NeoCide® PC-150 Preservative is a widely used in a variety of IVD applications for control of microbial growth and biofouling. The active ingredient is a 3:1 ratio of 5-chloro-2-methyl-4-isothiazolin-3-one (CMIT) and 2-methyl-4 isothiazolin - 3-one (MIT). Isothiazolones utilize a two-step mechanism involving rapid inhibition (minutes) of growth and metabolism, followed by irreversible cell damage resulting in loss of viability (hours). Cells are inhibited by disruption of the metabolic pathways involving dehydrogenase enzymes. Critical physiological functions are rapidly inhibited in microbes, including growth, respiration (oxygen consumption), and energy generation (adenosine triphosphate synthesis). NeoCide®PC-150 Preservatives attack the central metabolic cycle of the cell, the KRBES cycle, at specific enzyme sites. All bacteria and fungi possess at least some parts of the KREBS cycle, thus NeoCide®PC-150 Preservative represent a highly efficient broad spectrum biocide.
NeoCide®PC-150 Preservative exhibits outstanding antimicrobial activity against bacteria, mold and yeast even algae. The following table gives the minimum inhibitory concentration (MIC) in ppm of active ingredient.
NeoCide® PC-150 Preservative is stable and effective over a wide range of pH, however it is generally more stable over the lifetime of the reagent at acid environment (pH<7) . The stability of the preservative is reduced and sensitive to temperature in mildly alkaline(pH<8.5). When the IVD products pH exceeds 9 and do not recommend the application since it is not stable in the environment of strong alkaline. Additional test maybe required to understand the actual impact in those products without a stable pH during the shelf life. The information presented in this bulletin will help you evaluate PC-150 as a preservative for your
The benefits of isothiazolones have a broad-spectrum antimicrobial activity even against algae. The major disadvantage is unstable in alkaline pH value from 9 to10, the rate of degrade increase with pH value. (CMIT is heat sensitive and alkaline sensitive but MIT is quite stable)
As a general rule, a rise in temperature accelerates the rate of degradation of chemicals. Avoid high temperatures during IVD reagent manufacturing process, add PC-150 when the temperature is at or below 50°C. When the pH value at 7 at room temperature, light can degrade the products (t ½ = 322h), recommend the preservative and IVD products protected from lights.
Different insert solution impacted to degrade, in generally the speed of degrade in water as lake water>river water>seawater>purified water. Sulfated and sulfonated surfactants can accelerate degrade, as a contrast, phosphate can slowdown the process of degrade.
Enhancing agents also included ion of magnesium, cupric, manganese and Sb3+ those can reduce the degrade of CMIT, however Iron worked as reducing agents are detrimental to isothiazolone stability.
Genemill will be pleased to assist you in determining the optimum concentration of preservative for specific IVD product formulations. There is an established history of successful use as a preservative in IVD products of the relationship of pH and temperature (see figure1-4). However, there are some circumstances in which we would advise potential users to confirm preservative stability (such as high concentration of protein or ion).
NeoCide® PC-150 Preservative should be stored at temperatures within the range of 2 to 40°C, recommend to be stored at ambient. Containers should not be exposed to direct sunlight. The opened container should be vertical and keep upside, closed cap after use. Even product is quite stable with high temperature but still recommend keeping product in cool condition or lessening than 25ºC. The information below for reference.
Products stored at 25ºC for 54 months, no detectable loss of active ingredient and no statistic change for the concentration of magnesium salt.
Products stored at 40ºC for 24 months, no detectable loss of active ingredient and no statistic change for the concentration of magnesium salt.
Additional stability acceleration at 55 ºC for 1 month, and showed that the IVD raw materials are stable at elevated temperatures both active ingredient and the concentration of magnesium salt, prolonged storage at high temperatures is not recommended.
NeoCide® PC-150 Preservative is more popular to apply for Hematology Reagents including Diluent, Cleaner, Lyse and some of Clinical Chemistry Assays. The preservative can prefer to add at the beginning of production, and it has synergistic antimicrobial effect with other preservatives like NeoCide BND-10 and NeoCide GML-2, here is recommendation of dose of application in different products.
NeoCide® PC-150 Preservative is used for different IVD reagents and products, including enzyme and antibody. There was virtually no loss of active biocide in horseradish peroxidase (HRP) or alkaline phosphatase (AP). The effects of isothiazolones on antibody binding were studied using purified mouse lgM as the antigen, and goat antimouse lgM linked to HRP as the reporting antibody. Direct effects on binding were determined up to 300ppm active (20 times as recommend dose) had no effect on the extent of antibody-antigen binding. Incubation of HRP linked antibody reagent with 50ppm active preservative for a period of 35 days had no effect on the performance of the reagent when diluted for use in the binding assay.