Antibiotic Medium 9 (USP) - BioReagent

Cat. No.: A1528626

GRADE & PURITY BioReagent

Storage

Room temperature

Shipped In

Normal

Visão geral

For microbiological assay of antibiotic potency. Preparation method: Weigh 50.0 g of this product in 1 L of distilled or deionized water, heat with stirring and boil until completely dissolved, dispense, autoclave at 121°C for 15 minutes. After sterilization, shake well to prevent agar from settling and solidifying at the bottom, then set aside for use.

Specifications

Especificações e pureza

BioReagent

Condições de armazenamento de armazenamento

Room temperature

Enviado em

Normal

Grau

BioReagent

Product Line

biological_products

Application Protocols

Below is a general, literature‑based outline for using Antibiotic Medium 9 (USP) in agar diffusion potency assays. Adjust all steps to your validated SOP and current USP monograph.

A. Medium preparation (agar diffusion)

• Weigh the specified grams per liter (follow label/CoA). Suspend in purified water with stirring.
• Adjust pH as required by the method. Heat as needed to dissolve completely.
• Add agar if not pre‑included. Autoclave using a validated cycle. Cool to ~45–50 °C.
• Pour base layer into sterile plates to a uniform depth; allow to solidify. If a seed layer is used, prepare separately with standardized inoculum.

B. Inoculum standardization

• Grow the compendial test organism to log phase. Adjust turbidity to the method’s standard (e.g., a defined McFarland or OD) to ensure consistent lawn density.

C. Assay setup

• Apply cylinders/discs or cut wells per method. Add standard and sample solutions in replicates across a suitable range to construct a standard curve.
• Incubate plates at the organism‑specific temperature for the prescribed time. Protect from desiccation.

D. Reading and analysis

• Measure inhibition zones with calibrated calipers or an automated zone reader. Calculate potency using the USP‑recommended statistical model (e.g., parallel line assay), verifying linearity and validity criteria.

Note: Include positive/negative controls and perform growth promotion verification as required. For broth assays, adapt volumes and optical density readouts accordingly.

Biological Roles

As a culture medium, Antibiotic Medium 9 (USP) does not have a biological role as a discrete molecule; rather, it provides a defined nutritional and physicochemical environment that supports the growth of specific test microorganisms used in antibiotic potency assays (literature/general).

• Function: Supplies amino acids/peptides, carbohydrates, minerals, and buffering capacity to enable reproducible growth and antibiotic diffusion characteristics in agar or broth formats.
• Target organisms: USP antibiotic assay chapters specify particular indicator strains for each antibiotic (e.g., Bacillus spp., Staphylococcus spp., Micrococcus/Enterococcus, etc.). Medium 9 is selected for those assays where its composition and pH yield suitable growth and assay sensitivity (literature/general).
• Performance attributes:
  • Supports consistent lawn growth in diffusion assays, enabling well‑defined inhibition zones.
  • Maintains pH and ionic conditions that minimize variability in antibiotic activity during the assay window.
  • Provides adequate clarity and gel strength (when used with agar) for accurate zone measurement.
• Quality control: Growth promotion testing confirms the medium’s ability to support characteristic growth of compendial strains within defined time limits. Suitability tests with antibiotic reference standards ensure linear response over the intended concentration range.

Note: Choose the USP‑designated medium number specified in your monograph. Substituting media can alter organism growth dynamics and antibiotic activity, affecting assay accuracy.

Buffer Applications

This product is not a standalone buffer system for analytical chemistry. However, when prepared, the medium includes intrinsic buffering capacity from its salts and nutrient components (literature/general).

• Typical use: pH stabilization during microbiological growth in antibiotic potency assays, as specified by USP methods.
• Not recommended for: Biochemical assays requiring transparent, well‑defined buffers with low UV absorbance or precise ionic strengths. For such applications, use dedicated buffers (e.g., phosphate, HEPES) prepared to analytical specifications.
• Practical guidance: If a USP monograph calls for a specific pH for the prepared medium, adjust with sterile acid/base prior to sterilization, and confirm post‑sterilization pH is within the acceptable range. Do not substitute separate buffer systems unless permitted by the validated method.

For buffer‑centric workflows (chromatography, enzymology), consult appropriate buffering reagents rather than complex media.

Green Alternatives

Green chemistry considerations for microbiological media center on resource efficiency, waste minimization, and biobased content rather than solvent substitution.

• Current product profile: Dehydrated powder formulated for reconstitution minimizes transport mass and volume compared to ready‑to‑use liquid media, reducing shipping emissions (literature/general).
• Potential greener practices (literature/general):
  • Prepare only the volumes needed to reduce disposal of expired media.
  • Use energy‑efficient autoclaves and validate minimum effective sterilization cycles.
  • Employ reusable glassware where compatible with sterility and quality requirements.
  • Implement closed‑loop water systems for cooling to reduce water consumption.
• Alternative media options: Some laboratories adopt animal‑free peptone sources to reduce animal‑derived inputs. If your application allows, consider validated animal‑origin‑free (AOF) formulations of equivalent USP media. Tradeoff: performance equivalence must be demonstrated via GPT and assay suitability.
• Waste management: Autoclave and dispose of biologically contaminated media according to institutional biosafety procedures; consider segregating uncontaminated, expired dehydrated powder for appropriate solid‑waste streams.

Summary: The product already aligns with lower‑impact distribution as a dehydrated medium. The greatest sustainability gains come from right‑sizing batch preparation, energy‑efficient sterilization, and validated, lower‑impact raw materials where permissible.

Pharmaceutical Uses

No therapeutic use. For research and quality‑control laboratory applications only.

Industry context (literature/general):

• Compendial testing: Used in USP‑described microbiological assays for antibiotic potency, supporting lot release and stability testing in pharmaceutical QC labs when validated under site procedures.
• Method standardization: Provides a consistent growth matrix to compare antibiotic activity against USP reference standards.
• GMP considerations: While this listing is for research use only, analogous media in regulated settings require documented lot traceability, growth promotion testing, and adherence to current USP chapters (e.g., microbiological assay procedures).
• Formulation role: None; this is not an excipient or processing aid in drug products. It is a test medium for microbiological analyses.

Procurement notes:

• Verify the exact medium number and preparation instructions required by your monograph (e.g., antibiotic‑specific assay medium choice). Using the wrong USP medium number can lead to non‑conforming results.
• Retain Certificates of Analysis and, where applicable, Certificates of Origin or BSE/TSE statements if your quality system requires documentation of raw material sources.

Physical Properties

Item-specific physicochemical constants for this formulated medium are not assigned as for pure compounds.

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• Solubility: The product is intended to be reconstituted in purified/deionized water (literature/general). Final clarity may vary with composition and sterilization method.
• pH (prepared medium): Not specified for this item; refer to CoA/Spec Sheet. (Literature/general: USP media are adjusted to a defined pH at 25 °C before sterilization, with acceptable ranges verified post-sterilization for assay performance.)
• Density, refractive index, logP, melting/boiling point: Not applicable to a dehydrated medium mixture; Not specified for this item; refer to CoA/Spec Sheet.
• Osmolality (prepared): Not specified for this item; refer to CoA/Spec Sheet. (Literature/general: determined by the salt/sugar content of the formulation.)

Practical notes (literature/general):

• Reconstitution rate improves with gentle warming (≤50 °C) and stirring; avoid overheating that may caramelize sugars or degrade heat‑labile components.
• Autoclaving conditions are chosen to achieve sterility while preserving performance; over‑sterilization can darken the medium and impair growth promotion.
• Use freshly prepared media for potency assays to minimize pH drift and nutrient degradation.

Quality and Grades

• Grade/Purity: BioReagent (item-specific)
  • Meaning (general): BioReagent-grade products are suitable for life science research applications where consistent performance, low bioburden, and controlled impurity profiles are important. While not a pharmacopeial grade per se, this designation supports reproducible microbiological outcomes.
• USP alignment (general): “Antibiotic Medium 9 (USP)” indicates the formulation intent matches the USP antibiotic assay medium specification for designated potency tests. Conformance for any lot should be verified via CoA and, where applicable, growth promotion testing (GPT) results.
• What to check on receipt (recommended):
  • Lot-specific composition statement and preparation instructions
  • pH specification for prepared medium and acceptable post‑sterilization range
  • Sterility test/growth promotion data (if provided)
  • Appearance and reconstitution clarity criteria
• Stabilizers/antimicrobials: Not specified for this item; refer to CoA/Spec Sheet.
• UV/LC background: Not specified for this item; refer to CoA/Spec Sheet. (General: complex media often have significant UV absorbance; not intended as LC solvents.)

Implications: Use this BioReagent-grade medium for research and quality-control method development/verification. For regulated testing, verify suitability with system suitability tests per USP and your QA requirements. Always document lot numbers to ensure traceability in microbiological assays.

Reaction and Applications

This product is not used as a chemical reagent for synthetic reactions. Its applications are microbiological and analytical in nature.

Key uses (literature/general):

• USP antibiotic potency assays: Used as the base medium in cylinder‑plate (agar diffusion) or turbidimetric assays to determine potency of antibiotics against specified test organisms. Medium composition and pH are chosen to provide consistent growth and diffusion characteristics.
• Growth promotion testing (GPT): Verification that the medium supports recovery and growth of target organisms within specified time frames.
• Method verification/validation: Establishes linearity, precision, accuracy, and robustness for microbiological assay workflows in QC laboratories.
• Reference standard calibration: Employed with USP antibiotic reference standards to generate standard curves.

Practical tips (literature/general):

• Prepare medium according to the designated mass per liter and pH instructions; verify pH before and after sterilization as required by the method.
• Avoid prolonged autoclaving that can darken the medium and reduce performance.
• Use consistent agar depth in plates for diffusion assays; variations alter inhibition zone sizes.
• Control inoculum density using standardized turbidity (e.g., McFarland equivalents as specified in methods) to ensure reproducibility.

Note: For research use only. For regulated testing, follow the current USP general chapters and monographs.

Reaction Conditions

Chemical reaction conditions are not applicable. The relevant “conditions” are preparation and use parameters for microbiological assays (literature/general):

• Reconstitution: Dissolve the specified grams of dehydrated medium per liter of purified water (follow label/CoA). Mix thoroughly; adjust pH as required by the method.
• Sterilization: Autoclave using a validated cycle (commonly 121 °C with appropriate hold time). Avoid over‑processing to prevent nutrient degradation and Maillard browning.
• Agar plates (if used): Add agar as directed, sterilize, cool to ~45–50 °C, then pour to a consistent depth to ensure uniform diffusion and zone measurements.
• Inoculum: Standardize test organism density per the USP method (e.g., turbidity standard). Uniform lawn growth is critical for reproducible inhibition zones.
• Assay setup: Employ cylinder‑plate, paper disc, or bore‑plate techniques as specified. Include multiple concentrations of USP reference standards to construct a standard curve for potency calculation.
• Incubation: Maintain the temperature and duration specified for the organism/antibiotic pair. Avoid desiccation of plates; use humidified chambers if needed.
• Readout: Measure inhibition zones with calibrated calipers or automated readers. Perform replicate measurements and apply the prescribed statistical analysis for potency.

Always follow your validated SOPs and the current USP chapter/monograph for organism selection, medium pH, and detailed assay parameters.

Safety and Handling

• GHS classification, pictograms, signal word, H‑statements: Not specified for this item; refer to SDS.
• General hazards (literature/general): Dehydrated culture media can generate dust; inhalation of dust may cause mechanical irritation. Some components are proteinaceous; individuals with sensitivities to peptones/yeast extracts should avoid exposure. Not for human or animal consumption.
• PPE: Lab coat, nitrile gloves, and safety glasses recommended. Use a dust mask or respirator if handling large quantities producing airborne dust (consult SDS for specifics).
• Handling: Avoid creating dust clouds. Prepare media using aseptic technique to prevent contamination. Do not ingest. Avoid contact with eyes and skin.
• Incompatibilities (literature/general): Strong oxidizers and moisture. Store sealed to prevent caking and microbial contamination.
• First aid (overview; defer to SDS): If inhaled, move to fresh air; if on skin, wash with soap and water; if in eyes, rinse cautiously with water; if ingested, rinse mouth and seek medical advice. Provide SDS to medical personnel.
• Hygiene: Wash hands after handling. Decontaminate surfaces with appropriate disinfectants.
• Waste: Autoclave spent media and cultures before disposal per institutional biosafety procedures.

Always consult the product SDS for authoritative hazard and response information.

Solvent Selection

Traditional organic solvent selection is not applicable to this product. The medium is intended to be reconstituted in water for microbial assay use.

• Primary diluent (item intent): Purified/deionized water suitable for microbiological media preparation (literature/general). Avoid high TOC or residual sanitizers that can inhibit growth.
• Water quality (literature/general): Use Type II or better water; low endotoxin and low microbial count are preferred for consistent performance. Degassing is not required, but warming to ~30–50 °C can aid dissolution. Filter sterilization is generally unnecessary because the medium is designed for thermal sterilization; follow your validated procedure.
• When to consider alternatives: If a test method specifies supplementation or alternative preparation (e.g., addition of buffers, divalent cations, or pH adjustments), follow the pharmacopeial monograph or validated SOP. Do not substitute organic solvents; they can inhibit microbial growth and invalidate potency assays.

For applications requiring different ionic strength or buffering capacity, select the appropriate designated USP antibiotic medium number rather than modifying the solvent system.

Storage and Reconstitution

• Storage conditions (item-specific): Room temperature.
• Shipped in (item-specific): Normal.
• Research use note (item-specific): For research use only.

Reconstitution and use (general/literature):

• Reconstitution medium: Purified/deionized water. Use the grams per liter specified on the product label/CoA. Not specified for this item; refer to CoA/Spec Sheet.
• pH adjustment: Adjust to the method‑specified pH before sterilization; confirm pH after sterilization is within acceptable limits.
• Sterilization: Autoclave using a validated cycle appropriate for media. Avoid excessive heat exposure to prevent degradation.
• Plate preparation: For agar applications, cool sterilized medium to ~45–50 °C before pouring. Maintain consistent plate depth.
• Storage of prepared medium: If not used immediately, store plates/broth at 2–8 °C, protected from light and dehydration (literature/general). Define in‑use shelf life per your QC validation.
• Freeze–thaw guidance: Do not freeze dehydrated medium. Avoid freezing prepared agar; it compromises gel integrity.
• Container management: Keep the dehydrated powder tightly closed with desiccant if provided. Minimize exposure to humidity to prevent caking and reduced performance.

Always follow the product label and CoA for lot‑specific preparation instructions and consult current USP methods for assay‑specific requirements.

Structure and Identity

Antibiotic Medium 9 (USP) is a defined-use, complex microbiological medium specified by the United States Pharmacopeia for antibiotic potency assays. As a formulated blend, it does not have a single molecular structure.

• Item status: complex mixture; no single small‑molecule structure
• CAS: Not specified for this item; refer to CoA/Spec Sheet.
• InChIKey: Not applicable (mixture)
• SMILES: Not applicable (mixture)
• Molecular formula: Not applicable (mixture of organic/inorganic nutrients)
• Molecular weight: Not applicable (mixture)
• Synonyms (literature/general): “USP Antibiotic Medium No. 9,” “Assay Medium 9,” “USP AM9.”
• Structural/functional features (literature/general): typically contains peptones/enzymatic digests (amino acids/short peptides), carbohydrate and mineral sources, and buffering salts formulated to support growth of designated test organisms in USP antibiotic assays.
• 2D structure description: not applicable; the product consists of a dehydrated powder blend of multiple constituents rather than a discrete molecule.

Important: Exact composition, lot-specific specifications, and any USP conformity details are provided on the product label and Certificate of Analysis (CoA).

Synthetic Utility

Not applicable as a chemical building block. Antibiotic Medium 9 (USP) is not used as a reagent or substrate in organic synthesis.

For chemists seeking functional reactivity:

• This product contains complex mixtures (peptones, salts, carbohydrates) that are incompatible with most synthetic transformations and purification workflows.
• The medium can interfere with catalysts, extractions, and spectroscopic analyses due to high salt/organic load and UV‑absorbing components (literature/general).

Recommendation: Refer to pure reagents and defined buffers for synthetic chemistry. Use this medium exclusively for microbiological assay environments as intended by USP protocols.

Target Specificity

Not applicable. This product is a culture medium mixture, not a biological targeting reagent (e.g., antibody, probe, or inhibitor). It does not possess molecular target specificity.

For assay specificity in use: The effective “specificity” arises from the combination of the selected test microorganism, the antibiotic under evaluation, and the standardized assay conditions described in the USP, not from the medium itself (literature/general).