Team:ZJUT-China/Experiments/special experiment

Special experiments

Test for the resistance of formaldehyde

Materials

Different concentration of formaldehyde solution

Overnight target cell culture

ELIASA

Protocols

1. Inoculate 50ml of LB medium with 1ml of the preculture in several tubes and grow at 37°C to an OD600nm of 0.6 shaking the culture at 200rpm.

2. Add different proportions of water and formaldehyde to the same volume and add to the culture to get certain concentration of formaldehyde solution

3. Add IPTG if the gene is on pet28b plasimid.

4. Incubate for 6 hours and use ELIASA to measure OD.

Safety considerations

✔ Dilute the formaldehyde in the fuming cupboard before use it.

✔ Wearing laboratory coat, gloves is necessary to follow this procedure.

✔ All the manipulations of bacteria are carried out in a laminar flow cabinet.

✔ Work sufaces should be decontaminated with 70% alcohol.

✔ All materials that have been in touch with cells will be autoclaved.

Acetylacetone method in determining

formaldehyde

Materials

Detection equipment: enzyme marker reagent.

Acetylacetone solution: draw 3.0ml acetylacetone (AR) water and dilute it to 200ml.

Acetic acid-ammonium acetate buffer solution: weigh 15.42g ammonium acetate (AR) dissolved in 300ml water, add 2.3ml glacial acetic acid, adjust PH value to nearly 5.75, dilute with water to 400ml.

Protocols

Making of Standard Curve.

1. 0.00,0.20,0.40,0.60 and 0.80ml formaldehyde standard solution (equivalent to formaldehyde content: 0.00,2.0,4.0, 6.0, 8.0ug formaldehyde) were absorbed into 10ml colorimetric tube, respectively.

2. Add 2ml acetic acid-ammonium acetate buffer solution and 1ml acetylacetone solution, add water to scale, mix well, place in 70 􏰃 water bath for 30 min, remove and cool to room temperature.

3. Add the sample to 96 well-plate in turn, use ELIASA to measure absorbance by OD413.

4. Taking the absorbance and the content of formaldehyde as the longitudinal and transverse coordinates, draw the standard curve.