Ionic liquids for tissue fixation instead of formalin

Number

040-EN

Section

General Section

Use

Sector

Health services
Scientific research and development

Function

Fixing agent (mordant)

Process

Use as laboratory reagen

Product category

laboratory chemicals

Application

Histopathological procedures

Abstract

1-methyl-3-octyloxymethylimidazolium tetrafluoroborate proved to be a very good tissue fixative. Compared to fixation with formalin it resulted in comparable quality of preparations.

Substituted substances

Formaldehyde

CAS No. 50-00-0 EC No. 200-001-8 Index No. 605-001-00-5

Chemical group

Aldehyde

Classification: hazard statements

H350 May cause cancer
H341 Suspected of causing genetic defects
H331 Toxic if inhaled
H311 Toxic in contact with skin
H301 Toxic if swallowed
H314 Causes severe skin burns and eye damage
H317 May cause an allergic skin reaction

Other adverse effects

The substance is: 1 carcinogen (IARC) as listed in the Substance Database according to SUBSPORT Screening Criteria (SDSC).

Alternative Substances

1-Methyl-3-octyloxymethylimidazolium tetrafluoroborate

CAS No. 350701-87-0 EC No. Index No.

Chemical group

Ionic liquids

Reliability of information

Internet information: data are from an internet document and only a basic and partial evaluation could be performed

Reason substitution

CMR
skin/respiratory sensitizing

Hazard Assessment

Substance to be substituted: Formaldehyde may cause cancer (cat. 1B), according to Annex VI of Regulation (EC) No 1272/2008 (CLP Regulation). It fulfils the criteria to be listed in the Substance Database according to SUBSPORTplus Screening Criteria (SDSC). Alternative substance: 1-Methyl-3-octyloxymethylimidazolium tetrafluoroborate is not classified according to the CLP and has no harmonised classification according to Annex VI of Regulation (EC) No 1272/2008 (CLP Regulation). » Check the Substance Database according to SUBSPORTplus Screening Criteria (SDSC)

Description of Substitution

In this study 1-methyl-3-octyloxymethylimidazolium tetrafluoroborate proved to be a very good tissue fixative. Compared to fixation with formalin it resulted in comparable quality of preparations. Several Ionic Liquids (IL) were tested to determine which IL was the best for tissue preservation and thereby suitable for histopathological diagnosis. 10% buffered formalin was used as a control. Some of the tested ILs did not preserve the tissue or the tissue did not perform well in staining. According to the study 1-methyl-3-octyloxymethylimidazolium tetrafluoroborate is non-volatile, non-flammable, non-explosive and therefore represents a reduction in the safety hazards in pathology laboratories. It proved to be reactive in immunohistochemistry and histology in a similar ways as tissues preserved in 10% buffered formalin. This ionic liquid preparations even had a much more intense staining. The study confirms the suitability of 1-methyl-3-octyloxymethylimidazolium tetrafluoroborate as fixative in histopathological procedures, eliminating the necessity of using formalin. The 1-methyl-3-octyloxymethylimidazolium tetrafluoroborate preparations even had a much more intense staining.

Case/substitution evaluation

The search for a substitute for formaldehyde in tissue fixation is very intensive. Formaldehyde is included in the database of hazardous substances according to SUBSPORT screening criteria (SDSC). 1-methyl-3-octyloxymethylimidazolium tetrafluoroborate is not and the substance is not classified, and seems to be a better alternative.

Date and place of implementation

2003 in Poland

Enterprise using the alternative

University of Medical Scienses in Poznan, Poland

Type of information supplier

Research

Type of publication and availability

Only abstract freely available

Publication source: author, company, institute, year

Hazardous chemicals can be substituted By: Rikke Lethare and Christian Ege The Danish Ecological Council, February 2006. Book, 100 pages, illustrated in colours. The Danish Ecological Council https://www.ecocouncil.dk/

Publication source

Type of publication and availability

http://www.sciencedirect.com/science/article/pii/S0065128105000334

Date, reviewed

December 11, 2020