What is the standard procedure for preparing atractyloin reference solution?

How many milliliters do you have, I have 25 milliliters. Put the volumetric flask into the balance, directly put the top cover of the weighing paper roll into the mouth of the volumetric flask, use a small spoon to hold the medicine in it, and finally gently knock the right hand with the left hand to let the medicine in.

Frequently asked questions about standard solution configurations.

1 Can the solvent be added directly to the standard bottle to dissolve and then transferred to a volumetric flask for volumetric volume?

No. Unless otherwise specified, the quality and volume of the product given by all standard manufacturers are not exact values, for example, the weight of the product in the bottle of a 10 mg standard may be greater than 10 mg, such as or 11 mg. If the weight of the product is an exact value, the manufacturer will generally indicate it.

2 Solvent Selection:

Select the appropriate solvent according to the existing method or the relevant physical and chemical properties of the substance. Inappropriate solvents may cause insolvency or product degradation.

3 Weighing Method:

Choose the right balance based on the weight you need to weigh and the tolerance. If a 1/100,000 balance is used, it is recommended that the weighing value should not be less than 10mg. When purchasing a product, please also pay attention to whether the weight of the product can meet your needs.

Generally, the incremental or subtractive method is used for weighing, and here are some suggestions for your reference:

aBefore weighing: It is recommended to place frozen or refrigerated products at room temperature first, and place the products upright for a period of time, so that all the products are concentrated at the bottom for easy access. In particular, viscous substances can be tilted to 45 degrees in the vertical direction to concentrate the product on the edge of the bottom of the bottle. If you are concerned about sticking to the cap, you can shake the bottle before opening the cap to concentrate the product to the bottom.

b Powder or crystals:

It is recommended to use the incremental method of weighing, prepare a suitable drying container, and pour the product into the container after zeroing, and obtain the weight of the substance in the container for the preparation of the standard solution.

cViscous or liquid:

It is recommended to use the subtractive method to weigh the weight of the original product with the bottle, and then use appropriate equipment to remove the required sample into the preparation container, and weigh the weight of the removed product with the bottle, the difference is the weight of the actual standard solution used.

d. If there is a substance sticking to the bottle cap, you can weigh it together with the bottle cap when weighing by the reduction method, and pay attention to using dry utensils when pipetting the product.

4 Solution Preparation:

When the standard and solvent are exothermic or endothermic during the preparation process, the volume of the standard solution will be abnormal, and the concentration of the prepared solution will be incorrect.

5Can the volumetric flask dissolve solids when preparing standard solutions?

No. Solid standards should be weighed and dissolved in a suitable beaker before being drained into a volumetric flask via a glass rod.

6 Can the volume store the prepared standard solution?

No. The volumetric flask is a measuring device, not a container, and a suitable reagent bottle should be selected to store the prepared standard solution.

The line of several dots made out of the standard (which is what you call the reference solution) is called the standard curve.

The standard generally selects 5 most suitable concentrations from small to large: A1, A2, A3, A4, and A5

The use of standard curves is conditional: one of the most important conditions is that the concentration of the unknown sample must be between A1 and A5.

If the concentration of the unknown sample is lower than A1 or beyond A5, the standard curve will be invalid (because everything is based on the experimental results, you did not do experiments smaller than A1 and greater than A5, so you cannot extend the standard curve to both sides).

If it is below A1 Solution: Concentrate the unknown sample to increase its concentration to A1 "If the unknown sample is greater than A5 Solution: Contrary to the above, dilute the unknown sample or set several concentrations greater than A5 while removing several smaller standard points.

Because if the difference between the two concentrations is too large, the absolute peak area of the component will change greatly, which will cause the component peak area ratio to change, which will lead to an increase in the error of the analysis results! :d

If the concentration difference is too large, the linear relationship will be worse.

It's stupid, you can match it how you want!

If the compound is a drug, it is specified in the pharmacopoeia, and the specific configuration method can be consulted in the pharmacopoeia.