to glucose For example -Instrumax CAD Performance inspection

1. Experiment purpose:glucose-Inspection Instrumax CAD Performance
2. Experimental conditions:

   Instruments:INSTRUMAX Charged Aerosol Detector (CAD)(CADetector a1)

INSTRUMAX Nitrogen Generator g15)

Agilent liquid chromatograph(HPLC-1200)

Ohaus balance (AR1530, precision 0.001g)

Pipette (Finnpipette F1 20-200μL)

• 1. Column: Alltech Chrom H+ (hydrogen sugar column,300mm✖7.8mm,8μm)
  2. Reagents: Watsons distilled water
  3. Sample: D-Glucose (CHEM SERVICE, purity 99.5%)
  4. Mobile phase: pure water

1, experimental process

3.1 Experimental conditions

Mobile phase: pure water

Chromatographic column: Hydrogen sugar column,300mm✖7.8mm,8μm

Column temperature:60℃

Flow rate:1mL/min

Sample concentration:glucose 5μg/mL

CAD Conditions

Drift tube temperature:40℃

Atomized air flow:3L/min

Charging airflow:1L/min

Charging current:1μA

Gain：0.05

RF：2.0

Sample configuration process

Weigh 0.100g glucose set 10mL volumetric flask, dissolve it in pure water and dilute it to the mark.10mg/mL sample, to 10mg/mL as mother liquor, gradually diluted to obtain 8mg/mL,7mg/mL,6mg/mL,5mg/mL,4mg/mL,3mg/mL,2mg/mL,1mg/mL sample; to 1mg/mL as mother liquor, gradually diluted to obtain 500μg/mL,400μg/mL,300μg/mL,200μg/mL,100μg/mL sample; to 100μg/mL As mother liquor, dilute it to get 5.0μg/mL sample; to 5.0μg/mL diluted 0.5μg/mL sample, to 0.5μg/mL As mother liquor, dilute it to get 0.1μg/mL Sample.

3.2 Experimental results

3.2.1 Baseline noise and baseline drift

3.2.2 Minimum detection concentration

Sample:5.0μg/mL glucose, injection 10μL

Refer to the following calculation formula to calculate the minimum detection concentration:

3.2.3 linear range

Sample:100μg/mL,200μg/mL,300μg/mL,400μg/mL,500μg/mL;

1mg/mL，2mg/mL，3mg/mL，4mg/mL，5mg/mL，6mg/mL，7mg/mL，8mg/mL，10 mg/mL。

Test procedure:

in turn 100μg/mL,200μg/mL,300μg/mL,400μg/mL,500μg/mL Sample injection liquid chromatograph, make a standard curve based on concentration and corresponding response.

find on the curve glucose concentration greater than 500μg/mL The reading at each point is compared with the measured value at each corresponding concentration point. The magnitude difference is 5%The concentration when is used as the upper limit of detection C_H, according to the obtained minimum detection concentration, it is the detection lower limit C_LValue, C_H/C_LRatios are in the linear range.

Calculate the measured sample concentration according to the standard curve

From this we can get C_Hfor 3.00×10^-3 g/mL，C_Lfor 4.48×10^-8g/mL, linear range=C_H/C_L

3.2.4 Overall machine performance (qualitative, quantitative repeatability)

Sample:5μg/mL,100μg/mL glucose sample,5μg/mL Inject 10μL and 20μL;100μg/mL Inject 5μL

Test procedure: After the baseline is stable, inject a certain volume into the system to obtain glucose Standard solution, continuous measurement 6 times, record the retention time and peak area of the chromatogram, and calculate the relative standard deviation RSD₆。

Test results:

2, summary and discussion

Summary of results

Discussion of results:It can be seen from the noise drift, minimum detection concentration, linear range, repeatability and other results that Instrumax Charged Aerosol Detector (CAD) It has high sensitivity, wide linear range and good repeatability, making it a good tool for detecting non-volatile substances.

3, References

GB/T 26792-2019 liquid chromatograph

JJG 705-2014 high-performance liquid chromatograph