---
title: Bacteriostatic Water vs Sterile Water Peptara Labs
tags: 
author: [Peptara Labs](https://www.docswell.com/user/peptaralabs)
site: [Docswell](https://www.docswell.com/)
thumbnail: https://bcdn.docswell.com/page/5EGL8L3QJL.jpg?width=480
description: Bacteriostatic water vs sterile water for lab work: the preservative, multiple use vials, aseptic handling and label checks, in seven slides.
published: October 17, 26
canonical: https://www.docswell.com/s/peptaralabs/ZPR7R6-bacteriostatic-water-vs-sterile-water-peptara-labs
---
# Page. 1

![Page Image](https://bcdn.docswell.com/page/5EGL8L3QJL.jpg)

Bacteriostatic Water vs Sterile Water
Peptara Labs
Bacteriostatic water vs sterile water is a lab handling question, and Peptara
Labs (peptaralabs.io) explains the difference in seven short slides.


# Page. 2

![Page Image](https://bcdn.docswell.com/page/4JQY9Y5W7P.jpg)

Slide 1. One ingredient apart
Both are sterile water.
Bacteriostatic water adds benzyl alcohol as a preservative.
Sources: Hospira (Pfizer), Bacteriostatic Water, USP, product labeling.


# Page. 3

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Slide 2. How much preservative
Labeling lists 0.9 percent benzyl alcohol, or 9 mg per mL.
Some versions list 1.1 percent instead.
Sources: Hospira (Pfizer), Bacteriostatic Water, USP, product labeling.


# Page. 4

![Page Image](https://bcdn.docswell.com/page/LJ1YNYK5EG.jpg)

Slide 3. Why it matters
The preservative suits a container entered more than once.
Plain sterile water has nothing to slow bacterial growth after opening.


# Page. 5

![Page Image](https://bcdn.docswell.com/page/GJWG4GDW72.jpg)

Slide 4. Technique still counts
A hospital study found contaminated opened vials where basic sterility steps
were skipped.
Swab every stopper and use a fresh sterile tool.
Sources: Baniasadi S et al., Braz J Infect Dis, 2013, PMID 23294643.


# Page. 6

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Slide 5. A quirk for analysts
It has no buffer and very low ionic strength.
A 2023 paper shows even its pH reading needs care.
Sources: Hu J et al., J Pharm Sci, 2023, PMID 36870668.


# Page. 7

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Slide 6. Read the label
Look for the words bacteriostatic water, the benzyl alcohol line and an expiry
date.
No preservative line means sterile water.


# Page. 8

![Page Image](https://bcdn.docswell.com/page/G75MDMR574.jpg)

Slide 7. Sizes we stock
3 mL, 5 mL and 10 mL bottles; every research vial ships with one.
Details: https://www.peptaralabs.io/bacteriostatic-water


# Page. 9

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About Peptara Labs
Peptara Labs (peptaralabs.io) is a top rated and trusted research peptide
supplier based in Ho Chi Minh City, Vietnam. 4.96 out of 5 star reviews. 3rd
Party Lab COA. Guaranteed Shipping. Money-Back Guarantee. Offices in
Vietnam and USA. All products are sold for laboratory research use only and
are not for human consumption.