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Third-party testing laboratory instruments have requirements for sending samples, do you know?

Release date: 2016-07-26

核磁共振波谱仪: 1. Nuclear magnetic resonance spectrometer:

(1) The purity of the submitted samples should generally be> 95%, and no impurities such as iron filings, dust, filter paper hair, etc. The amount of samples required for general organics: 1H spectrum> 5mg, 13C spectrum> 15mg, the sample size required for the polymer should be appropriately increased.

(2) This instrument configuration can only analyze liquid samples. It is required that the samples have good dissolving properties in a certain deuterated solvent. The sender should choose the solvent used first. The deuterated solvents in this room are chloroform, heavy water, methanol, acetone, DMSO, benzene, o-dichlorobenzene, acetonitrile, pyridine, acetic acid, and trifluoroacetic acid.

(3) Samplers are requested to provide possible structures or sources of samples as much as possible. If there are special requirements (such as detection temperature, spectral width, etc.), please explain.

2. Infrared spectrometer:

In order to protect the instrument and ensure the quality of the infrared spectrum of the sample, the sample sent by this instrument must be:

(1) The sample must be purified in advance to ensure sufficient purity;

(2) The sample must be dewatered and dried in advance to avoid damaging the instrument and at the same time avoid interference of water peaks on the sample spectrum;

(3) For samples that are prone to deliquescent, please prepare your own dryer;

(4) For samples that are volatile, sublimable, and unstable to heat, please use a container with a sealed lid or stopper and tightly seal it, and it must be indicated on the sample analysis task list;

(5) For toxic and corrosive samples, users must pack them in sealed containers. Samples must be clearly marked on the vial label and on the analysis task list when sending samples.

3. Organic mass spectrometer:

Suitable for analysis of liquid and solid organic compound samples with a relative molecular mass of 50 ~ 2000u. The sample should be as pure as possible as a single component.

4. Gas chromatography-mass spectrometry:

Gas chromatographs use capillary columns (packed columns cannot be used).

The sample that enters the gas chromatography furnace must be completely vaporized within the operating temperature range of the column.

5. Liquid chromatography-mass spectrometry:

(1) Flammable, explosive, poisonous and corrosive samples must be specified.

(2) In order to ensure accurate and reliable analysis results, the sample is required to be completely dissolved without mechanical impurities; for samples that have not been formulated with a solution, please indicate the solvent, and for samples that have been formulated with a solution, please indicate the concentration.

(3) Please provide the structural formula, molecular weight or functional groups of the sample as much as possible in order to select the ionization method; if there are special requirements, please provide specific experimental conditions.

(4) When liquid chromatography-mass spectrometry is used, all buffer systems are prepared with volatile buffers such as acetic acid, ammonium acetate, and tetrabutylammonium hydroxide. For those who require quantitative analysis, please provide standard reference materials.

6. Time-of-flight mass spectrometer:

(1) the type, composition and sample amount of the sample

This instrument is good at measuring peptides and proteins, and can also measure other biological macromolecules such as polysaccharides, nucleic acids and high molecular polymers, synthetic oligomers, and some organic compounds with relatively low molecular weight, such as C60 or C60 grafts. The test sample can be a single component or multiple components, but the more sample components, the more complicated the spectrum, and the more difficult the analysis of the spectrum is; if there is mutual inhibition between the components during the ionization process , It is not necessarily guaranteed that each component will show a peak. The sample size for routine measurement is about 1-10 picomoles / microliter.

(2) Solubility of the sample

The sample to be tested must be soluble in a suitable solvent, preferably an undissolved solid or pure liquid. If the sample is a solution, provide information such as the solvent, concentration, or content of the sample.

(3) Purity

To obtain high-quality mass spectra, peptide and protein samples should be free of sodium chloride, calcium chloride, potassium hydrogen phosphate, trinitrotoluene, dimethyl sulfoxide, urea, glycerol, Tween, sodium dodecyl sulfate Wait. If the test sample cannot avoid using the above reagents during the pretreatment process, the sample must be purified by dialysis and high performance liquid chromatography. Water, ammonium bicarbonate, ammonium acetate, ammonium formate, acetonitrile, trifluoroacetic acid, etc. are all suitable reagents for purifying samples. After purification of protein samples, they should be lyophilized as much as possible. Salts in samples can be eliminated by ion exchange.

7. UV-visible absorption spectrometer:

(1) The concentration of the sample solution must be appropriate, and it must be clear and transparent, and there must be no air bubbles or suspended matter;

(2) The amount of solid sample is> 0.2g, and the amount of liquid sample is> 2 ml.

8. Gas chromatograph:

Samples that can be directly analyzed should be volatile and thermally stable. Generally, the boiling point does not exceed 300 ℃, and samples that cannot be directly injected need to be pretreated.

9. Liquid chromatograph:

The sample should be dry, and it is best to provide the structure of the component to be tested; for complex samples, as much as possible what other components may be in the sample.

10. Elemental analyzer:

(1) Fill in the element analysis sample registration form, and provide as much as possible the theoretical content of the molecular formula and elements or other relevant information;

(2) The sample must be homogeneous solid particles or liquid without adsorbed water and purified. If the sample is impure (containing adsorbed water, organic solvents, inorganic salts or other impurities), it will affect the analysis results and make the test value inconsistent with the calculated value;

(3) The sample should be of sufficient quantity to meet the linearity and sensitivity of the method and instrument.

11. Ion chromatograph:

The submitted samples can be dissolved in water, or dilute acids and bases. The acid and base used must not contain the ions to be tested. For compounds that contain the element to be measured in the sample, but exist in a non-ionic state in water, acid, and alkali solutions, corresponding sample pretreatment is required.

12. Plasma atomic emission spectrometer:

(1) Requirements for samples submitted for inspection (testing conditions):

① Please inform the sample of the source, type and property (such as ore, alloy, silicate, special solid solution, polymer, etc.).

List the main components, impurity components and their (estimated) content as much as possible; what is the lowest (estimated) content of the elements to be tested? For solutions, please specify the media components (the types of solvents, acids and bases, and their (estimated) content) Does it contain fluorine (F-) or not? Because fluorine (F-) will seriously corrode the atomizer!

② The solid sample should be made into a solution without any organic matter, and its final acidity should be controlled to 1 mol, and the sample volume: 5-50 ml.

If it contains suspended matter or precipitation, it must be filtered; please also send the reagent blank solution at the same time for deduction of blank, this item is free of charge!

③ The sample is required to be processed into a solution before being sent to the test center.

(2) Due to limited conditions, this laboratory cannot analyze the following elements and certain substances:

① Samples that are volatile and lose when heating and dissolving with acid (such as B, Hg, S-2, Se, and Si when dissolving samples with hydrofluoric acid (HF));

②Ceramics, glass and other inorganic acids cannot be dissolved, and only alkali melting can be used;

③ Organic silicon, silicone rubber, plastic products, fibers or any ashing within 500 oC, and subsequent acid digestion:

A. Volatile losers;

B. Can not be ashed or insoluble (such as B, Bi, Ge, Hg, Os, Ru, Sb, Se, Sn, Tl and Si when dissolved with hydrofluoric acid (HF); special solid solution, high Polymer, etc.)

13. Atomic fluorescence spectrometer:

(1) General requirements for sample analysis

The object of atomic fluorescence spectrometer analysis is arsenic (As), selenium (Se), germanium (Ge), tellurium (Te), and mercury (Hg) atoms in ionic state. The sample must be aqueous solution or soluble in acid.

(2) Solid samples

① Inorganic solid sample The sample should maintain proper acidity after simple dissolution.

Detection of arsenic (As), selenium (Se), tellurium (Te), mercury (Hg), the medium is hydrochloric acid (5%, v / v);

Detection of germanium (Ge), the medium is sulfuric acid (5%, v / v);

For the detection of mercury (Hg), the medium can also be nitric acid (5%, v / v), and the detection (As) medium can also be sulfuric acid (2%, v / v).

Because copper, silver, gold, platinum and other metals have a greater interference with the elements to be measured, arsenic, selenium, tellurium, and mercury in these types of alloy samples should not be measured by this instrument.

② Organic or biological solid samples

The sample was nitrified into a solution and maintained at an appropriate acidity. The medium acidity was the same as that of the inorganic sample.

(3) Limits of the elements to be tested in the sample

Determined by the sensitivity of the instrument and the analysis method, the upper and lower limits of the sample containing the element to be measured are 0.05 μg / g ~ 500 μg / g. If the sample does not fall within this content range, testing with this instrument will not guarantee the accuracy and reliability of the test results.

(4) sample size

For each element tested, the amount of solid sample is not less than 2 g, the amount of liquid sample is not less than 20 mL, and the amount of water sample is not less than 100 mL.

(5) Other

Please consult the relevant literature before submitting samples, and try to provide relevant information.

14. Differential scanning calorimeter:

The solid sample does not decompose or sublimate in the temperature range detected, and no volatile matter is generated. Sample size: single detection of not less than 20mg of inorganic or organic materials, no less than 5mg of drugs. Please indicate the test conditions (including test temperature range, rate of rise and fall, constant temperature time, etc.) when sending samples.

15. Thermogravimetric Analyzer:

Sample volume: not less than 30mg. When submitting the sample, please indicate the detection temperature range, the experimental atmosphere (air, N2 or Ar), the heating rate, and the gas flow rate (if there are special requirements).

16. X-ray powder diffractometer:

The samples submitted for inspection can be powder, block, film and other shapes. The powder sample needs about 0.2g (depending on its density and diffraction ability); the block sample requires an approximate plane with an area less than 45px x 45px; the film sample requires a certain thickness and the area is less than 45px x 45px; other samples Consulting laboratory.

17. X-ray single crystal diffractometer:

The sample submitted for inspection must be single crystal. When selecting a crystal, pay attention to the surface finish, color and transparency of the selected crystal. No small crystals are attached, no defects such as overlapping of defects, cleavage damage, cracks, etc. The length, width, and height of the crystal are 0.1 to 0.4 mm, that is, the diagonal length of the crystal does not exceed 0.5 mm (large crystals can be sampled by cutting methods, and small crystals need to consider their diffractive power).

18. Transmission electron microscope:

Due to the high voltage limitation of the electron microscope, the transmitted electron beam generally can only penetrate thin samples with thicknesses below tens of nanometers. Except for fine-grained samples, which can be directly sampled by the medium dispersion method, other methods of sample preparation include physical thinning (ion and dual-spray thinning) and ultra-thin sectioning. In general, the sample preparation process that requires physical thinning must be completed by the user (departments that do not have the conditions for sample preparation can rent related equipment in this room). The preparation of ultra-thin section samples requires complex procedures such as sample pretreatment, embedding, and sectioning, and the cycle is relatively long (about one week).

Because the instrument is a high-resolution electron microscope, in order to ensure the performance of the instrument and to display its high-resolution image observation characteristics, samples are currently mainly accepted in the field of materials.

19. Field emission scanning electron microscope:

The samples submitted for inspection must be dry solid, lumpy, flake, fibrous and powder. It should have certain chemical and physical stability, and it will not volatilize or deform under vacuum and electron beam bombardment; non-magnetic, radioactive and corrosive. Sample preparation of biological soft tissues with high water content requires the user to perform the fixation, cleaning, dehydration, and replacement with (iso) amyl acetate before the critical point drying, and then the critical point drying is performed by the laboratory. Observe the image sample should be sprayed with gold film in advance. Generally, the sample should be as small as possible (≤10x10x5mm is more convenient). Each powder sample requires about 1 gram. Nanometer samples generally need to be dispersed by ultrasound and sprayed with ultra-fine gold film.

20. Scanning electron microscope-X-ray spectrometer:

The submitted samples must be dry solids, which can be lumpy, flake, fibrous, granular or powdery. It should have certain chemical and physical stability, and it will not volatilize or deform under vacuum and electron beam bombardment; non-magnetic, radioactive and corrosive. For biological soft tissue samples with high moisture content, users are required to perform fixation, cleaning, dehydration, and replacement with (iso) pentyl acetate before critical point drying. Finally, a critical point drying process is performed by the room. The image observation sample should be plated with gold film in advance, and the component analysis sample must be plated with carbon film. In general, the sample volume should not be too large (≤5x5x2mm is more suitable).

21. Electronic probe:

Samples for quantitative analysis must be ground, polished, and cleaned. If the sample cannot be polished and polished (which will affect the accuracy of the analysis), it should be explained in advance. In order to facilitate testing and save the machine, the sample should be cut into small pieces first. The sample cannot be cut and must be discussed with the tester first. The test points on the analysis surface should be marked first. When the test position is not marked, only a representative and flat position should be selected for the test. Liquid samples must be concentrated and dried first. The sample to be analyzed must be a solid with stable physical and chemical properties under high-energy electron bombardment, non-decomposed, non-explosive, non-volatile, non-radioactive, non-magnetic. It is best to indicate what elements the sample may contain when sending the sample. The sample must be coated with a carbon film.

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