Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for measuring content of paracetanol by diazonium coupling process

A technology for acetaminophen and p-aminophenol is applied in the field of spectrophotometric determination of the content of acetaminophen, and can solve the problems of inability to use quantitative determination, inaccurate color development of coupling products, and difficulty for primary analysts to grasp.

Inactive Publication Date: 2009-06-03
TIANJIN VOCATIONAL INST
View PDF0 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The existing method is more suitable for the analysis of high-purity products. For the analysis of paracetamol content in pharmaceutical wastewater, there are shortcomings such as complex equipment, poor stability of results and difficulty for junior analysts to grasp.
[0004] In the 2005 edition of the Chinese Pharmacopoeia, paracetamol is hydrolyzed by acid, and then diazotization coupling reaction is used to qualitatively identify paracetamol. Due to the inaccurate color development of the coupling product, it cannot be used for quantitative determination.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0018] Take 100mL of the waste water sample from the acetaminophen workshop, filter it, add the filtrate into a conical flask, add 20mL of 10% hydrochloric acid, heat and hydrolyze it in a water bath at 90°C for 90 minutes, transfer it to a 1000mL volumetric flask after cooling, and make it up for later use. In addition, the wastewater sample from the acetaminophen workshop was directly diluted 10 times to make a blank solution.

[0019] Use a pipette to take 1.0mL of the sample solution and blank solution into a 50mL volumetric flask, add 1.0mL of 10% hydrochloric acid, 5.0mL of 10% KBr solution, and 1.0mL of 1.0% sodium nitrite solution, shake well, and let stand for 2 minutes Complete the diazotization reaction. Add 1.0 mL of 2% sulfamic acid respectively, and shake until the air bubbles dissipate. Use 10% ammonia water to neutralize the solution to pH 7, then add 2.0mL 10% ammonia water to adjust the pH to 10, add 1.0% alkaline ethyl naphthol solution 1.0mL, and add water...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to a method for measuring the content of paracetanol by spectrophotometry, comprising the steps as follows: a paracetanol sample is hydrolyzed in hydrochloric acid solution so as to generate paraaminophenol; sodium nitrite is used for diazotization and then superfluous sodium nitrite is decomposed; diazo salt and ethyl naphthol are coupled in a pH10-11 buffer solution to generate red azo compound. The maximum absorptive wavelength of the azo compound is 490nm, and the molar absorption coefficient thereof is 1.25 x 10<4>L.mol<-1>.cm<-1>. The method is used for measuring the content of paracetanol in medicine and pharmacy waste water and has the advantages of simple equipment and convenient and fast operation.

Description

technical field [0001] The invention relates to a method for measuring the content of paracetamol by spectrophotometry, in particular to a method for measuring the content of paracetamol in medicine and pharmaceutical wastewater by using ethyl naphthol as a color developing agent, and belongs to the field of industrial analytical chemistry. Background technique [0002] Acetaminophen is the most widely used antipyretic and analgesic drug in the world. China is the largest producer of this product in the world, with an annual export volume of nearly 50,000 tons. Paracetamol is usually produced by the reaction of p-aminophenol and acetic anhydride. The high cost of wastewater treatment has plagued manufacturers for a long time. It is necessary to develop a simple and reliable quantitative analysis method for paracetamol for production process improvement and environmental protection. [0003] There are many methods for determining the content of paracetamol reported in the lit...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): G01N21/78
Inventor 李建生杨艺
Owner TIANJIN VOCATIONAL INST