Disclosure of Invention
The invention mainly solves the technical problem of providing a method for detecting the wave color factor, which not only can avoid a large amount of sample consumption, but also can obtain a mass spectrum result with definite information of the wave color factor peak.
In order to solve the technical problems, the invention provides a method for detecting the glass color factor, which comprises a sample processing step, wherein the sample processing step is to mix a glass color factor-containing sample with a matrix, and the matrix adopts titanium dioxide.
Preferably, the matrix is nano titanium dioxide, more preferably titanium dioxide P25.
As a preferred embodiment of the present invention, the matrix is dispersed in a solvent to prepare a matrix-containing mixed solution, and then mixed with the glass-containing factor sample; preferably, the concentration of the matrix in the matrix-containing mixed solution is 10+/-2 mg/mL.
Preferably, the solvent for matrix dispersion is a mixed solvent of ethanol and an aqueous sodium chloride solution, and more preferably, the mixed volume ratio of ethanol and an aqueous sodium chloride solution is (1 to 2): (1-2), more preferably in a volume ratio of 1:1.
Further preferably, the ethanol is absolute ethanol. More preferably, the mass percent concentration of the absolute ethanol is >99%.
The concentration of the sodium chloride aqueous solution is 0.8-0.9% by mass, more preferably 0.85% by mass.
As a preferred embodiment of the present invention, the glass factor sample in the glass factor-containing sample is a glass factor hydrate.
The bose factor in the bose factor hydrate can be hydrated with water in any ratio. As a specific embodiment, the content of the water in the vitriol hydrate is 25-35% by mass. Further, as a more specific embodiment, the selected glass color factor hydrate has a water content of 30% by mass.
Preferably, the glassy factor-containing sample is obtained by diluting a glassy factor sample, and the diluting solvent is trifluoroacetic acid aqueous solution.
Further preferably, the concentration of the aqueous trifluoroacetic acid solution is 0.05 to 0.15% by mass, and further preferably 0.1% by mass.
Preferably, the dilution factor is 50 to 1000.
The sample processing step includes: mixing the glass-containing factor sample with the mixed solution containing the matrix, wherein the mixing volume ratio is 1: (1-2), preferably 1:1.5.
as a preferred embodiment of the present invention, the method for detecting the wave stain further comprises a detection step, wherein the detection step adopts MALDI-TOF MS for detection.
Preferably, the detection method comprises the steps of loading the treated glass color factor sample, drying and crystallizing, and detecting by using MALDI-TOF MS;
it is further preferred to perform data acquisition in a linear positive ion mode using a Quan TOF I MALDI-TOF MS mass spectrometer for detection.
Still more preferably, MALDI-TOF MS mass spectrometry conditions used for detection are: the focusing quality is 300m/z, the Laser pulse frequency is 1,000Hz, the mass acquisition range is 50-550m/z, the accelerating electric field voltage is-19 kV, the detecting electric field voltage is-0.5 kV, the Laser pulse energy is 15 mu J, and the single spectrogram Laser bombardment times (Laser shots) are 800 times.
The invention also provides application of the wave color factor detection method in detection of the sample containing the glass color factor.
According to the method for detecting the wave color factor, disclosed by the invention, the detection of the wave color factor is carried out through MALDI-TOF MS (nanometer matrix assisted time-of-flight mass spectrometry), so that the defect of a multi-impurity peak spectrogram of the wave color factor can be effectively overcome, and the relative purity of a wave color factor sample can be directly observed and judged.
The technical principle of MALDI-TOF MS is also based on soft ionization, a detection sample and a chemical matrix form a co-crystallization film to form a solid crystallization sample, the co-crystallization film is irradiated by laser, and the matrix absorbs energy from the laser and transmits the energy to biomolecules, namely, the solid crystallization sample is ionized. Therefore, in the detection process, the solid sample after crystallization is distinguished from the disposable loss of the liquid sample, the consumption of the sample is greatly reduced through repeated collection and verification, and the sample amount required by detection is also small, for example, in the embodiment, the test can be carried out by only diluting the sample amount by 1 mu L. When the method is used for detecting the small molecules of the vitriol, the nano titanium dioxide is used as the conductive matrix, the chemical background and noise brought by the chemical matrix are avoided while the ionization process of the molecules is assisted, and the efficiency of collecting the small organic molecular compounds through MALDI-TOF MS is improved.
The invention optimizes the sample processing mode and the detection means aiming at the detection of the small molecule of the vitriol, and realizes the high-efficiency detection of the small molecule of the vitriol through the pretreatment co-crystallization of the nanometer matrix and the MALDI-TOF MS detection means. The method can avoid a large amount of sample consumption, and can perform repeated detection for a plurality of times with the sample; the molecular mass spectrum result obtained by detection can directly give out clear information of the peak of the glass color factor, and the single peak shape can also clearly judge the purity of the sample.
Detailed Description
Reference now will be made in detail to embodiments of the invention, one or more examples of which are described below. Each example is provided by way of explanation, not limitation, of the invention. Indeed, it will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the scope or spirit of the invention. For example, features illustrated or described as part of one embodiment can be used on another embodiment to yield still a further embodiment.
Accordingly, it is intended that the present invention cover such modifications and variations as fall within the scope of the appended claims and their equivalents. Other objects, features and aspects of the present invention will be disclosed in or be apparent from the following detailed description. It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only, and is not intended as limiting the broader aspects of the present invention.
The technical scheme of the invention is described in detail through specific examples.
According to the method, the nanometer matrix is used for detecting the cosmetic micromolecular glass color factor through a time-of-flight mass spectrometer (MALDI-TOF MS), and the detection method can be used for rapidly and accurately detecting the glass color factor in the cosmetic component.
The detected glassy cause sample is usually dissolved in water and is a glassy cause hydrate, wherein the higher the concentration of the glassy cause is, the higher the viscosity of the liquid is, so that the viscosity of the sample is reduced during detection, so as to assist the combination with a matrix, and the faster and uniform solidification is realized to form a crystallization state capable of being ionized better.
Taking a sample of 30% of the vitriol hydrate as an example, the mass percentage of water in the vitriol hydrate is 30%. 1-5. Mu.L of a sample of the vitronectin hydrate was taken and 100-fold diluted with 0.1% (wt%) of TFA solution (aqueous trifluoroacetic acid) to prepare a sample containing vitronectin.
The nanomatrix uses titanium dioxide, preferably P25 TiO 2 . The matrix is required to be prepared into matrix dispersion system and then used, in particular P25 TiO 2 (10mg/mL,50%Ethanol X0.85% NaCl) dispersion prepared by:
(1) Mixing absolute ethyl alcohol with sodium chloride aqueous solution with the mass percent concentration of 0.85% according to the volume ratio of 1:1 to prepare a mixed solvent;
(2) P25 TiO 2 Dispersing into the mixed solvent obtained in the step (1) to obtain the concentration of 10mg/mL.
Mixing the sample containing the vitronectin prepared above with P25 TiO 2 Mixing the dispersion system, and mixing the sample containing the vitronectin with P25 TiO 2 The volume ratio of the mixed dispersion system is 1:1.5, obtaining a detection sample.
In the detection, 2 mu L of prepared detection sample is taken and loaded into the target hole. Instrument mass calibration can use α -cyano-4-hydroxycinnamic acid/CHCA (Sigma). After the sample is crystallized on the target plate, the sample is loaded into a QuanTOF I MALDI-TOF MS instrument, and data acquisition is carried out in a linear positive ion mode.
Preferably, the MALDI-TOF MS detection conditions are:
and (3) collecting machine types: quantf I;
acquisition mode: a linear positive ion mode (Linear Positive Ion Mode);
focusing quality: 300m/z;
laser frequency: 1,000Hz;
the mass range is as follows: 50-550m/z;
acceleration voltage: -19kV;
detection voltage: -0.5kV;
laser energy: 15 mu J
Single spectrum Laser bombardment times (lasers shots): 800.
example 1
The embodiment provides a detection method of the wave color factor, which takes 30% of the wave color factor hydrate as a detection object and adopts P25 TiO 2 For the matrix, detection was performed using MALDI-TOF MS.
The detection steps are as follows:
(1) 1. Mu.L of a 30% sample of the vitriol hydrate was taken, 100-fold diluted with 0.1% (wt%) aqueous TFA, and then left at room temperature for use.
(2) Mixing absolute ethyl alcohol with sodium chloride aqueous solution with the mass percent concentration of 0.85% according to the volume ratio of 1:1 to prepare a mixed solvent; p25 TiO 2 Dispersing in mixed solvent, ultrasonic treating for 15 min, maintaining suspension state, and if precipitate is present, ultrasonic treating again to obtain matrix dispersion system P25 TiO with concentration of 10mg/mL 2 (10mg/mL,50%Ethanol×0.85%NaCl)。
(3) The glass color diluted sample is mixed with the matrix dispersion system, and the volume ratio of the glass color diluted sample to the matrix dispersion system is 1:1.5, vortex mixing evenly to obtain the detection sample.
(4) And (3) loading 2 mu L of the detection sample obtained in the step (3) on a single target hole of the MALDI 96 target hole steel plate, and waiting for drying and crystallization at normal temperature. Typically crystallization times of 1-5 minutes, if it is found that the target Kong Dianyang sample cannot be dried, which may be related to too high a concentration and high viscosity of the sample itself, can be resolved by further diluting the sample and mixing it with the matrix.
1-2. Mu.L of alpha-cyano-4-hydroxycinnamic acid/CHCA (Sigma) can be spotted on the target plate calibration wells as mass calibration samples.
(5) The target plate after crystallization and drying was loaded into a MALDI-TOF MS instrument, and data acquisition was performed in a linear positive ion mode. The MALDI-TOF MS detection conditions are specifically as follows:
and (3) collecting machine types: quantf I;
acquisition mode: a linear positive ion mode (Linear Positive Ion Mode);
focusing quality: 300m/z;
laser frequency: 1,000Hz;
the mass range is as follows: 50-550m/z;
acceleration voltage: -19kV;
detection voltage: -0.5kV;
laser energy: 15 mu J
Single spectrum Laser shots:800.
the obtained detection spectrograms are shown in fig. 2 and 3.
The Molecular Mass (Molecular Mass) of the small molecule compound, vitrein, was 192.21 Da (Dalton). On the MALDI-TOF MS resultsAs shown in FIG. 3, the glassy cause can obtain a definite sodium ion addition peak [ M+Na ] by the auxiliary ionization of the titanium dioxide nanomatrix] + (214.2=192.2+22.0); at the same time, a potassium ion addition peak of 230.3M/z [ M+K ] can be observed] + (230.3=192.2+38.1)。
The result visually shows that the glassy factor molecules occupying the main body have single peak shape, and other existing molecular information in the sample can be observed in a wide range of a spectrogram at the same time so as to assist in judging the purity of the sample.
The detection process of the embodiment is very simple, and the operability is flexible and rapid; meanwhile, the using amount of the sample is in microliter level, so that the sample is saved; the single-hole crystallization of the target plate can be collected for multiple times, and repeated verification is feasible; the full QuanTOF I (Intelligene Biosystem) target plate (common steel plate) can be spotted into 96 holes, and if a large amount of detection samples are needed, the method can also be used for detecting high-flux small molecule samples.
The detection method for the wave color factor provided by the invention detects the glass color factor by using the nanometer matrix-assisted time-of-flight mass spectrometry, and has the following advantages:
1. can effectively solve the problem of spectrogram analysis of multiple peaks of the glassy cause and assist in observing the relative purity of the glassy cause sample.
2. The sample consumption is extremely small under the experimental scheme, and the crystallized solid sample can be subjected to repeated acquisition verification in MALDI-TOF MS technology detection, and high flux is supported.
3. The whole experimental scheme of the method is simple and quick to operate, and the result analysis can be intuitively obtained.
4. When detecting small molecules, nano titanium dioxide is used as a conductive matrix, and the matrix is used for assisting in the ionization process of molecules and simultaneously avoiding chemical background and noise caused by chemical matrix.
The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The above examples illustrate only a few embodiments of the invention, which are described in detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.