CN112881457B - Automatic detection device and method for temperature-controlled microemulsion phase diagram - Google Patents

Abstract

The invention discloses an automatic detection device and method for temperature-controlled microemulsion phase diagram, comprising a sample chamber, the sample chamber is inserted into a phase state detection box, a liquid feeder is arranged on the top of the phase state detection box, and a constant temperature water bath is arranged inside. and a stirrer, which is located at the bottom of the sample chamber. The sample chamber is respectively connected with the liquid feeder and the constant temperature water bath. The phase state detection box includes a box body. A light source is arranged on one side of the box body. The other side of the box is provided with a rotating analyzer and a light intensity detector corresponding to the polarizer, and the centers of the light source, the polarizer, the sample chamber, the rotating analyzer and the light intensity detector are located on the same axis A scattered light detector is arranged on the side of the box that is perpendicular to the side where the light source is located, and the line connecting the center of the scattered light detector and the sample chamber is perpendicular to the above axis. The invention judges the phase state of the microemulsion through turbidity, electrical conductivity and the presence or absence of polarized light, thereby reducing the chance brought by visual observation, and saving manpower and time at the same time.

Description

A kind of automatic detection device and method of temperature-controlled microemulsion phase diagram

technical field

The invention relates to an automatic detection device and method of a phase diagram, in particular to an automatic detection device and method of a temperature-controlled microemulsion phase diagram.

Background technique

Microemulsion is a homogeneous system composed of oil phase, water phase, emulsifier and co-emulsifier, and is a thermodynamically stable nano-dispersion system. Microemulsion technology has been widely used in daily chemical industry, tertiary oil recovery, material science, enzyme catalysis and other fields. Due to the characteristics of small particle size and transparency, the application of microemulsion as a lipid-soluble drug carrier in the fields of nanomedicine and biomedicine has also received widespread attention and extensive research.

According to the theory of thermodynamics, to make an oil/water system into an emulsion, energy must be provided by the outside world. Microemulsion is a stable mixed system spontaneously formed by oil phase, water phase, emulsifier and co-emulsifier in appropriate proportions. Its nature and formation mechanism are an important research direction of interface science. Change the amount of system components, the microemulsion will have different phase states. The phase states of the microemulsion are mainly divided into the following types: oil-in-water nanoemulsion; water-in-oil nanoemulsion; bicontinuous nanoemulsion; liquid crystal state and turbid state, the first three are clear state. Phase diagram is the most basic tool to study microemulsion, which describes the relationship between the distribution ratio of each component and the phase state. The detailed phase behavior information of the microemulsion can be obtained through the phase diagram, which is of great significance for the theoretical research and practical application of the microemulsion.

The phase diagram of microemulsion is usually detected by titration method, that is, water is continuously added dropwise to the oil phase containing emulsifier and co-emulsifier, and the boundary points are determined by detecting the change of the phase behavior of the system, so as to draw the phase diagram. In actual detection, simple glass instruments such as test tubes are often used, and the phase behavior of microemulsion at room temperature is mainly judged by visual observation. For some special systems, such as nanoemulsions obtained at higher temperatures, the system temperature is very important for the detection of microemulsion phase behavior.

CN1314957C discloses a detection device for drawing a temperature-controlled phase diagram of a nano-emulsion, which can be used for regulating the operating temperature in the detection of the phase diagram. However, the phase state determination in the detection process is still mainly based on naked eye observation, and the detection steps are more complicated and tedious.

SUMMARY OF THE INVENTION

Purpose of the invention: The purpose of the present invention is to provide an automatic detection device and method for temperature-controlled microemulsion phase diagrams, which are used to improve the accuracy and degree of automatic mechanization of phase diagram detection and improve detection efficiency.

Technical solution: The present invention includes a liquid feeder, a constant temperature water bath, a stirrer, a sample chamber and a phase state detection box, the sample chamber is inserted into the phase state detection box, and a liquid feeder is provided on the top of the phase state detection box , there is a constant temperature water bath and a stirrer inside, the agitator is located at the bottom of the sample chamber, the sample chamber is respectively connected with the liquid feeder and the constant temperature water bath, and the phase state detection box includes a box body. A light source is arranged on one side, a polarizer is arranged between the light source and the sample chamber, and a rotating analyzer and a light intensity detector are arranged on the other side of the box corresponding to the polarizer. , The center of the sample chamber, the rotating analyzer and the light intensity detector are located on the same axis, the scattered light detector is arranged on the side perpendicular to the side where the light source is located in the box, and the scattered light detector is connected with the center of the sample chamber perpendicular to the above axis.

The sample chamber is provided with a plurality of phase state detection windows, which are respectively opposite to the polarizer, the rotating analyzer and the scattered light detector in the phase state detection box. The center of the chamber is located on the same axis, and the line connecting the center of the other phase state detection window and the sample chamber is perpendicular to the axis.

A conductivity meter electrode is inserted into the sample chamber, which can be used to detect the conductivity of the sample.

The outer side of the sample chamber is wrapped with a circulating water heating jacket, and the circulating water heating jacket is provided with a water inlet and a water outlet, which are respectively connected with a constant temperature water bath, and the temperature of the samples in the sample chamber can be controlled by the circulating water heating jacket. .

The sample chamber is provided with a sample inlet and a sample outlet, wherein the sample inlet is connected with the liquid feeder, and the sample inlet and the sample outlet are respectively provided with electromagnetic valves.

The liquid adding device is a micro-injection pump or a peristaltic pump, and the liquid adding method is intermittent liquid adding.

The light emitted by the light source passes through a polarizer, a set of opposite phase state detection windows, a rotating analyzer and a light intensity detector to detect the polarization phenomenon of the sample.

The light emitted from the light source passes through a set of mutually perpendicular phase state detection windows and scattered light detectors to detect the turbidity of the sample.

The stirrer is a magnetic stirrer or a mechanical stirrer, which can stir and mix the samples in the sample chamber.

An automatic detection method for a temperature-controlled microemulsion phase diagram, comprising the following steps:

(1) Weigh the sample according to the composition P _x and place it in the sample chamber;

(2) open the constant temperature water bath and stirrer, heat the sample to the set temperature T, and mix the sample;

(3) Start the phase state detection box, and determine the phase state S ₀ of the sample by detecting the polarization phenomenon, turbidity and electrical conductivity of the sample;

(4) start the liquid feeder to add liquid to the sample chamber, and record the cumulative liquid addition volume _Vi ;

(5) detect the phase state Si of the sample after adding liquid by the phase state detection _box ;

(6) Repeat steps (4)-(5) until no new phase is generated;

(7) Automatically clean the sample chamber;

(8) changing the sample composition P _x , repeating steps (1)-(7);

(9) Turn off all switches;

(10) According to the obtained P _x , _Vi , Si _, find the phase transition point and draw a phase diagram.

Beneficial effects: the present invention judges the phase state of the microemulsion through the detection data of turbidity, electrical conductivity and the presence or absence of polarized light, which can reduce the chance brought by visual observation, and save manpower and time at the same time; The temperature of the microemulsion can be accurately controlled; the sample chamber can be automatically cleaned and can be used repeatedly, saving manpower and consumables; the accurate sample addition record through the liquid dispenser, combined with the accurate determination of the phase state, can be more accurate. Determine the phase transition point to make the phase diagram more accurate.

Description of drawings

Fig. 1 is the overall structure schematic diagram of the present invention;

2 is a schematic diagram of the internal structure of the phase state detection box of the present invention;

FIG. 3 is a schematic diagram of the structure of the sample chamber of the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings.

As shown in Figure 1, the present invention includes a liquid feeder 1, a constant temperature water bath 2, a stirrer 3, a sample chamber 4 and a phase state detection box 5, wherein the sample chamber 4 is inserted into the phase state detection box 5, and the phase state detection box 5. There is a liquid feeder 1 on the top, a constant temperature water bath 2 and a stirrer 3 inside, and the overall integration and integration of the equipment are higher. The liquid feeder 1 is connected to the sample inlet 13 of the sample chamber 4 , the constant temperature water bath 2 is connected to the water inlet 17 and the water outlet 18 of the sample chamber 4 , and the stirrer 3 is located at the bottom of the sample chamber 4 . The stirrer 3 is a magnetic stirrer or a mechanical stirrer, which can stir and mix the samples in the sample chamber 4 . The liquid feeder 1 is used for adding liquid, including water, aqueous solution or organic solution, into the sample chamber 4 . Dosing device 1 is a micro-syringe pump or peristaltic pump. The dosing method is intermittent dosing. After adding an equal amount of liquid 5-50 microliters each time, wait 5 minutes for phase state detection, and then add liquid again. You can set the dosing program by setting the dosing program. Precise, continuous and automatic dosing without manual dripping.

As shown in FIG. 2, the phase state detection box 5 includes a box body 6, a light source 7, a polarizer 8, a rotary analyzer 9, a light intensity detector 10, a scattered light detector 11 and a conductivity meter electrode 12, wherein, The light source 7 is located on one side of the box 6, a polarizer 8 is arranged between the light source 7 and the sample chamber 4, and a rotating analyzer 9 is arranged on the other side of the box 6 corresponding to the polarizer 8 and light intensity detector 10. The centers of the light source 7, the polarizer 8, the sample chamber 4, the rotating analyzer 9 and the light intensity detector 10 are located on the same axis, and the scattered light detector 11 is located in the box 6 on the side perpendicular to the side where the light source 7 is located , and the line connecting the center of the scattered light detector 11 and the sample chamber 4 is perpendicular to the above-mentioned axis. The conductivity meter electrode 12 is inserted into the sample chamber 4 .

As shown in FIG. 3 , the sample chamber 4 includes a sample inlet 13 , a sample outlet 14 , three phase detection windows 15 and a circulating water heating jacket 16 . Water can be added through the sample inlet 13 , a constant temperature water bath 2 and a stirrer 3 The liquid is heated, stirred, and drained from the sample outlet 14 to realize automatic cleaning of the inner wall of the sample chamber 4. The cleaned sample pool can be reused to reduce the loss of the sample tube. The sample inlet 13 and the sample outlet 14 are respectively provided with electromagnetic valve 19. The three phase state detection windows 15 are respectively opposite to the polarizer 8 , the rotating analyzer 9 and the scattered light detector 11 in the phase state detection box 5 , wherein the center of the two phase state detection windows 15 is the center of the sample chamber 4 On the same axis, the line connecting the center of the third phase state detection window 15 and the sample chamber 4 is perpendicular to the axis. The outer side of the sample chamber 4 is wrapped with a circulating water heating jacket 16, which is connected to the constant temperature water bath 2. The circulating water heating jacket 16 is provided with a water inlet 17 and a water outlet 18, and the sample chamber 4 can be connected to the sample chamber 4 through the circulating water heating jacket 16. Temperature control of the sample inside.

The light emitted by the light source 7 passes through the polarizer 8, the two opposite phase state detection windows 15, the rotating analyzer 9 and the light intensity detector 10, which can be used to detect the polarization phenomenon of the sample; the light emitted by the light source 7 passes through the two mutual The vertical phase state detection window 15 and the scattered light detector 11 can be used to detect the turbidity of the sample; the conductivity meter electrode 12 is inserted into the sample chamber 4 and can be used to detect the conductivity of the sample. The phase state of the sample can be determined by detecting the polarization phenomenon, turbidity and electrical conductivity of the sample. In terms of data processing and analysis, the data detected by the liquid dispenser 1, the light intensity detector 10, the scattered light detector 11 and the conductivity meter can be further connected to the computer through the data acquisition card for data acquisition, display and storage.

The phase state detection part of the present invention includes conductivity detection, turbidity detection and polarization phenomenon detection. The sample chamber 4 is provided with three phase state detection windows 15, which are respectively opposite to the light source 7, the light intensity detector 10 and the scattered light detector 11, share a light source 7, and detect the polarization and turbidity of the sample from two vertical directions. The electrodes of the conductivity meter are inserted into the sample chamber 4 for detecting the turbidity of the sample. The phase state detection system can simultaneously detect the conductivity, polarization phenomenon and turbidity changes of the system online, so as to accurately judge the phase state of the system: a. Use the turbidity to quantitatively determine the turbid state and the clear state, and determine that the microemulsion includes oil-in-water range of nanoemulsion, water-in-oil nanoemulsion and bicontinuous nanoemulsion; b. The range of bicontinuous nanoemulsion is determined by the change of electrical conductivity; c, the liquid crystal state is determined by the presence or absence of polarization phenomenon. On the one hand, the system is analyzed through polarized light images, quantitative data of conductivity and turbidity, which improves the accuracy of phase state determination and obtains more detailed surface interface information; on the other hand, the phase state is detected by instrument. To make a judgment, there is no need to continuously observe the experimental phenomenon, which reduces the deviation caused by direct observation with the naked eye and greatly saves manpower.

The automatic detection method of the present invention is:

(1) Weigh the sample according to the composition P _x and place it in the sample chamber;

(2) open the constant temperature water bath and stirrer, heat the sample to the set temperature T, and mix the sample;

(3) Start the phase state detection box, and determine the phase state S ₀ of the sample by detecting the polarization phenomenon, turbidity and electrical conductivity of the sample;

(4) start the liquid feeder to add liquid to the sample chamber, and record the cumulative liquid addition volume _Vi ;

(5) detect the phase state Si of the sample after adding liquid by the phase state detection _box ;

(6) Repeat steps (4)-(5) until no new phase is generated;

(7) Automatically clean the sample chamber;

(8) changing the sample composition P _x , repeating steps (1)-(7);

(9) Turn off all switches;

(10) According to the obtained P _x , _Vi , Si _, find the phase transition point and draw a phase diagram. The phase diagram drawing method is:

1) Take an equilateral triangle ABC;

2) Take 10 equal points P _X on the edge of BC, X=1,2,...9;

₃ ) Determine each composition, such as point P1, the initial ratio is anhydrous state, which is a mixture of B and C to form CP1/BP1=0.1/0.9, that is, C%/B%=1/9;

4) Obtain the sequence P ₁ , _Vi , Si through the automatic detection method of the temperature-controlled _{microemulsion} phase diagram _, find the points TP ₁ , _VT , _ST where the phase state changes according to Si, and add the total volume _VT That is, it is converted into the percentage Q _T of each substance;

5) Determine the phase transition point on AP ₁ according to Q _T ;

6) Determine all phase transition points on AP ₂ -AP ₃ according to steps 3)-5);

7) Draw a phase diagram according to the phase transition points.

Claims (10)

1. An automatic detection device of a temperature-controlled microemulsion phase diagram is characterized by comprising a liquid filler (1), a constant-temperature water bath (2), a stirrer (3), a sample chamber (4) and a phase detection box (5), wherein the sample chamber (4) is inserted into the phase detection box (5), the liquid filler (1) is arranged at the top of the phase detection box (5), the constant-temperature water bath (2) and the stirrer (3) are arranged in the phase detection box, the stirrer (3) is positioned at the bottom of the sample chamber (4), the sample chamber (4) is respectively connected with the liquid filler (1) and the constant-temperature water bath (2), the phase detection box (5) comprises a box body (6), a light source (7) is arranged at one side of the box body (6), a polarizer (8) is arranged between the light source (7) and the sample chamber (4), a rotary polarization detector (9) and a light intensity detector (10) are arranged at the other side of the box body (6) and correspond to the polarizer (8), the centers of the light source (7), the polarizer (8), the sample chamber (4), the rotary polarization analyzer (9) and the light intensity detector (10) are positioned on the same axis, a scattering light detector (11) is arranged on the side surface, perpendicular to the side surface where the light source (7) is positioned, in the box body (6), and the central connecting line of the scattering light detector (11) and the sample chamber (4) is perpendicular to the axis.

2. The device for the automatic detection of the phase diagram of the temperature-controlled microemulsion according to the claim 1, wherein the sample chamber (4) is provided with a plurality of phase detection windows (15) which are respectively opposite to the polarizer (8), the rotary analyzer (9) and the scattered light detector (11) in the phase detection box (5), wherein the centers of one set of the opposite phase detection windows (15) and the sample chamber (4) are positioned on the same axis, and the central connecting line of the other phase detection window (15) and the sample chamber (4) is vertical to the axis.

3. The device for the automated detection of the phase diagram of a temperature-controlled microemulsion according to claim 1 or 2, characterized in that conductivity meter electrodes (12) are inserted in the sample chamber (4).

4. The automatic detection device for the temperature-controlled microemulsion phase diagram according to claim 3, wherein a circulating water heating jacket (16) is wrapped outside the sample chamber (4), and a water inlet (17) and a water outlet (18) are arranged on the circulating water heating jacket (16) and are respectively connected with the constant-temperature water bath kettle (2).

5. The device for automatically detecting the temperature-controlled microemulsion phase diagram according to claim 4, wherein the sample chamber (4) is provided with a sample inlet (13) and a sample outlet (14), wherein the sample inlet (13) is connected with the liquid charger (1), and the sample inlet (13) and the sample outlet (14) are respectively provided with an electromagnetic valve (19).

6. The automatic detection device for the phase diagram of the temperature-controlled microemulsion according to claim 1, wherein the liquid adding device (1) is a micro-syringe pump or a peristaltic pump, and the liquid adding mode is intermittent liquid adding.

7. The automatic detection device of the phase diagram of the temperature-controlled microemulsion according to claim 1, wherein the light emitted by the light source (7) passes through the polarizer (8), a set of opposite phase detection windows (15), the rotary analyzer (9) and the light intensity detector (10) to detect the polarization phenomenon of the sample.

8. The apparatus for the automated phase diagram detection of temperature-controlled microemulsions according to claims 1 or 7, characterized in that said light source (7) emits light through a set of mutually perpendicular phase detection windows (15) and scattered light detectors (11) to detect the turbidity of the sample.

9. The apparatus for the automated detection of the phase diagram of a temperature-controlled microemulsion according to claim 1, wherein the stirrer (3) is a magnetic stirrer or a mechanical stirrer.

10. The detection method of the automatic detection device adopting the temperature-controlled microemulsion phase diagram of claim 1 is characterized by comprising the following steps of:

(1) according to composition P_xWeighing a sample and placing the sample in a sample chamber;

(2) opening the constant-temperature water bath kettle and the stirrer, heating the sample to a set temperature T, and mixing the sample;

(3) starting a phase state detection box, and judging the phase state S of the sample by detecting the polarization phenomenon, turbidity and conductivity of the sample₀；

(4) Starting the liquid charger to add liquid to the sample chamber and recording the total accumulated liquid volume V_i；

(5) Detecting the phase S of the sample after liquid adding through a phase detection box_i；

(6) Repeating steps (4) - (5) until no new phase is generated;

(7) automatically cleaning the sample chamber;

(8) changing the sample composition P_xRepeating steps (1) - (7);

(9) closing all switches;

(10) according to the obtained P_x，V_i，S_iThe phase transition point is found and the phase diagram is plotted.

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