TOC Analyzers and Real-Time Microbial Detection

    TOC Analyzers and Real-Time Microbial Detection

    Real-time, at-line detection of microbial contamination and total organic carbon (TOC)


    TOC Analyzer and Microbial Detection Analyzer FAQs

    Ensuring that water used in your production and processes meets both your production standards and legal regulations is critical to your operations. The right on-line and at-line equipment can replace time-consuming, costly and error-prone manual sampling. Two critical measurements related to organic contamination are bioburden and total organic carbon. METTLER TOLEDO offers a range of continuous, on-line sensors for total organic carbon analysis and at-line analyzers for microbial detection related to bioburden measurements.

    What is total organic carbon?

    Total organic carbon, or TOC, is a measurement of all of the organic contaminants in a water system. It is one indicator of water quality in pharmaceutical manufacturing, semiconductor manufacturing and power generation.

    Why measure total organic carbon in water?

    Measuring TOC in water is important because high rates of TOC in water can degrade water purification systems, contaminate batches, reduce production yields and damage equipment.

    I already measure conductivity; why do I need to measure TOC?

    Conductivity measurements are great for identifying ionic contamination, but generally organic contaminants are non-ionic. Therefore, they cannot be detected with standard conductivity measurements.

    How does a Total organic carbon analyzer (TOC analyzer) work?

    Typically, TOC is measured off-line in a lab for high concentrations (>1 ppm), and on-line for concentrations lower than 1 ppm. On-line detection is quicker than lab methods; therefore, you can more quickly make a change to your process when there is an unexpected increase of TOC.

    METTLER TOLEDO TOC analyzers use UV oxidation and differential conductivity measurement. High performance digital conductivity sensors take a conductivity measurement before and after a sample of the water is exposed to 185 nanometer UV light. The UV exposure breaks down the bonds in the non-ionic, organic compounds (oxidation) which creates carbon dioxide and water. This further forms carbonic acid, which dissociates into ionic conductive species. The increase in conductivity after oxidation is directly proportional to TOC measurement.

    Where should I measure TOC?

    TOC analyzers are typically used to measure throughout the water purification process and at specific points in the water usage process. Key applications include:

    • Monitoring membrane efficiency after reverse osmosis
    • Monitoring resin life and efficiency after deionization
    • Ensuring low organic levels are maintained after storage in pure water tanks after final polish
    • Ensuring low organic levels prior to water return during recycle and reclaim processes.
    • Monitoring UV light efficiency after TOC destruction in water purification
    • Ensuring final water quality before the point of use distribution lines

    What is bioburden?

    Bioburden is the number of bacteria living on a non-sterile surface. When talking about water, we generally discuss microbial contamination, which is a measurement of the bacteria in water. Microbial contamination regulations vary substantially by the use of the water that is being analyzed, for example, wastewater and pharmaceutical water have very different requirements for eliminating microbial contamination.

    How do I measure microbial contamination of water?

    There are now numerous ways to measure microbial contamination of water, and USP recommends specific ways of doing so for pharmaceutical waters. Traditionally plate count methods are widely used; however, they are prone to error and can take 5-7 days for results. Plate counting also requires the formation of a colony forming unit (CFU), which is an estimation of total bacteria present in the sample. Another way of measuring microbial contamination in water is through laser-induced fluorescence, with a microbial detection analyzer. This measures the total number of cells that are present in the sample. Systems that use this type of technology allow for at-line, real-time monitoring of microbial contamination in pharmaceutical waters by identifying auto fluorescent units (AFUs).

    What are auto fluorescent units?

    Auto fluorescent units are individual microorganisms and are reported in cells/mL. The 7000RMS illuminates the sample with a laser resulting in the fluoresce of metabolites (NADH and riboflavin) which are present in all bacteria. At the same time, Mie scattering measurements determine the size of the particle that is illuminated by the laser. With the use of algorithms and sample processing, the 7000RMS analyzes the fluorescence spectrum and the size of the particle to determine that a microorganism is or is not present. If present, it is reported as an AFU.

    What are the different types of water used in pharmaceutical production?

    There are several different types of water that are used in pharmaceutical production. Each is used at different steps in the process and has different specifications for purity. Some of the most common include:

    • Purified Water (PW): water that has been processed to remove impurities to low levels
    • Water for Injection (WFI): water used as an excipient in the production of parenteral medications
    • Ultrapure Water (UPW): water that has been purified to extremely low levels of impurities that must meet very strict specifications. UPW conductivity is 0.055 µS/cm at 25ºC (18.2 MOhm)
    7000RMS Microbial Detection Analyzer
    5000TOCi Total Organic Carbon Analyzer
    450TOC Portable Total Organic Carbon Analyzer

    7000RMS Microbial Detection Analyzer

    5000TOCi Total Organic Carbon Analyzer

    450TOC Portable Total Organic Carbon Analyzer

    Laser-induced fluorescence technology delivers instant detection and quantification of micro-organisms. Reduces lab measurements and increases process control.
    Provides continuous, fast and reliable monitoring of TOC levels in various applications. With continuous on-line measurements, the 5000TOCi sensor ensures TOC excursions will not be missed.
    Employing proven continuous measurement technology, the 450TOC provides the fastest response available in a portable analyzer. Providing fast, convenient and affordable multi-point sampling capabiliti...
    High sensitivity
    Measurement of individual cells, reported as Auto Fluorescent Unit (AFU). Limit of detection is one AFU.
    Easy to use
    No sample preparation, staining or incubation required. Touchscreen operation.
    Configurable to requirements
    User-defined alarm and alert thresholds.
    Real-time Microbial Detection
    Results every two seconds.
    Meets USP <643>, <645>, EP 2.2.44, ChP and JP16 requirements
    for the pharmaceutical industry
    Drastically reduces record keeping for release of water
    through simplified data collection with innovative Peak and Average measurements
    Improves the quality and reliability
    of calibration and System Suitability Testing (SST)
    Interfaces with the M800 multi-parameter analyzer/transmitter
    Reduce sampling time by 75%
    or more with on-the-spot results that eliminate lab analysis delays
    Dual USB ports allow simultaneous USB printer operation
    and data recording to a USB memory stick
    Fully compliant with USP<643>, EP2.2.44, Ch P
    and JP16 to meet pharmaceutical industry regulatory requirements
    1500RV Rinse Verification System
    4000TOC Total Organic Carbon Sensor
    TOC Pump Module

    1500RV Rinse Verification System

    4000TOC Total Organic Carbon Sensor

    TOC Pump Module

    The 1500RV Rinse Verification System is a fully integrated solution for verification of Total Organic Carbon and conductivity of Clean-In-Place final rinse water.
    Uses proven ultraviolet (UV) oxidation with differential conductivity to effectively determine TOC concentrations. Together with M300 single-channel transmitter offers a cost-effective solution.
    Provides a highly stable, metered flow of process water to the TOC sensor to ensure reliable and consistent TOC measurement performance.
    Reduce CIP Costs
    by immediately verifying completion of your final rinse with real-time measurements for TOC and conductivity, and reduce water and energy usage during the rinse process
    Maximize Production System Uptime
    with on-the-spot results showing the success of your rinse process, and immediately restore the production system to operation with minimal risk
    Quickly complete installation and startup
    with a fully integrated, turn-key solution combining TOC and conductivity measurement without complex engineering
    Provides a cost-effective solution for continuous TOC monitoring
    to meet requirements of major pharmacopeias
    Easy and economical integration into water purification make-up and distribution systems
    Designed for simple interface with single-channel M300 transmitter
    for process measurement in real time
    For applications where system pressure is too low to provide
    adequate flow through the TOC sensor
    For low-pressure applications where system pressure may vary routinely during operation
    TOC Analyzer - Monitoring Total Organic Carbon White Paper
    Pharmaceutical Water guide
    TOC Analyzer - Measuring Bioburden Online
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