Microfluidic device, system and methods thereof for measuring and recording electrical signals from a pool of multiple nematodes

Abstract

The present disclosure provides a microfluidic device and system for measuring a composite electropharyngeogram (EPG) signal from a pool of multiple nematodes, wherein the composite EPG signal is measured from the pool of nematodes present in a single recording channel connected to two or more integrated electrodes. The microfluidic device includes an inlet port and outlet port directly connected to a single recording channel and two or more electrodes directly connected to the recording channel. The recording channel is configured to hold 10 to 10,000 nematodes.

1 - 77 . (canceled) 
     
     
         78 . A microfluidic device for measuring a composite electropharyngeogram (EPG) signal from a pool of multiple nematodes comprising:
 a) an inlet port and outlet port directly connected to a single recording channel;   b) the single recording channel, configured to hold 10 to 10,000 nematodes;   c) a filter integrated into the recording channel to retain nematodes in the single recording channel; and,   d) two or more electrodes connected to the recording channel.   
     
     
         79 . The device of  claim 78 , wherein the recording channel is 10 mm to 500 mm in length and 10 μm to 500 μm in width. 
     
     
         80 . The device of  claim 78 , wherein the recording channel is about 10 μm, about 20 μm, about 30 μm, about 40 μm, about 50 μm, about 75 μm, about 100 μm, about 125 μm, about 150 μm, about 175 μm, about 200 μm, about 225 μm, about 250 μm, about 275 μm, about 300 μm, about 325 μm, about 350 μm, about 375 μm, about 400 μm, about 425 μm, about 450 μm, about 475 μm or about 500 μm in width. 
     
     
         81 . The device of  claim 78 , wherein the device comprises a silicone polymer, a thermoplastic polymer, an acrylic polymer, or a polycarbonate polymer. 
     
     
         82 . The device of  claim 81 , wherein the silicone polymer comprises a polydimethylsiloxane (PDMS) elastomer. 
     
     
         83 . The device of  claim 78 , wherein the device comprises a backing. 
     
     
         84 . A microfluidic system for recording a composite electropharyngeogram (EPG) signal from a pool of multiple nematodes comprising:
 a) an inlet port and outlet port directly connected to a single recording channel;   b) a single recording channel, configured to hold 10 to 10,000 nematodes;   c) a filter integrated into the recording channel to retain nematodes in the single recording channel;   d) two or more electrodes connected to the recording channel; and,   e) at least one differential amplifier or at least one voltage-clamp amplifier, wherein the amplifier is connected to an output from the two or more electrodes.   
     
     
         85 . The system of  claim 84 , wherein the differential amplifier or voltage-clamp amplifier is connected to the two or more integrated electrodes via a recording dock. 
     
     
         86 . The system of  claim 84 , wherein the recording channel is 10 mm to 500 mm in length and 10 μm to 500 μm in width. 
     
     
         87 . The system of  claim 84 , wherein the recording channel is about 10 μm, about 20 μm, about 30 μm, about 40 μm, about 50 μm, about 75 μm, about 100 μm, about 125 μm, about 150 μm, about 175 μm, about 200 μm, about 225 μm, about 250 μm, about 275 μm, about 300 μm, about 325 μm, about 350 μm, about 375 μm, about 400 μm, about 425 μm, about 450 μm, about 475 μm or about 500 μm in width. 
     
     
         88 . The system of  claim 78 , comprising a silicone polymer, a thermoplastic polymer, an acrylic polymer, or a polycarbonate polymer. 
     
     
         89 . The system of  claim 88 , wherein the silicone polymer comprises a polydimethylsiloxane (PDMS) elastomer. 
     
     
         90 . A method for recording a composite electropharyngeogram (EPG) signal from a pool of multiple nematodes comprising:
 a) introducing the pool of multiple nematodes into the single recording channel through the inlet port of the microfluidic system of  claim 84 , wherein the pool of multiple nematodes is present in an aqueous buffer solution;   b) measuring electrophysiological signals from the pool of multiple nematodes; and,   c) recording the electrophysiological signals as a single composite EPG.   
     
     
         91 . The method of  claim 90 , wherein the buffer solution comprises serotonin, food, or other stimulant to cause pharyngeal pumping. 
     
     
         92 . The method of  claim 90 , wherein the pool of nematodes comprises transgenic nematodes or transgenic nematodes comprising a gene variant. 
     
     
         93 . The method of  claim 90 , wherein the pool of multiple nematodes is perfused with a second buffer solution. 
     
     
         94 . The method of  claim 93 , wherein the recording step c) is repeated following the perfusion with the second buffer. 
     
     
         95 . A method for screening test compounds by recording a composite electropharyngeogram (EPG) signal from a pool of multiple nematodes using the microfluidic system of  claim 84 , comprising:
 a) contacting the pool of multiple nematodes with the test compound;   b) measuring and recording a composite EPG from the contacted pool of multiple nematodes;   c) comparing the recorded composite EPG to a control composite EPG; and,   d) determining if the recorded composite EPG is altered as compared to the control composite EPG, whereby test compounds are screened.   
     
     
         96 . The method of  claim 95 , wherein determining if the recorded composite EPG is altered comprises determining the power spectrum of the composite EPG, the frequency of the peak power of the composite EPG, the amplitude of the composite EPG, waveform of the composite EPG, or a combination thereof. 
     
     
         97 . The method of  claim 95 , wherein the test compound is selected from a drug, a drug candidate, an industrial chemical, or an environmental pollutant.