Phenol-free acid-fast bacteria solution

Patent metadata

Field	Value
Publication number	US-2025067637-A1
Application number	US-202418943057-A
Country	US
Kind code	A1
Filing date	Nov 11, 2024
Priority date	Dec 24, 2017
Publication date	Feb 27, 2025
Grant date	—

Abstract

The present disclosure relates to acid fast staining compositions which are free from phenol. The present disclosure also related to a method of detecting an acid fast organism in a biological sample comprising: (a) applying an acid fast staining composition to the biological sample, the acid fast staining solution comprising a fuchsin, a base, a surfactant, and an alcohol, and wherein the acid fast staining composition is free from phenol; and (b) incubating the biological sample with the acid fast staining composition for a predetermined amount of time at a predetermined temperature.

First claim

1 . An in vitro method of staining an acid fast organism in a biological sample, the method comprising the steps of:
(a) providing a biological sample from a subject having or suspected of having an infection with an acid fast organism; (b) applying to the biological sample an acid fast staining composition comprising a fuchsin, a base, a surfactant, and an alcohol, wherein an amount of fuchsin in the composition ranges from between about 0.75 w/v % to about 2.75 w/v % by total volume of the composition, and wherein the acid fast staining composition is free from phenol; and (c) heating at least one of the acid fast staining composition or the biological sample to a temperature ranging from between about 30° C. to about 45° C.

2 . The method of claim 1 , wherein the biological sample is incubated with the acid fast staining composition for a time period ranging from between about 10 minutes to about 40 minutes.

3 . The method of claim 2 , wherein the biological sample is incubated with the acid fast staining composition for a time period ranging from between about 12 minutes to about 24 minutes.

4 . The method of claim 1 , wherein between about 100 microliters to about 500 microliters of the acid fast staining composition is applied to the biological sample.

5 . The method of claim 1 , wherein about 200 microliters of the acid fast staining composition is applied to the biological sample.

6 . The method of claim 1 , further comprising the step of deparaffinizing the biological sample prior to applying the acid fast staining composition.

7 . The method of claim 1 , further comprising the steps of
(d) applying a decolorizing solution including an alcohol and an acid to the biological sample; and (e) applying a secondary stain including a dye and a weak acid to the biological sample.

8 . The method of claim 1 , further comprising the step of imaging the biological sample.

9 . The method of claim 1 , wherein the acid fast staining composition is applied with an automated staining system.

10 . The method of claim 1 , wherein the fuchsin is present in an amount ranging from between about 0.75 w/v % to about 2.75 w/v % by total volume of the acid fast staining composition; the base is present in an amount ranging from between about 0.05 w/v % to about 0.5 w/v % by total volume of the acid fast staining composition; and the surfactant is present in an amount ranging from between about 0.5 w/v % to about 4 w/v % by total volume of the acid fast staining composition.

11 . A method of staining a sample disposed on a slide with an automated staining apparatus comprising:
(a) dispensing an acid fast staining solution onto the sample, the acid fast staining solution comprising (i) fuchsin present in an amount ranging from between about 0.75 w/v % to about 2.75 w/v % by total volume of the acid fast staining solution; (ii) a base present in an amount ranging from between about 0.05 w/v % to about 0.5 w/v % by total volume of the acid fast staining solution; and (iii) a surfactant present in an amount ranging from between about 0.5 w/v % to about 4 w/v % by total volume of the acid fast staining solution, and wherein the acid fast staining solution is free from phenol; and (b) removing the acid fast staining solution from the slide.

12 . The method of claim 11 , wherein between about 100 microliters to about 500 microliters of the acid fast staining solution is applied to the biological sample.

13 . The method of claim 11 , wherein the sample is incubated with the acid fast staining solution for a period of time ranging from between about 10 minutes to about 30 minutes.

14 . The method of claim 13 , wherein the sample is incubated at a temperature ranging from between about 30° C. to about 45° C.

15 . The method of claim 11 , wherein the method further comprises dispensing a decolorizing solution comprising an alcohol and an acid onto the sample.

16 . The method of claim 11 , wherein the method further comprises dispensing a secondary stain composition comprising a dye and a weak acid onto the sample.

17 . The method of claim 11 , wherein the method further comprises deparaffinizing the sample prior to application of the acid fast staining solution.

18 . The method of claim 11 , wherein the method further comprises applying a coverslip to the sample disposed on the slide.

19 . An apparatus comprising at least one dispenser configured to dispense an acid fast staining solution that is free from phenol onto a microscope slide, wherein the acid fast staining solution comprises (a) fuchsin in an amount ranging from between about 0.75 w/v % to about 2.75 w/v % by total volume of the acid fast staining solution; (b) a base in an amount ranging from between about 0.05 w/v % to about 0.5 w/v % by total volume of the acid fast staining solution; and (c) a surfactant in an amount ranging from between about 0.5 w/v % to about 4 w/v % by total volume of the acid fast staining solution.

20 . The apparatus of claim 19 , further comprising at least one assembly adapted to heat the microscope slide.

Assignees

• Ventana Med Syst Inc

Inventors

• Keshwani Malik
• Klein Eric
• Kosmeder Ii Jerome W
• Mehta Parula
• Sacchetti Dominic

Classifications

• G01N2001/302

  Stain compositions · CPC title

• G01N33/5091

  for testing the pathological state of an organism · CPC title

• G01N1/30 Primary

  Staining; Impregnating {; Fixation; Dehydration; Multistep processes for preparing samples of tissue, cell or nucleic acid material and the like for analysis} · CPC title

• C12Q1/04 Primary

  Determining presence or kind of microorganism; Use of selective media for testing antibiotics or bacteriocides; Compositions containing a chemical indicator therefor {(C12Q1/6897 takes precedence)} · CPC title