Method and apparatus for determination of chemical species in body fluid

A concentration patch for concentrating components of a body fluid under the influence of body heat, comprising:

• a concentration zone adapted for communication with a source of body fluid;
• a discharge zone exposed too the atmosphere;
• a hydrophobic membrane, separating the concentration zone from the discharge zone;
• and
• means on the patch for removably securing the concentration zone in communication with the source of body fluid,
• wherein volatile components of the body fluid accumulated in the concentration zone are driven through the hydrophobic membrane in the vapor phase, but not in the liquid phase, thereby concentrating non-volatile desired components in the concentration zone.

A dermal concentration patch for concentrating components of perspiration expressed through the skin under the influence of body heat, comprising:

• a concentration zone adapted to be disposed in fluid communication with the skin, said zone being formed of a material which accumulates said perspiration;
• and
• a hydrophobic membrane adjacent the concentration zone, said membrane adapted to retain volatile and non-volatile components of said perspiration in the fluid phase within the concentration zone but permitting passage of volatile components of said perspiration in the vapor phase,
• wherein said concentration patch has sufficient permeability so as to permit water to escape through said concentration zone and hydrophobic membrane and outside of the concentration patch.

A dermal concentration patch for concentrating components of a body fluid under the influence of body heat, consisting essentially of:

• a hydrophilic concentration zone adapted for communication with a source of said body fluid;
• a hydrophobic membrane adjacent said concentration zone, said membrane adapted to concentrate non-volatile components of said body fluid in said concentration zone by permitting passage of volatile components therethrough in the vapor phase whilst retaining non-volatile and volatile components in the concentration zone in the fluid phase;
• and
• means on the patch for removably securing the concentration zone in communication with the source of body fluid.

A method for determining the presence of an analyte in a body fluid, comprising the steps of:

• accumulating a quantity of a body fluid from a subject mammal in a concentration patch;
• removing from the concentration patch a substantial portion of the water component from the fluid under the influence of body heat too form a concentrate;
• and
• binding at least one analyte in the concentrate to an immobilized specific binding pattern of that analyte.

A dermal concentration patch for the noninvasive determination of at least one preselected low-concentration analyte in a body fluid expressed through the skin as perspiration without the need for conventional instrumentation, comprising:

• a first layer adapted to be disposed in fluid communication with the skin, said layer being formed of a material which accumulates the body perspiration which vaporizes under the influence of body heat which is readily conducted from the surface of the skin through the accumulated perspiration fluids;
• a second layer adjacent the first layer, the second layer being formed of a material which will permit the passage of the vapor phase of fluids expressed from the skin but retain the fluid phase thereof within said first layer;
• and
• an immobilized reagent in contact with the first layer and with the accumulated perspiration for selectively binding with at least one preselected analyte,
• said concentration patch having sufficient permeability so as to permit water to escape through said first and second layers and outside of the concentration patch.

A dermal concentration patch for the noninvasive determination of at least one preselected low-concentration analyte in a body fluid expressed through the skin as perspiration without the need for conventional instrumentation, comprising:

• a first layer adapted to be disposed in fluid communication with the skin, said layer being formed of a material which accumulates the body perspiration which is lost under the influence of body heat;
• a second layer adjacent the first layer, the second layer formed of a material which will permit passage of the liquid expressed from the skin;
• and
• an immobilized reagent in the second layer which selectively binds at least one preselected analyte,
• said concentration patch having sufficient permeability so as to permit water to escape through said first and second layers and outside of the concentration patch.

A dermal concentration patch for determining the presence of an analyte in a subject mammal's perspiration, consisting essentially of:

• a water permeable support layer having a first and a second side;
• at least one specific binding partner for the analyte to be determined immobilized to the support layer;
• and
• means for removably securing the first side of the support layer in fluid communication with the subject's skin without preventing water from escaping through the support layer and outside of the concentration patch.

A method for determining the presence of an analyte in a body fluid from a subject mammal, comprising the steps of:

• removably securing a concentration zone in fluid communication with a source of said body fluid;
• accumulating a quantity of said body fluid from said subject mammal in said concentration zone;
• and
• concentrating non-volatile components of said body fluid in said concentration zone by permitting passage of volatile components through a hydrophobic membrane in the vapor phase whilst retaining non-volatile and volatile components in the concentration zone in the fluid phase underneath said hydrophobic membrane.