​MICRONAUT AM
The increasing prevalence and severity of fungal infections in healthcare scenarios requires a standardized routine antifungal susceptibility test (AFST) in the microbiology lab. The MICRONAUT-AM system uses MIC plates for the automated or manual susceptibility testing of yeast and cryptococci.

Based on the broth microdilution (BMD) method, the MICRONAUT-AM Antifungal Agents MIC plates provide the optimal tool for phenotypic quantification of the minimum inhibitory concentration (MIC) of up to 9 antimycotics in a single run.

The MICRONAUT-AM system uses susceptibility testing based on the rehydration of antimycotics by adding a standardized yeast or cryptococcal suspension. After incubation of 24-48 hours at 35-37ºC the plates are ready to be measured either photometrically or visually. A special vacuum drying process is used, meaning the plates can be stored at a room temperature of 15-25°C for up to 24 months from the date of production.
The MICRONAUT-AM system features susceptibility testing of up to 9 antimycotics in up to 11 concentrations following the MIC procedure.
It contains highly effective antifungal agents like anidulafungin, caspofungin and posaconazole. Addition of an AST indicator and the included negative control simplify the visual as well as the photometrical reading.
The MICRONAUT-RPMI medium improves the growth of the yeast and cryptococci delivering interpretation according to EUCAST guidelines after 24-48 hours for yeast and 48-72 hours for cryptococci.

MICRONAUT broth microdilution plates have been evaluated for use with Aspergillus in a UK laboratory.

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​ A UK evaluation by a team from the Royal Brompton and Kings College hospitals showed good correlation between our MICRONAUT AM broth dilution product, based on EUCAST, and the CLSI approach.

Comparative Evaluation of Micronaut-AM and CLSI broth microdilution method for antifungal susceptibility testing of Aspergillus species against four commonly used antifungals.
Ali Nuh, Newara Ramadan, Silke Schelenz, Darius Armstrong-James
doi: https://doi.org/10.1101/811901

comparative_evaluation_of_micronaut-am_and_clsi_broth.pdf
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poster_-aspergillus.pdf
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​EUCAST​
This a copy and paste direct from the EUCAST website;
'Methods of antifungal susceptibility testing
It is recommended that broth micro dilution is used to perform antifungal susceptibility testing of yeasts and moulds.'.
  All interpretation is according to EUCAST where EUCAST values are available

Micronaut AM MIC provides laboratories with the possibility to determine the MIC  of up to 9 antimycotics on a single plate.
​For details of antimycotics included download attached file.  Alternatively with the top 6 agents only, two  samples can be processed on a single plate product code M/E1-832-040
All 9 agents are available on a single plate. for a  single sample in product code M/E1-831-040

The method used  is broth microdilution described in ISO 20776-1:2006 referred to in EUCAST documents.​​

EUCAST or CLSI?
Comparison of Two Commercial Colorimetric Broth Microdilution Tests for Candida Susceptibility Testing: Sensititre YeastOne versus MICRONAUT-AM
'In this study, it was not possible to evaluate which colorimetric broth microdilution method was more correct because SY is evaluated against the CLSI reference method, while M-AM is evaluated against the EUCAST reference method. The important statistically significant differences in test results between both systems do however expose a significant impact on local antifungal susceptibility patterns, on antifungal use and even on in-hospital empirical guidelines when one or the other commercial system is implemented in the clinical laboratory.'

LINK

Features and benefits 
• Standardized MIC determination of antifungal agents with the newly composed MICRONAUT 1640 medium + MOPS + Glucose for application in routine laboratory diagnostics.

• Due to the spectrum of antifungal agents, the MIC plate is appropriate for testing yeasts and cryptococci originating from hospital and community acquired infections 

• Growth of the fungi is indicated by a color change from blue to pink mediated by the AFST indicator supplemented to the test medium.

• Easy visual or photometric reading and evaluation of the AFST results is provided by the colour change of the AST indicator 

• The MICRONAUT software provides reading, evaluation and interpretation according to the latest EUCAST criteria.
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​​Shelf life and storage
• Shelf life: 24 months from date of production
• Storage: at room temperature (15-25°C)

Procedure
​BioConnections has been helping UK laboratories implement manual broth microdilution  for several years. 

• Prepare a 0.5 McFarland bacteria suspension in NaCl
• Transfer an aliquot into MICRONAUT-RPMI 1640 medium + MOPS + Glucose
• Add AST indicator (Redox dye)
• Inoculate the MICRONAUT-AM Antifungal Agents MIC plate
• Incubate for 24 hours for yeast and 48 hours for Cryptococci at 35-37°C
• Read the result visually or measure photometrically

Broth microdilution is the gold standard of MIC testing
​ Broth microdilution is the gold standard of MIC testing, for small numbers of samples it is quite simple and is finding a place in getting the correct MIC for pseudomonads, cystic fibrosis isolates, carbapenemases, fungi and glycopeptides.
 BioConnections has been helping UK laboratories implement manual broth microdilution  for several years. Our range of MICRONAUT plates covers both antifungal and antimicrobial agents.
This video shows how simple and inexpensive broth microdilution can be for those critical samples.

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