Dissolved Oxygen Analyzers

Dissolved Oxygen Analyzers for Sale

Buy used, refurbished, and surplus dissolved oxygen analyzers and DO meters from mLab Supply for water quality testing, environmental monitoring, aquaculture research, fermentation sample analysis, and general laboratory dissolved oxygen measurement. We source portable and benchtop optical and electrochemical dissolved oxygen meters from YSI, Thermo Scientific, Hach, Mettler Toledo, Hanna Instruments, and OHAUS for academic research, environmental, biotech, and industrial laboratory applications. Pricing and availability vary by meter configuration — submit a quote request and we will confirm current sourcing options, configuration details, and lead time.

<section class="mlab-collection-buying-guide">
<h2>How to Choose a Dissolved Oxygen Analyzer</h2>
<p>Selecting a dissolved oxygen analyzer requires matching the instrument's measurement technology, format, and probe compatibility to your specific workflow. Key considerations include:</p>
<ul>
<li><strong>Optical vs electrochemical measurement:</strong> Optical (luminescent) DO sensors require less maintenance than electrochemical sensors and do not consume oxygen during measurement. Electrochemical sensors (polarographic or galvanic) are well established and widely used. Confirm which technology is appropriate for your application and probe availability.</li>
<li><strong>Portable vs benchtop format:</strong> Portable meters are suited for field use and sample collection in the field. Benchtop meters are suited for controlled laboratory workflows with stable power and sample handling.</li>
<li><strong>Probe compatibility:</strong> Confirm probe type, cable length, and connector compatibility for the specific meter before purchasing. Probe inclusion varies by unit.</li>
<li><strong>Temperature compensation:</strong> Dissolved oxygen solubility is temperature-dependent. Confirm the meter supports automatic temperature compensation for your workflow.</li>
<li><strong>Calibration workflow:</strong> Confirm the calibration method (air-saturated water, water-saturated air, or zero-oxygen solution) and calibration accessory requirements.</li>
<li><strong>Data logging and connectivity:</strong> Consider whether onboard data logging, USB, or wireless data transfer is required for your workflow.</li>
<li><strong>Serviceability:</strong> Consider probe/sensor availability, local service support, and parts availability for the specific platform and vintage.</li>
</ul>
</section>

<section class="mlab-collection-technology">
<h2>Optical vs Electrochemical Dissolved Oxygen Measurement</h2>
<h3>Optical Dissolved Oxygen Meters</h3>
<p>Optical dissolved oxygen meters use luminescent sensor technology to measure dissolved oxygen without consuming oxygen during measurement. Optical sensors require periodic sensor cap replacement rather than membrane and electrolyte maintenance, and are generally less sensitive to flow conditions and fouling than electrochemical sensors. They are well suited for field use, low-maintenance workflows, and applications where frequent calibration is impractical. Sensor cap replacement intervals and compatibility vary by platform.</p>
<h3>Electrochemical Dissolved Oxygen Meters</h3>
<p>Electrochemical dissolved oxygen meters use polarographic or galvanic sensors that consume a small amount of oxygen during measurement. They require periodic membrane replacement and electrolyte replenishment, and may require a minimum sample flow or stirring for accurate measurement. Electrochemical sensors are well established across laboratory and field applications and are available from a wide range of manufacturers. Membrane, electrolyte, and probe compatibility vary by platform and must be confirmed before purchasing a used instrument.</p>
</section>

<section class="mlab-collection-format">
<h2>Portable vs Benchtop DO Meters</h2>
<p>Portable dissolved oxygen meters are battery-powered handheld instruments suited for field sampling, environmental monitoring, and applications where samples must be measured in the field or at multiple locations. They typically include a rugged housing and are designed for one-handed operation. Benchtop dissolved oxygen meters are AC-powered laboratory instruments suited for controlled laboratory workflows where stable power, sample handling, and data management are priorities. Benchtop meters may offer larger displays, more calibration options, and greater data logging capacity. Features vary significantly by model and should be confirmed before purchasing.</p>
</section>

<section class="mlab-collection-model-grid">
<h2>Popular Dissolved Oxygen Analyzer Manufacturers and Models</h2>
<p>mLab Supply sources dissolved oxygen analyzers from leading manufacturers including YSI, Thermo Scientific, Hach, Mettler Toledo, Hanna Instruments, and OHAUS. Common models available to source include:</p>
<dl>
<dt>YSI</dt>
<dd>Pro20i, ProODO</dd>
<dt>Thermo Scientific</dt>
<dd>Orion Star A213</dd>
<dt>Hach</dt>
<dd>HQ40d</dd>
<dt>Mettler Toledo</dt>
<dd>SevenExcellence DO</dd>
<dt>Hanna Instruments</dt>
<dd>HI2004 edge</dd>
<dt>OHAUS</dt>
<dd>Starter ST400D</dd>
</dl>
</section>

<section class="mlab-collection-comparison-ph">
<h2>Dissolved Oxygen Analyzers vs pH and Conductivity Meters</h2>
<p>Dissolved oxygen meters, pH meters, and conductivity meters are distinct instrument classes that measure different water quality parameters. Dissolved oxygen meters measure the concentration of oxygen dissolved in a liquid sample. pH meters measure hydrogen ion activity (acidity/alkalinity). Conductivity meters measure the ionic conductivity of a solution. Some multiparameter meters combine two or more of these measurements in a single instrument, but each measurement requires its own sensor and calibration. Confirm the specific measurement capabilities of any instrument before purchasing.</p>
</section>

<section class="mlab-collection-used-refurbished">
<h2>Buying Used and Refurbished Dissolved Oxygen Analyzers</h2>
<p>Used and refurbished dissolved oxygen analyzers can offer significant cost savings compared to new instruments. When evaluating a used DO meter, key inspection points include:</p>
<ul>
<li><strong>Meter condition:</strong> Confirm display, keypad, and housing condition. Damage to the housing may affect water resistance on portable meters.</li>
<li><strong>Probe condition:</strong> Confirm probe body condition, connector integrity, and cable condition. Probe inclusion varies by unit.</li>
<li><strong>Sensor cap or membrane:</strong> Confirm optical sensor cap condition or electrochemical membrane condition. Replacement status varies by unit and is not guaranteed.</li>
<li><strong>Electrolyte:</strong> For electrochemical sensors, confirm electrolyte availability and compatibility with the specific probe.</li>
<li><strong>Cables and connectors:</strong> Confirm cable length and connector type match your workflow requirements.</li>
<li><strong>Calibration accessories:</strong> Confirm calibration cup, bottle, or accessory inclusion. Calibration accessories vary by unit.</li>
<li><strong>Temperature sensor:</strong> Confirm temperature sensor condition and function where applicable.</li>
<li><strong>Data logging:</strong> Confirm data logging capability and data transfer method where required.</li>
<li><strong>Service history:</strong> Request available calibration and service records where available.</li>
</ul>
<p>Probe condition, sensor cap/membrane status, calibration status, and accessory completeness must be confirmed per unit. mLab Supply does not guarantee that any used or refurbished instrument meets specific regulatory or institutional requirements without independent verification.</p>
</section>

<section class="mlab-collection-consumables">
<h2>Probe, Sensor, and Consumable Considerations</h2>
<p>Dissolved oxygen probes and sensors require periodic consumable replacement to maintain measurement performance. Optical sensor caps must be replaced periodically as the luminescent dye degrades over time. Electrochemical membranes and electrolyte must be replaced regularly and may require conditioning before use. Probe storage conditions affect sensor longevity. Replacement consumables are manufacturer- and model-specific and are not interchangeable across brands or probe types. Confirm consumable availability and compatibility for the specific probe and meter before purchasing a used instrument.</p>
</section>

<section class="mlab-collection-applications">
<h2>Applications</h2>
<p>Dissolved oxygen analyzers support a wide range of laboratory and field workflows including water quality testing, environmental monitoring, aquaculture research, wastewater studies, fermentation sample analysis, bioprocess sample testing, food and beverage research, and general laboratory dissolved oxygen measurement. Suitability for specific regulated applications or institutional quality requirements must be confirmed by the buyer and their compliance team.</p>
</section>

<section class="mlab-collection-calibration">
<h2>Calibration, Maintenance, and Verification</h2>
<p>Dissolved oxygen meters require periodic calibration to maintain measurement accuracy. Common calibration methods include air-saturated water calibration, water-saturated air calibration, and zero-oxygen solution calibration. Sensor maintenance includes membrane or sensor cap replacement, electrolyte replenishment for electrochemical sensors, and probe cleaning. Temperature compensation should be verified as part of routine calibration. Performance verification is recommended after relocation or extended storage. Calibration status on used instruments must be confirmed per unit. mLab Supply does not guarantee calibration status on used dissolved oxygen analyzers.</p>
</section>

<section class="mlab-collection-installation">
<h2>Installation and Workflow Planning</h2>
<p>Benchtop dissolved oxygen meters require available bench space, AC power, and appropriate sample vessels or flow-through cells where applicable. Portable meters require charged batteries and appropriate probe storage between uses. Data transfer requirements vary by platform — confirm USB, Bluetooth, or other connectivity options where data logging is required. Software and computer requirements vary by platform and should be confirmed before purchasing.</p>
</section>

<section class="mlab-collection-procurement">
<h2>Procurement and Logistics</h2>
<p>mLab Supply supports institutional procurement workflows including formal quotations, purchase orders, and vendor onboarding documentation. We can source specific dissolved oxygen meter models and configurations on request, including discontinued platforms. Freight and shipping coordination is available. We also purchase surplus and decommissioned dissolved oxygen analyzers — contact us via the <a href="/pages/sell-lab-equipment">Sell Lab Equipment</a> page if you have equipment available.</p>
</section>

<section class="mlab-collection-related">
<h2>Related Laboratory Equipment</h2>
<p>Laboratories sourcing dissolved oxygen analyzers often also require <a href="/collections/environmental-chambers">environmental chambers</a> for controlled-condition testing and <a href="/collections/thermo-scientific">Thermo Scientific laboratory equipment</a> for additional instruments from that manufacturer. Submit a <a href="/pages/request-a-quote">Request a Quote</a> for current availability and pricing, or visit our <a href="/pages/sell-lab-equipment">Sell Lab Equipment</a> page if you have surplus dissolved oxygen analyzers or other lab equipment to sell.</p>
</section>

<section class="mlab-collection-faq">
<h2>Frequently Asked Questions</h2>
<details><summary>What is a dissolved oxygen analyzer?</summary><p>A dissolved oxygen analyzer (or DO meter) is an instrument used to measure the concentration of oxygen dissolved in a liquid sample. Dissolved oxygen measurement is used in water quality testing, environmental monitoring, aquaculture, wastewater analysis, fermentation, and general laboratory workflows.</p></details>
<details><summary>What is the difference between optical and electrochemical dissolved oxygen measurement?</summary><p>Optical DO sensors use luminescent technology to measure dissolved oxygen without consuming oxygen during measurement and require periodic sensor cap replacement. Electrochemical sensors (polarographic or galvanic) consume a small amount of oxygen during measurement and require periodic membrane and electrolyte replacement. Both technologies are widely used — the appropriate choice depends on your application, maintenance preferences, and probe availability.</p></details>
<details><summary>What is the difference between a portable and benchtop DO meter?</summary><p>Portable DO meters are battery-powered handheld instruments suited for field sampling and environmental monitoring at multiple locations. Benchtop DO meters are AC-powered laboratory instruments suited for controlled laboratory workflows with stable power and sample handling. Features, data logging capacity, and probe compatibility vary by model.</p></details>
<details><summary>What should I inspect before buying a used DO meter?</summary><p>Key inspection points include meter housing and display condition, probe body and cable condition, sensor cap or membrane condition, electrolyte availability for electrochemical sensors, calibration accessory inclusion, temperature sensor function, data logging capability, and available service and calibration history. Probe and accessory completeness varies by unit.</p></details>
<details><summary>Are probes included with used dissolved oxygen meters?</summary><p>Probe inclusion varies by unit. mLab Supply does not guarantee that a probe, cable, or sensor is included unless explicitly stated for a specific listing. Confirm probe requirements and compatibility before finalizing a purchase.</p></details>
<details><summary>Are sensor caps, membranes, or electrolyte replaced before sale?</summary><p>Sensor cap, membrane, and electrolyte replacement status varies by unit. mLab Supply does not guarantee that consumables have been replaced unless explicitly stated for a specific listing. Confirm consumable condition and availability when inquiring about a specific instrument.</p></details>
<details><summary>Are used dissolved oxygen meters calibrated before sale?</summary><p>Calibration status varies by unit. mLab Supply does not guarantee that any used instrument has been calibrated unless explicitly stated for a specific listing. Request available calibration documentation when inquiring about a specific instrument.</p></details>
<details><summary>Can mLab Supply source a specific YSI, Thermo Scientific, Hach, Mettler Toledo, Hanna Instruments, or OHAUS model?</summary><p>Yes. We source dissolved oxygen analyzers from YSI, Thermo Scientific, Hach, Mettler Toledo, Hanna Instruments, OHAUS, and other manufacturers on request. Submit a <a href="/pages/request-a-quote">Request a Quote</a> with your preferred manufacturer, model, and configuration requirements and we will confirm current sourcing options and availability.</p></details>
<details><summary>Are refurbished dissolved oxygen analyzers suitable for regulated laboratories?</summary><p>Suitability for regulated environments depends on the specific instrument's condition, calibration status, and your institution's qualification requirements. mLab Supply does not guarantee that any used or refurbished instrument meets specific regulatory or institutional standards without independent verification. Consult your quality and compliance team before purchasing for regulated use.</p></details>
<details><summary>Does mLab Supply coordinate shipping and setup for dissolved oxygen analyzers?</summary><p>Yes. Contact us when requesting a quote to discuss shipping and any setup coordination requirements for your specific location.</p></details>
<details><summary>Can mLab Supply source discontinued dissolved oxygen meters?</summary><p>Yes. We source discontinued and legacy dissolved oxygen meter platforms on request. Submit a <a href="/pages/request-a-quote">Request a Quote</a> with your preferred manufacturer and model and we will confirm current sourcing options.</p></details>
<details><summary>Does mLab Supply purchase surplus dissolved oxygen analyzers?</summary><p>Yes. We purchase decommissioned and surplus dissolved oxygen analyzers and other laboratory equipment. Visit our <a href="/pages/sell-lab-equipment">Sell Lab Equipment</a> page to submit details about your equipment.</p></details>
</section>