What are the commonly used methods for identification of traditional Chinese medicine? Why?
From19th century to 20th century, the most commonly used "four major appraisals" of TCM appraisal.
1.
Original identification, that is, the original planting of traditional Chinese medicine
(
move
)
bioassay
,
Identification of biological sources of traditional Chinese medicine by biological taxonomy
,
Determine its correct scientific name
,
This is the basis of identification of traditional Chinese medicine.
2.
Character recognition is the application of the methods of seeing, touching, smelling and tasting.
,
Traditional Chinese medicine characteristics
,
Including shape,
Observe the size, color, surface, texture, section, smell and other characteristics.
,
As the basis of identification
,
this is mine
country
Summary of long-term rich experience of Chinese medicine workers
,
It is simple, fast and intuitive.
,
Character recognition mainly
Is to observe the complete medicinal materials and decoction pieces.
3.
Microscopic identification, microscopic identification of crude drugs mainly adopts microscopic observation of plants
(
move
)
Cells and groups in pharmacognosy
Fabric structure and cell content
,
Describe microscopic characteristics
,
Establish the basis of microscopic identification to identify genuine products, similar products or uses.
A production method. It is usually used for crude drugs that are difficult to identify only by their characters.
,
Multi-source students with similar personalities and indistinguishable characteristics
Drugs, broken crude drugs, powdered crude drugs
,
There are pills, pills, pills, pills, pills, pills, pills, pills, pills, pills, pills, pills, pills, pills, pills, pills, pills, pills, and so on.
Settings. Microscopic identification is a special technology.
,
Basic knowledge of plant anatomy, plant microchemistry and microscopy is required.
Slice manufacturing technology
,
Microscopic identification is also one of the scientific methods to identify pills and tablets of Chinese patent medicine and to establish quality standards.
one
,
Ensure the quality of Chinese patent medicine
,
It has certain scientific significance and application value.
4.
Physical and chemical identification refers to the use of some physical properties or chemical reactions of chemical components contained in traditional Chinese medicine.
qualitative
And quantitative analysis
,
Generally, it is suitable for drugs with different chemical components, similar properties and no obvious microscopic identification characteristics.
Wood.
Common identification methods of modern Chinese medicine;
For physical reasons,
Chemistry,
With the rapid development of biology and computer, instrumental analysis methods are constantly updated.
,
Ultraviolet light,
Infrared, gas phase, high performance liquid phase, nuclear magnetic resonance, scanning electron microscope, computer image processing and analysis, various
Keywords electrophoresis, isozyme analysis, molecular biology technology,
X
X-ray diffraction, differential thermal analysis and cluster analysis.
Methods and so on have been absorbed into the identification methods of traditional Chinese medicine.
,
Greatly enriched the identification methods of traditional Chinese medicine.
,
Formed the "big four"
Identification "method as the basis.
,
Focus on physical and chemical analysis.
,
Gradually adapt to the modernization of Chinese medicine and help Chinese medicine go global.
Establish a more scientific, perfect and advanced identification system of traditional Chinese medicine.
1.
Chromatography. Chromatography is
20
Born at the beginning of the century, in
60
Since 1980s, it has been used in the analysis of traditional Chinese medicine.
,
After gradual improvement, finally
Be included
1977
chinese pharmacopoeia
,
And the application ratio of future edition of Pharmacopoeia in traditional Chinese medicine and prescription preparation.
Rapid growth
,
It has become one of the most important methods for identification of traditional Chinese medicine. Its theoretical basis is the above chromatographic method.
,
According to chromatographic separation
The method can be paper chromatography, thin layer chromatography, column chromatography, high performance liquid chromatography and gas chromatography.
(
1
) thin layer chromatography
(TLC)
. Quantitative determination of main components in medicinal materials by TLC
,
Has the advantage of low dosage.
,
square
straightforward procedure
,
Wide application range
,
Good reproducibility and the like.
,
In addition to scraping off the spots of the main components on the thin layer.
,
Elute with solvent
After the determination,
,
The content can also be determined directly on the thin-layer column. Thin-layer scanning method is widely used at present.
(TLCS)，
Because elution and other operations are not needed.
,
Thereby being convenient and quick.
,
The measurement sensitivity is high.
(
2
) high performance liquid chromatography
(High Performance Liquid Chromatography)
High pressure liquid chromatography (short for high-pressure liquid chromatography)
Because of its high separation efficiency
,
Fast analysis speed and the like.
,
near
It has been widely used in quantitative analysis of traditional Chinese medicine.
,
It can also play a very good role in the qualitative identification of traditional Chinese medicine.
(
three
) gas chromatography
(GC)
. The mobile phase of gas chromatography is gas.
,
Called carrier gas
,
Nitrogen is generally used more.
,
have
High efficiency, high selectivity, high sensitivity, low dosage and fast analysis speed. For some volatile compounds
TCM syndrome differentiation can give full play to its unique advantages. Such as gas chromatography and mass spectrometry.
(GC/MC)，
Separate the gas phase.
The components were directly input into the mass spectrometer for qualitative identification.
,
In this way, we can not only know the volatility of different Chinese medicines.
Differences in hair composition
no
,
It also includes the names of the same or different components.
2.
Spectroscopy, select a certain wavelength band to pass through the powder or extract of traditional Chinese medicine.
,
Determine the effect of traditional Chinese medicine on this band
Absorb the wavelength and record its absorption spectrum.
,
This is the principle of spectral identification of traditional Chinese medicine.
(
1
) ultraviolet spectrum
(ultraviolet)
The identification method is based on the difference of unsaturated degree of components contained in traditional Chinese medicine.
,
So guide
The shape, peak position and peak intensity of its ultraviolet absorption curve are also different, so as to achieve the purpose of identification. The ultraviolet spectrum has the following characteristics
high sensitivity
,
therefore
,
It can be used to check the purity and impurity limit of traditional Chinese medicine preparations.
,
Is to control the quality of traditional Chinese medicine preparations.
An important means of quantity
,
Using the absorption characteristics of impurities
,
Trace impurities can be sensitively detected.
( 10
-5
g)
The existence of main components or the control of their purity. Multi-solvent ultraviolet spectrometry
：
When identifying traditional Chinese medicine with ultraviolet spectrum, it was found that
,
Some closely related medicinal materials
,
Because there is little difference in composition
,
Ordinary ultraviolet spectrum is difficult to achieve the purpose of identification.
about
,
Multi-solvent ultraviolet absorption can be used.
,
By comprehensively comparing the differences of their maps
,
And a better recognition effect can be obtained.
Fruit.
(
2
) infrared spectrum
(infrared)
. Infrared spectrum belongs to molecular absorption spectrum.
,
It has the advantage of simple sample preparation in the identification of traditional Chinese medicine.
,
The experiment speed is fast, and the atlas is fingerprint, so it is widely used.
(
three
)
fluorescent spectrometry
(FP)
After some components contained in traditional Chinese medicine absorb energy of a certain wavelength under ultraviolet irradiation,
,
And emits light longer than the wavelength of the absorbed light, that is, fluorescence.
,
Record with a fluorescence analyzer at a specific wavelength.
Under radiation
Fluorescence spectra of the same solvent extract of traditional Chinese medicine
,
And compare their differences.
,
Can also achieve Chinese medicine.
Objective To identify the combination of fluorescence and TLC.
,
That is to say, the traditional Chinese medicine extract first passes through a thin layer.
,
Then the thin plate.
let go
what
365 nm
or
254 nm
Observation under wavelength fluorescence
,
Compare the color and distance of point fluorescence or get thinner.
veneer sheet
Placed in a thin-layer scanner
,
Scanning with appropriate excitation and emission wavelengths.
,
Fluorescent scanning of each traditional Chinese medicine can be obtained.
This diagram is used for identification.
,
This method is especially suitable for some medicinal materials containing fluorescent components.
(
four
) nuclear magnetic resonance vibration method
(nuclear magnetic resonance)
, similar to infrared and ultraviolet spectra.
,
It is another form of absorption spectrum.
,
Wavelength is
for
10~ 100
m
Electromagnetic waves in the radio frequency region irradiate molecules.
,
Energy that can produce nuclei in molecules.
level switch
,
Make the nucleus transition from low energy state to high energy state.
,
This is an MRI. Because the ingredients in traditional Chinese medicine are too complicated.
,
Usually choose
Use a solvent-specific extract for analysis.
,
Obtain traditional Chinese medicine
HNMR
Fingerprints.
(
five
) mass spectrometry analysis
(milliseconds
)
. Mass spectrometry is based on charged particles.
(
Namely ions
)
The mass-to-charge ratio is arranged in order.
Forming spectrogram
,
When the molecules of traditional Chinese medicine extract are ionized in some way in the ion source of mass spectrometer
,
Formed positive electrode
Ions accelerate their flight under the action of high voltage electric field.
,
At this time, there are different quality ion beams.
,
After quality analysis
,
According to quality
The ratio of quantity to charge is arranged in order.
,
Then record it by photography or electricity.
,
You can get quality.
Sound spectrogram Different traditional Chinese medicine extracts contain different components.
,
The obtained mass spectra show the radical peaks of molecular ions and further cracks.
The fracture peaks are also inconsistent.
,
Can be identified. This method is accurate and sensitive.
,
The content of main components in the extract is relatively high.
high
,
The experiment cost is also high.
,
Whether it can be used as a common detection method remains to be explored.
3.
Differential thermal analysis
(Differential Thermal Analysis)
. When the research sample and the reference material are heated at the same speed in the same environment
,
Temperature and time.
Relationship between time and heating temperature
,
The analysis results are displayed by thermogram. Compare the difference of thermal spectrum between them.
different
,
along with
Achieve the purpose of identifying traditional Chinese medicine.
,
The sample consumption of this method is small.
,
Only a few milligrams or dozens of milligrams.
,
Therefore, it is particularly important for precious medicinal materials.
appropriate
,
In addition, it is also helpful for the identification of traditional Chinese medicines belonging to different species.
4.
Random amplification
Deoxyribonucleic acid
law
(RAPD)
. Different kinds of creatures that don't live together, even the same kind of plants.
,
that
Deoxyribonucleic acid
Sequence cannot
inequality
,
This is for use.
Deoxyribonucleic acid
It is possible to identify traditional Chinese medicine by analytical techniques.
5.
Scanning electron microscope technology
(scanning electron microscope)
. Using the high resolution of scanning electron microscope
,
A strong sense of three-dimensional observation
,
Brief introduction of sample making
A single feature
,
Distinguish fine medicinal materials from leaf medicinal materials.
6.
electrophoresis
.
According to some charged components in traditional Chinese medicine, such as organic acid, protein, polypeptide, amino acid and biology.
Alkali and enzyme, etc. In a certain degree of electric field.
,
meanwhile
,
Due to the charge of the components contained in each traditional Chinese medicine
quality
(
straight
Electricity and negative electricity
),
Charge and molecular weight are different.
,
Resulting in the swimming direction of each component.
,
Speed and distance
Waiting is different.
,
The number of bands and staining results are different.
,
So as to achieve the purpose of identifying traditional Chinese medicines. According to the support in electrophoresis operation
the same
,
Can be divided into paper electrophoresis.
,
Polyacrylamide silica gel electrophoresis
,
Cellulose acetate film electrophoresis, etc.
,
Among them, polyacrylamide method is used for
Traditional Chinese medicine is widely used in identification.
,
The test equipment required by this method is simple.
,
Strong specificity
,
High sensitivity. Electrophoresis of cells containing polypeptide
It has obvious advantages compared with traditional Chinese medicine identification in protein, but this method is more susceptible to experimental conditions.
loudly
,
Therefore, we must strictly grasp the consistency of experimental conditions.