Apparatus and method to measure concentration of disinfectant in medical device reprocessing system
A medical instrument processor includes an enclosure, a liquid distribution system, and a disinfectant concentration measuring subsystem. The enclosure is configured to hold a medical instrument. The liquid distribution system is configured to deliver a disinfection solution to a medical instrument within the enclosure. The liquid distribution system has a liquid outlet. The disinfectant concentration measuring subsystem includes a first mixing chamber in fluid communication with the liquid outlet, a pump that is configured to simultaneously pump the disinfection solution and the reagent solution into the first mixing chamber, and a concentration analysis assembly that is operable to determine a concentration of disinfectant in a sample solution that is output from the first mixing chamber. The reservoir is in fluid communication with the first mixing chamber.
1 . A reagent solution, comprising:
(a) sodium sulfite;
(b) phenolphthalein, configured to act as a pH indicator;
(c) 37% hydrochloric acid;
(d) isopropanol; and
(e) water;
wherein the reagent solution is configured for use measuring ortho-phthalaldehyde concentration in a liquid sample, and is further configured to react with excess sodium sulfite to quantitatively generate hydroxide, which is neutralized by a controlled amount of acid.
2 . The reagent solution of claim 1 , comprising about 3% of the sodium sulfite.
3 . The reagent solution of claim 1 , comprising about 0.004% of the phenolphthalein.
4 . The reagent solution of claim 1 , comprising about 0.175% of the 37% hydrochloric acid.
5 . The reagent solution of claim 1 , comprising about 15.7% of the isopropanol.
6 . The reagent solution of claim 1 , comprising about 81.1% of the water.
7 . A ready-to-use reagent solution, comprising a mixed reagent solution of claim 1 , wherein the ready-to-use reagent solution comprises by weight percentage of the ready-to-use solution:
(a) from about 1% to about 4.8% of the sodium sulfite;
(b) from about 0.1% to about 0.3% of sodium bisulfite;
(c) from about 0.06% to about 0.12% of sodium chloride;
(d) from about 0.002% to about 0.008% of the phenolphthalein;
(e) from about 10% to about 20% of the isopropanol; and
(f) the balance of the water;
wherein the ready-to-use solution is formulated to react with ortho-phthalaldehyde that is present in the liquid sample to quantitatively generate hydroxide in the liquid sample.
8 . The ready-to-use reagent solution of claim 7 , comprising:
(a) about 2.78% of the sodium sulfite;
(b) about 0.185% of the sodium bisulfite;
(c) about 0.104% of the sodium chloride;
(d) about 0.004% of the phenolphthalein;
(e) about 15.7% of the isopropanol; and
(f) about 81.2% of the water.
9 . A reagent solution comprising raw materials, wherein the raw materials comprise:
(a) a sulfite selected from the group consisting of sodium sulfite, sodium bisulfite and combinations thereof;
(b) a pH indicator/absorbance species selected from the group consisting of phenolphthalein, 0-cresol phthalein, p-naphtholbenzene, and ethyl-bis(2,4-dimethylphenyl)acetate;
(c) an acid selected from the group consisting of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, organic carboxylic acids and combinations thereof;
(d) isopropanol as a solvent; and
(e) water;
wherein the reagent solution is configured to be mixed to form a ready-to-use solution that is configured to react with ortho-phthalaldehyde concentration in a liquid sample, and is further configured to react with excess sodium sulfite to quantitatively generate hydroxide, which is neutralized by a controlled amount of acid.
10 . The reagent solution of claim 9 , wherein the sulfite is sodium sulfite.
11 . The reagent solution of claim 10 , wherein the sodium sulfite is present at from about 1% to about 5% by weight percentage of the reagent solution.
12 . The reagent solution of claim 9 , wherein the pH indicator/absorbance species is phenolphthalein.
13 . The reagent solution of claim 12 , wherein the phenolphthalein is present at from about 0.002% to about 0.008% by weight percentage of the reagent solution.
14 . The reagent solution of claim 9 , wherein the acid is 37% hydrochloric acid.
15 . The reagent solution of claim 9 , wherein the isopropanol is present at from about 10% to about 20% by weight percentage of the reagent solution.
16 . The reagent solution of claim 9 , comprising by weight percentage of the total weight of the reagent solution:
(a) from about 1% to about 5% of the sodium sulfite;
(b) from about 0.002% to about 0.008% of the phenolphthalein;
(c) from about 0.1% to about 0.2% of the 37% of hydrochloric acid;
(d) from about 10% to about 20% of the isopropanol; and
(e) the balance of the water.
17 . A ready-to-use reagent solution, comprising a mixed reagent solution of claim 9 , wherein the ready-to-use reagent solution comprises:
(a) from about 1% to about 4.8% of the sodium sulfite;
(b) from about 0.1% to about 0.3% of the sodium bisulfite;
(c) from about 0.06% to about 0.12% of the sodium chloride;
(d) from about 0.002% to about 0.008% of the phenolphthalein;
(e) from about 10% to about 20% of the isopropanol; and
(f) a balance of the water;
wherein the ready-to-use solution is formulated to react with ortho-phthalaldehyde that is present in the liquid sample to quantitatively generate hydroxide in the liquid sample.
18 . A reagent solution, consisting of:
(a) a sulfite selected from the group consisting of sodium sulfite, sodium bisulfite and combinations thereof;
(b) a pH indicator/absorbance species selected from the group consisting of phenolphthalein, O-cresolphthalein, p-naphtholbenzene, and ethyl-bis(2,4-dimethylphenyl)acetate;
(c) an acid selected from the group consisting of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, organic carboxylic acids and combinations thereof;
(d) isopropanol as a solvent; and
(e) water;
wherein the reagent solution is configured to be mixed to form a ready-to-use solution configured to react with ortho-phthalaldehyde concentration in a liquid sample, and is further configured to react with excess sodium sulfite to quantitatively generate hydroxide, which is neutralized by a controlled amount of acid.
19 . The reagent solution of claim 18 , wherein:
(a) the sulfite is the sodium sulfite and is present at from about 1% to about 5% by total weight percentage of the reagent solution;
(b) the pH indicator/absorbance species is the phenolphthalein and is present at from about 0.002% to about 0.008% by total weight percentage of the reagent solution;
(c) the acid is the 37% hydrochloric acid and is present at from about 0.1% to about 0.2% of by total weight percentage of the reagent solution; and
(d) the isopropanol is present at from about 10% to about 20% by total weight percentage of the reagent solution.
20 . A ready-to-use reagent solution, consisting of a mixed reagent solution of claim 18 , wherein the ready-to-use reagent solution consists of:
(a) from about 1% to about 4.8% of the sodium sulfite;
(b) from about 0.1% to about 0.3% of the sodium bisulfite;
(c) from about 0.06% to about 0.12% of the sodium chloride;
(d) from about 0.002% to about 0.008% of the phenolphthalein;
(e) from about 10% to about 20% of the isopropanol; and
(f) a balance of the water;
wherein the ready-to-use solution is formulated to react with ortho-phthalaldehyde that is present in the liquid sample to quantitatively generate hydroxide in the liquid sample.
21 . The reagent solution of claim 1 , comprising by weight percentage of the total weight of the reagent solution:
(a) from about 1% to about 5% of the sodium sulfite;
(b) from about 0.002% to about 0.008% of the phenolphthalein;
(c) from about 0.1% to about 0.2% of the 37% hydrochloric acid;
(d) from about 10% to about 20% of the isopropanol; and
(e) a balance of water.