera is used to record and analyze real-time videos of worms in microfluidic devices. (b) Snapshot of a microfluidic chip comprising multiple devices fabricated in PDMS polymer and bonded to a glass slide. (c) A magnified image of a single microfluidic device comprising a straight microchannel that merges into a circular drug well through a tapered mouth. The empty device (left) is first filled with 0.8% agarose gel (mixed with yellow food dye here) and worms are allowed to enter through the input port (middle). Thereafter, the drug solution in agarose gel (mixed with blue food dye here) is filled in the drug well (right).