Limits...
Design of a New Type of Compact Chemical Heater for Isothermal Nucleic Acid Amplification.

Shah KG, Guelig D, Diesburg S, Buser J, Burton R, LaBarre P, Richards-Kortum R, Weigl B - PLoS ONE (2015)

Bottom Line: Previous chemical heater designs for isothermal nucleic acid amplification have been based on solid-liquid phase transition, but using this approach, developers have identified design challenges en route to developing a low-cost, disposable device.Here, we demonstrate the feasibility of a new heater configuration suitable for isothermal amplification in which one reactant of an exothermic reaction is a liquid-gas phase-change material, thereby eliminating the need for a separate phase-change compartment.This design offers potentially enhanced performance and energy density compared to other chemical and electric heaters.

View Article: PubMed Central - PubMed

Affiliation: Department of Bioengineering, Rice University, Houston, Texas, United States of America; PATH, Seattle, Washington, United States of America.

ABSTRACT
Previous chemical heater designs for isothermal nucleic acid amplification have been based on solid-liquid phase transition, but using this approach, developers have identified design challenges en route to developing a low-cost, disposable device. Here, we demonstrate the feasibility of a new heater configuration suitable for isothermal amplification in which one reactant of an exothermic reaction is a liquid-gas phase-change material, thereby eliminating the need for a separate phase-change compartment. This design offers potentially enhanced performance and energy density compared to other chemical and electric heaters.

No MeSH data available.


Related in: MedlinePlus

Device design.(a) Labeled vertical cross-section and (b) photograph of used, proof-of-concept, direct liquid-vapor phase change, and isothermal chemical heater. The exothermic reaction occurs in a standard laboratory 5 mL tube and is initiated by the addition of methanol to the tube.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4591995&req=5

pone.0139449.g001: Device design.(a) Labeled vertical cross-section and (b) photograph of used, proof-of-concept, direct liquid-vapor phase change, and isothermal chemical heater. The exothermic reaction occurs in a standard laboratory 5 mL tube and is initiated by the addition of methanol to the tube.

Mentions: In light of these design specifications, six identical proof-of-concept prototypes were constructed as shown in Fig 1 by drilling a 9/16” diameter, 60 mm hole in a 28.5 mm x 28.5 mm x 70 mm reusable PVC foam block (Item 85925K352, McMaster-Carr). A standard 5 mL centrifuge tube (Eppendorf North America Biotools) was pressed into the cavity and used as a disposable reaction chamber, and a pressure-equalizing hole was drilled into the cap with a 0.067” diameter drill bit. A 20 mm x 32 mm fuel pack was constructed by heat-sealing muslin (Item 10011, Muslinbag) that contained 400–450 μm particle diameter, 500 ± 2 mg, mechanically alloyed magnesium-iron (Luxfer Magtech Inc, USA) and 0, 10, 25, 50, 75 or 100 ± 2 mg sodium chloride (Item S7653, Sigma-Aldrich). In a second set of experiments, with 50 mg of sodium chloride mixed into the fuel pack, 0, 10, 20, 30, 40, 50 or 60 ± 2 mg anhydrous copper (II) chloride (Item 22011, Sigma-Aldrich) was added to the reaction chamber to prevent premature corrosion (50 mg of copper (II) chloride is needed to bring the system to boiling). An open-cell annular foam PCR tube holder was placed at an angle at a fixed height in the centrifuge tube to ensure that a 100 μL PCR tube was consistently positioned in all tests.


Design of a New Type of Compact Chemical Heater for Isothermal Nucleic Acid Amplification.

Shah KG, Guelig D, Diesburg S, Buser J, Burton R, LaBarre P, Richards-Kortum R, Weigl B - PLoS ONE (2015)

Device design.(a) Labeled vertical cross-section and (b) photograph of used, proof-of-concept, direct liquid-vapor phase change, and isothermal chemical heater. The exothermic reaction occurs in a standard laboratory 5 mL tube and is initiated by the addition of methanol to the tube.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4591995&req=5

pone.0139449.g001: Device design.(a) Labeled vertical cross-section and (b) photograph of used, proof-of-concept, direct liquid-vapor phase change, and isothermal chemical heater. The exothermic reaction occurs in a standard laboratory 5 mL tube and is initiated by the addition of methanol to the tube.
Mentions: In light of these design specifications, six identical proof-of-concept prototypes were constructed as shown in Fig 1 by drilling a 9/16” diameter, 60 mm hole in a 28.5 mm x 28.5 mm x 70 mm reusable PVC foam block (Item 85925K352, McMaster-Carr). A standard 5 mL centrifuge tube (Eppendorf North America Biotools) was pressed into the cavity and used as a disposable reaction chamber, and a pressure-equalizing hole was drilled into the cap with a 0.067” diameter drill bit. A 20 mm x 32 mm fuel pack was constructed by heat-sealing muslin (Item 10011, Muslinbag) that contained 400–450 μm particle diameter, 500 ± 2 mg, mechanically alloyed magnesium-iron (Luxfer Magtech Inc, USA) and 0, 10, 25, 50, 75 or 100 ± 2 mg sodium chloride (Item S7653, Sigma-Aldrich). In a second set of experiments, with 50 mg of sodium chloride mixed into the fuel pack, 0, 10, 20, 30, 40, 50 or 60 ± 2 mg anhydrous copper (II) chloride (Item 22011, Sigma-Aldrich) was added to the reaction chamber to prevent premature corrosion (50 mg of copper (II) chloride is needed to bring the system to boiling). An open-cell annular foam PCR tube holder was placed at an angle at a fixed height in the centrifuge tube to ensure that a 100 μL PCR tube was consistently positioned in all tests.

Bottom Line: Previous chemical heater designs for isothermal nucleic acid amplification have been based on solid-liquid phase transition, but using this approach, developers have identified design challenges en route to developing a low-cost, disposable device.Here, we demonstrate the feasibility of a new heater configuration suitable for isothermal amplification in which one reactant of an exothermic reaction is a liquid-gas phase-change material, thereby eliminating the need for a separate phase-change compartment.This design offers potentially enhanced performance and energy density compared to other chemical and electric heaters.

View Article: PubMed Central - PubMed

Affiliation: Department of Bioengineering, Rice University, Houston, Texas, United States of America; PATH, Seattle, Washington, United States of America.

ABSTRACT
Previous chemical heater designs for isothermal nucleic acid amplification have been based on solid-liquid phase transition, but using this approach, developers have identified design challenges en route to developing a low-cost, disposable device. Here, we demonstrate the feasibility of a new heater configuration suitable for isothermal amplification in which one reactant of an exothermic reaction is a liquid-gas phase-change material, thereby eliminating the need for a separate phase-change compartment. This design offers potentially enhanced performance and energy density compared to other chemical and electric heaters.

No MeSH data available.


Related in: MedlinePlus