Method for fluorinating a filter for a pipette tip, pipette tip, associated production method and pipette

Patent metadata

Field	Value
Publication number	US-12005383-B2
Application number	US-201916969288-A
Country	US
Kind code	B2
Filing date	Feb 18, 2019
Priority date	Feb 20, 2018
Publication date	Jun 11, 2024
Grant date	Jun 11, 2024

Abstract

A method for fluorinating a filter for a pipette tip, the filter being made of a solid porous structure made of polyolefin. The method comprises the following steps: (a) placing the filter in an enclosure, (b) creating a vacuum in the enclosure, and (c) bringing the filter into contact with a fluorination agent injected into the enclosure in a gaseous state, the fluorination agent being made up of difluorine F2, the difluorine F2 being injected into the enclosure at a partial pressure between 100 Pa and 10000 Pa and step (c) being done at a temperature between 0° C. and 100° C. A pipette tip comprising a filter modified by the fluorination method, a method for producing such a tip, as well as a withdrawing pipette equipped with such a tip.

First claim

What is claimed is:

1. Method for fluorinating a filter for a pipette tip, this filter being formed by a porous solid polyolefin structure, characterized in that it comprises the following steps:
(a) placing the filter in an enclosure,
(b) creating a vacuum in the enclosure, and
(c) contacting the filter with a fluorination agent introduced in the gaseous state into the enclosure,

in that the fluorination agent consists of difluorine F 2 , in that the difluorine F 2 is introduced into the enclosure at a partial pressure between 100 Pa and 10000 Pa, in that step (c) is conducted at a temperature between 0° C. and 100° C., and further comprising after step (c):
(e 1 ) creating a vacuum in the enclosure, followed by
(e 2 ) contacting the filter with dihydrogen or a mixture comprising dihydrogen, the dihydrogen or mixture comprising dihydrogen comprising dihydrogen being introduced in the gaseous state into the enclosure.

2. Fluorination method according to claim 1 , wherein the polyolefin is chosen from a polyethylene and a polypropylene.

3. Fluorination method according to claim 2 , wherein the polyolefin is polyethylene.

4. Fluorination method according to claim 1 , wherein the difluorine F 2 is introduced into the enclosure at a partial pressure between 500 Pa and 8000 Pa.

5. Fluorination method according to claim 1 , wherein step (c) is conducted at a temperature between 10° C. and 60° C.

6. Fluorination method according to claim 1 , wherein step (c) is carried out for a duration between 1 min and 60 min.

7. Fluorination method according to claim 1 , wherein, during step (c), a number of moles of difluorine greater than or equal to the equivalent number of moles of hydrogen atoms of the polyolefin is introduced.

8. Fluorination method according to claim 1 , wherein the mixture comprises dihydrogen and nitrogen.

9. Fluorination method according to claim 8 , wherein the volume percentage of dihydrogen in this mixture is greater than or equal to 2% vol.

10. Fluorination method according to claim 1 , wherein, during step (e 2 ), a number of moles of dihydrogen less than or equal to the number of moles of difluorine introduced during step (c) is introduced.

11. Fluorination method according to claim 1 , wherein step (e 2 ) is carried out for a duration between 10 min and 2 h.

12. Fluorination method according to claim 1 , wherein step (e 2 ) is conducted at a temperature between 0° C. and 200° C.

13. Fluorination method according to claim 1 , wherein, during steps (b) and (e 1 ), the pressure in the enclosure is less than or equal to 100 Pa.

14. Fluorination method according to claim 1 , wherein step (c) is monitored by infrared spectroscopy.

15. Fluorination method according to claim 14 , wherein step (c) is stopped when this ratio ACH 2 /ACF x reaches a value less than or equal to 15.

16. Fluorination method according to claim 14 , wherein step (c) is monitored by tracking the evolution of the ratio ACH 2 /ACF x of the area of the infrared vibration bands corresponding to the —CH 2 groups over the sum of the areas of the infrared vibration bands corresponding to the —CHF— groups and to the —CF 2 groups.

17. Method for producing a pipette tip comprising a fluorinated filter, the method comprising the following steps:
(i) providing a filter formed by a porous solid polyolefin structure,
(ii) fitting the filter in the pipette tip, and
(iii) fluorinating the filter by implementing the fluorination method according to claim 1 .

18. Fluorination method according to claim 1 , further comprising a step (d) of removing the by-products formed during step (c), steps (e 1 ) and (e 2 ) being performed after step (d).

19. Fluorination method according to claim 18 , wherein step (d) is carried out by degassing the by-products during step (c).

20. Fluorination method according to claim 19 , wherein step (d) is carried out by vacuum degassing the by-products formed during step (c).

21. Fluorination method according to claim 18 , wherein steps (c) and (d) are carried out successively, step (d) of removing the by-products being carried out at the end of step (c).

22. Fluorination method according to claim 18 , wherein step (d) is carried out by chemical trapping of the by-products formed during step (c).

Assignees

• Gilson Sas
• Univ Clermont Auvergne
• Centre Nat Rech Scient
• Sigma Clermont
• Centre National De La Rech

Inventors

• Batisse Nicolas
• Dubois Marc
• Peyroux Jérémy
• Guieu Presle Béatrice

Classifications

• C08L23/283

  Iso-olefin halogenated homopolymers or copolymers · CPC title

• B01L2300/0681

  Filter · CPC title

• B01L3/0217

  of the plunger pump type · CPC title

• B01D2239/10

  Filtering material manufacturing · CPC title

• B01D2239/0428

  Rendering the filter material hydrophobic · CPC title