Devices for performing colorimetric assay with plucked human hair
Apparatuses are disclosed for performing calorimetric assays with plucked human hair using a device adapted for that purpose. This device may include a transparent reaction vessel connected via a capillary tube to a burst pack, and connected via another capillary tube to a funnel, into which a plucked human hair may be placed.
1. A device for performing a colorimetric assay comprising:
an encasement;
a cavity within the encasement comprising a burst pack comprising a first reagent, the burst pack situated such that it may be burst by pressure from one or more human fingers, wherein the first reagent reacts with the follicle of a human hair to produce a change in a measurable optical property of the reagent;
a transparent reaction vessel within the encasement comprising a reaction chamber;
a first capillary tube opening on one end to the reaction chamber, and opening on another end to a funnel, said funnel opening to the atmosphere external to the reaction vessel; and
a second capillary tube providing a fluid connection between the cavity and the reaction chamber.
2. The device of claim 1 , wherein at least a portion of the reaction chamber is coated with a second reagent.
3. The device of claim 2 , wherein the second reagent is an antibody.
4. The device of claim 1 , further comprising a plucked human hair that has been inserted through the funnel, such that a hair follicle of the plucked human hair is situated within the reaction chamber.
5. The device of claim 1 , wherein the first capillary tube has a diameter between about 0.25 mm and about 2.5 mm.
6. The device of claim 1 , wherein the first reagent is an aqueous solution comprising:
about 3 to about 7 mM p-nitrophenyl sulfate; and
about 0.07 to about 0.13 mM minoxidil; and
about 15 to about 25 μM adenosine 3′,5′-diphosphate (PAP) or adenosine 3′-phosphate,5′-phosphosulfate (PAPS).
7. The device of claim 6 , wherein the concentration of adenosine 3′,5′-diphosphate (PAP) or adenosine 3′-phosphate,5′-phosphosulfate (PAPS) is about 20 μM; the concentration of p-nitrophenyl sulfate is about 5 mM; and the concentration of minoxidil is about 0.1 mM.
8. The device of claim 6 , wherein the first reagent further comprises:
about 30 to about 70 mM sodium or potassium phosphate buffer (pH about 6.5 to about 8.0); and
about 3 to about 7 mM magnesium chloride.
9. A system for performing a colorimetric assay, comprising:
the device of claim 1 ;
a spectrophotometer comprising a sample port shaped to accommodate said device, wherein the light source is oriented to pass light through the transparent reaction vessel.
10. A method for performing a colorimetric assay using the device of claim 1 , comprising:
obtaining a sample from a human subject, comprising a hair that has been plucked from the human subject, the hair comprising a follicle at one end;
placing the hair, follicle-end first, into the funnel of the device, and situating the follicle such that it is within the reaction chamber;
breaking the burst pack; and
measuring a color change of material in the reaction vessel.
11. The method of claim 10 , wherein the calorimetric assay is to measure minoxidil sulfotransferase activity in the sample, further comprising:
generating an activity value indicative of the minoxidil sulfotransferase activity level in the sample, wherein the activity value correlates with the color change;
comparing the activity value to one or more standardized activity values, each standardized activity value representing either high or low expected minoxidil response for hair re-growth or retention for a class of patients including the subject, thereby producing an indication of either high or low expected minoxidil response for hair re-growth or retention for the subject at a particular dosage of minoxidil; and
presenting the indication to the human subject.
12. The method of claim 10 , wherein the step of measuring comprises:
taking a digital photograph of the reaction vessel;
running an application on a computer device which compares a color value obtained from the digital photograph in a visual area of the digital photograph corresponding to the reaction vessel with a standard color value.
13. A device for performing a colorimetric assay comprising:
an encasement;
a reaction vessel within the encasement comprising a reaction chamber;
a first capillary tube opening on one end to the reaction chamber, and opening on another end to a funnel, said funnel opening to the atmosphere external to the reaction vessel, wherein the first capillary tube has a diameter between about 0.25 ml and about 2.5 ml;
a first reagent which reacts with the follicle of a human hair to produce a change in a measurable property of the reagent.
14. The device of claim 13 , further comprising:
a cavity within the encasement comprising a burst pack comprising the first reagent, the burst pack situated such that it may be burst by pressure from one or more human fingers; and
a second capillary tube providing a fluid connection between the cavity and the reaction chamber.
15. The device of claim 14 , further comprising a button which bursts the burst pack when pressed.
16. The device of claim 13 , further comprising:
an electrical current source;
a switch;
a visual display connected to the electrical current source when the switch is activated, and configured to provide a visual indication when a reaction between a human hair inserted into the reaction chamber hair and the first reagent has begun.
17. The device of claim 16 , further comprising an electronic timer connected to the electrical current source when the switch is activated, and configured to provide a visual indication on the display when a predefined period of time has elapsed.
18. The device of claim 13 , wherein a portion of the reaction vessel is coated with an indicator material arranged in the shape of a human-readable visual indicator, wherein the indicator material is activated to provide a visual indication by said change in the measurable property of the reagent.
19. A method for performing a colorimetric assay using the device of claim 13 , comprising:
obtaining a sample from a human subject, comprising a hair that has been plucked from the human subject, the hair comprising a follicle at one end;
placing the hair, follicle-end first, into the funnel of the device, and situating the follicle such that it is within the reaction chamber;
reacting the follicle with the first reagent for a predetermined period of time; and
measuring said measurable property of the reagent.