Device and method for detecting chemical and biological agents

Abstract

A device and method capable of sensing the presence of biochem agents, and preferably also capable of delivering precise amounts of one or more antidotes to treat a victim exposed to the agents. The device includes a freestanding tube portion having an internal passage containing a substance selective to a chemical or biological agent so that matter accumulates within the freestanding tube portion when a fluid drawn through the tube portion contains the agent. When vibrated at resonance, the resonant frequency of the tube portion is indicative of the accumulation of matter and thereby the presence of the agent to which the substance is selective. The device then preferably delivers precise amounts of one or more appropriate antidotes to treat the victim. The device is a sufficiently small and lightweight unit to permit being carried by an individual.

1 . A device capable of detecting a chemical or biological agent, the device comprising:
 a freestanding tube portion comprising an internal passage containing a substance selective to a chemical or biological agent so that matter accumulates within the freestanding tube portion;   means for flowing a fluidic sample through the freestanding tube portion;   means for vibrating the freestanding tube portion at a resonant frequency thereof that varies with a combined density of the freestanding tube portion and contents of the internal passage;   means for sensing movement of the freestanding tube portion and producing an output signal based on the resonant frequency of the freestanding tube portion, the output signal being indicative of accumulation of the matter; and   means for identifying the agent in the fluidic sample based on the accumulation of the matter in the freestanding tube portion.   
     
     
         2 . The device according to  claim 1 , wherein the freestanding tube portion is a constituent of a unit sufficiently small and light-weight to be carried by a person. 
     
     
         3 . The device according to  claim 2 , wherein the unit comprises at least one antidote, means coupled to the at least one antidote for selecting the at least one antidote based on the agent identified by the identifying means, and means for delivering the at least one antidote into the body of the person. 
     
     
         4 . The device according to  claim 3 , wherein the delivering means comprises:
 a second freestanding tube portion through which the at least one antidote flows;   means for vibrating the second freestanding tube portion at a resonant frequency thereof that varies with the density of the fluid flowing therethrough, the Coriolis effect causing the second freestanding tube portion to twist while being vibrated at resonance, the second freestanding tube portion exhibiting a degree of twist that varies with the mass flow rate of the fluid flowing therethrough;   means for sensing movement of the second freestanding tube portion and producing a first output signal based on the resonant frequency of second the freestanding tube portion and a second output signal based on the degree of twist of the second freestanding tube portion;   means for measuring elapsed time during which the fluid has flowed through the second freestanding tube portion; and   means for stopping flow of the fluid through the second freestanding tube portion in response to a specified amount of the at least one antidote having passed through the second freestanding tube portion based on the elapsed time and the second output signal.   
     
     
         5 . The device according to  claim 3 , wherein the unit comprises a plurality of antidotes and the selecting means selects among the plurality of antidotes. 
     
     
         6 . The device according to  claim 5 , wherein the selecting means is operable to select more than one antidote, and the delivering means is operable to deliver the more than one antidote into the body of the person. 
     
     
         7 . The device according to  claim 3 , wherein the delivering means operates to deliver the at least one antidote subdermally, intravenously, intra-arterially, subcutaneously, intramuscularly, intraperitoneally or intrathecally. 
     
     
         8 . The device according to  claim 1 , wherein the fluidic sample flowed by the flowing means through the freestanding tube portion is air, water, blood or urine. 
     
     
         9 . The device according to  claim 1 , wherein the freestanding tube portion, the vibrating means and the sensing means are contained within an evacuated, hermetically-sealed enclosure. 
     
     
         10 . The device according to  claim 1 , wherein the freestanding tube portion is a micromachine. 
     
     
         11 . A method of detecting a chemical or biological agent, the method comprising the steps of:
 flowing a fluidic sample through an internal passage within a freestanding tube portion, the passage containing a substance selective to a chemical or biological agent so that matter accumulates within the freestanding tube portion;   vibrating the freestanding tube portion at a resonant frequency thereof that varies with a combined density of the freestanding tube portion and contents of the internal passage;   sensing movement of the freestanding tube portion and producing an output signal based on the resonant frequency of the freestanding tube portion, the output signal being indicative of accumulation of the matter; and   identifying the agent in the fluidic sample based on the accumulation of the matter in the freestanding tube portion.   
     
     
         12 . The method according to  claim 11 , wherein the freestanding tube portion is a constituent of a unit carried by a person. 
     
     
         13 . The method according to  claim 12 , wherein the unit comprises at least one antidote, means coupled to the at least one antidote for selecting the at least one antidote, and means for delivering the at least one antidote into the body of the person, and wherein the method further comprises the steps of:
 sending a signal to the selecting means based on the agent identified in the fluidic sample;   selecting with the selecting means the at least one antidote as being capable of counteracting the agent; and then delivering with the delivering means the at least one antidote into the body of the person.   
     
     
         14 . The method according to  claim 13 , wherein the step of delivering the at least one antidote comprises the steps of:
 flowing the at least one antidote through a second freestanding tube portion;   vibrating the second freestanding tube portion at a resonant frequency thereof that varies with the density of the fluid flowing therethrough, the Coriolis effect causing the second freestanding tube portion to twist while being vibrated at resonance, the second freestanding tube portion exhibiting a degree of twist that varies with the mass flow rate of the fluid flowing therethrough;   sensing movement of the second freestanding tube portion and producing a first output signal based on the resonant frequency of second the freestanding tube portion and a second output signal based on the degree of twist of the second freestanding tube portion;   measuring elapsed time during which the fluid has flowed through the second freestanding tube portion; and   stopping flow of the fluid through the second freestanding tube portion in response to a specified amount of the at least one antidote having passed through the second freestanding tube portion based on the elapsed time and the second output signal.   
     
     
         15 . The method according to  claim 13 , wherein the unit comprises a plurality of antidotes and the selecting means selects among the plurality of antidotes. 
     
     
         16 . The method according to  claim 15 , wherein the selecting step comprises selecting more than one antidote, and the delivering step comprises delivering the more than one antidote into the body of the person. 
     
     
         17 . The method according to  claim 13 , wherein the at least one antidote is delivered subdermally, intravenously, intra-arterially, subcutaneously, intramuscularly, intraperitoneally or intrathecally. 
     
     
         18 . The method according to  claim 11 , wherein the fluidic sample is air, water, blood or urine. 
     
     
         19 . The method according to  claim 11 , wherein the freestanding tube portion is contained within an evacuated, hermetically-sealed enclosure, and the vibrating and sensing steps are performed by vibrating and sensing means contained within the enclosure. 
     
     
         20 . The method according to  claim 11 , further comprising the step of fabricating the freestanding tube portion using a micromachining process.