| HS Code | 465929 |
| Chemical Name | trans-4-[(2-Amino-3,5-dibromobenzyl)amino]cyclohexanol monohydrochloride |
| Cas Number | 23828-92-4 |
| Molecular Formula | C13H18Br2N2O·HCl |
| Molecular Weight | 414.56 g/mol |
| Appearance | White or almost white crystalline powder |
| Solubility | Freely soluble in dimethyl sulfoxide; soluble in methanol; sparingly soluble in water; slightly soluble in ethanol; practically insoluble in dichloromethane |
| Ph | 4.0-6.0 (1% w/v aqueous solution) |
| Assay | 99.0%-101.0% on dried basis |
| Identification | Positive by IR absorption and HPLC retention time relative to reference standard |
| Loss On Drying | ≤0.5% w/w |
| Sulfated Ash | ≤0.1% w/w |
| Heavy Metals | ≤10 ppm |
| Related Substances | Each specified impurity ≤0.2%; any unspecified impurity ≤0.1%; total impurities ≤1.0% |
| Residual Solvents | Complies with ICH Q3C limits |
| Microbial Limits | Total aerobic microbial count ≤1000 CFU/g; total yeast and mould count ≤100 CFU/g; absence of Staphylococcus aureus and Pseudomonas aeruginosa |
| Storage | Store in airtight, well-closed containers in a cool, dry place; protect from light |
| Dosage Form Compatibility | Suitable for tablets, capsules, granules, oral liquids, and injectable preparations |
As an accredited Ambroxol Hydrochloride Pharma Grade API for Tablet / Capsule / Granule / Injection, Oral & Injectable factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Ambroxol Hydrochloride Pharma Grade API: 25 kg/drum, double polyethylene-lined fiber drums, for tablet, capsule, granule, oral and injectable use. |
| Container Loading (20′ FCL) | 20′ FCL: Ambroxol Hydrochloride Pharma Grade API loaded on pallets in sealed containers, protected from moisture, secured for safe transport. |
| Shipping | Ambroxol Hydrochloride Pharma Grade API is shipped in sealed, inert containers, protected from moisture and light. Transport under controlled temperature, with proper documentation and compliance for pharmaceutical raw materials. Ensure secure, non-hazardous handling per GMP guidelines for oral and injectable use, with tamper-evident packaging. |
| Storage | Store Ambroxol Hydrochloride Pharma Grade API in a well-closed, light-resistant container, in a cool, dry, and well-ventilated area. Protect from moisture and excessive heat; recommended storage temperature is 15–30°C. Keep away from incompatible materials and ensure container remains tightly sealed when not in use. |
| Shelf Life | Ambroxol Hydrochloride API has a shelf life of 36 months when stored under recommended conditions, ensuring stability for all listed formulations. |
High-shear wet granulation remains the least segregative route for ambroxol hydrochloride tablets when the active particle size distribution is controlled below 100 µm D90 and the dry blend cannot meet Ph. Eur. 2.9.40 content uniformity because of fine-active migration. A 600 L top-drive high-shear granulator is charged with ambroxol hydrochloride, lactose monohydrate and maize starch; dry mixing proceeds at impeller speed 120 rpm and chopper speed 1500 rpm for 5 min. Aqueous binder solution containing 5.0% w/w povidone K30 is delivered at 1.2–1.8 kg/min. Wet massing continues for 60–120 s after binder addition until end-point torque reaches 25–35 N·m; this torque window is used to limit granule density drift across batches. The wet mass is wet-milled through a 1.14 mm conical screen, transferred to a fluid-bed dryer, and dried with inlet air at 65 °C ±5 °C. Drying is stopped at a loss on drying of 1.5–2.5% determined by Ph. Eur. 2.2.32. The dried granules are dry-milled through a 0.8 mm screen and lubricated with 0.5% w/w magnesium stearate for 3 min at 15 rpm. Rotary compression on a 16-station press at 8–12 kN produces tablets with hardness 60–100 N, friability below 0.8% by Ph. Eur. 2.9.7 and disintegration below 15 min by Ph. Eur. 2.9.1. Dissolution testing in 900 mL 0.1 M HCl at 50 rpm using Ph. Eur. 2.9.3 apparatus 2 should show release of at least 80% at 30 min. Granules dried below 1.0% loss on drying generate excessive fines during dry milling, while granules above 3.0% loss on drying show sticking at compression forces above 10 kN. Residual solvents and elemental impurities are controlled by ICH Q3C and ICH Q3D(R2) for the API release.
| Stage | Parameter | Target range | Equipment/test method |
|---|---|---|---|
| Dry blending | Impeller speed | 120 rpm | 600 L top-drive granulator |
| Wet massing | End-point torque | 25–35 N·m | Torque sensor |
| Drying | Loss on drying | 1.5–2.5% | Ph. Eur. 2.2.32 |
| Compression | Compression force | 8–12 kN | 16-station rotary press |
| Dissolution | Release at 30 min | ≥80% | Ph. Eur. 2.9.3 apparatus 2 |
Aqueous film coating of compressed ambroxol hydrochloride tablets uses hydroxypropyl methylcellulose at 2.5% w/w weight gain in a side-vented coating pan at inlet air 60 °C; coating is stopped when tablet bed temperature exceeds 45 °C, and final tablets retain disintegration below 15 min by Ph. Eur. 2.9.1.
For low-dose direct compression, the initial API-to-filler pre-mix is the single largest source of content uniformity failure. Ambroxol hydrochloride at 30 mg unit dose in a 200 mg tablet core is first pre-dispersed with 0.2% w/w colloidal silicon dioxide through a 0.5 mm sieve to reduce agglomerate formation. The pre-mix is blended with spray-dried lactose and microcrystalline cellulose in a 600 L bin blender at 10 rpm for 20 min; final blend uniformity sampling at 10 locations must show RSD below 3.0%. Lubrication uses 0.5% w/w sodium stearyl fumarate for 2 min at 10 rpm, because magnesium stearate over-blending beyond 5 min delays disintegration above 20 min. A 16-station rotary press operating at 60 rpm with 12 kN compression force achieves tablet mass variability below ±2.0% RSD when feed-frame granulation is absent. Hardness is maintained between 60 and 90 N; friability remains below 0.8% per Ph. Eur. 2.9.7, and disintegration below 15 min per Ph. Eur. 2.9.1. Dissolution in 900 mL 0.1 M HCl at 50 rpm by Ph. Eur. 2.9.3 meets 80% release at 30 min. Direct compression is abandoned when ambient RH drops below 30% without humidity-controlled blending; electrostatic charging of the fine active fraction causes two-point blend RSD above 5.0% and visible sticking on the press turret. Published data for this specific ambroxol direct compression platform is limited, but the stated process window is consistent with standard low-dose immediate-release validation runs.
Segregation of ambroxol hydrochloride in capsule-filling lines arises when the active fraction is finer than 100 µm D90 and the lactose-based diluent remains above 150 µm D50, creating percolation-driven fines migration during hopper discharge. Filling on a Zanasi 40E dosator-type machine with size 3 hard gelatin capsules requires a blend conditioned at 45–55% RH; below 30% RH, electrostatic adhesion to dosator pins and capsule shells raises fill weight RSD above 5.0%. The active is pre-blended with 0.25% w/w colloidal silicon dioxide and passed through a 0.5 mm oscillating sieve. Milled lactose monohydrate and pregelatinised starch are added, and the mixture is blended in a 400 L bin blender at 12 rpm for 25 min. Magnesium stearate 0.5% w/w is introduced for 2 min at 12 rpm. Tamping pin settings deliver 120 mg ±3 mg target fill weight; capsule weight uniformity is verified by Ph. Eur. 2.9.5. Dissolution of capsule contents in 900 mL 0.1 M HCl at 50 rpm by Ph. Eur. 2.9.3 reaches 85% at 30 min when the shell disintegrates below 5 min. If shell dissolution exceeds 10 min due to cross-linking, enzymatic incubation using pepsin may be required to distinguish formulation failure from shell-related delay. Over-lubrication beyond 5 min reduces early release by 10–15% at 10 min and is therefore controlled by release verification rather than by fixed blending time alone.
Top-spray fluid-bed granulation of ambroxol hydrochloride granules for single-dose stick packs is constrained by the need to maintain granular dispersibility below 2 min in 200 mL water at 20 °C. In a 120 L top-spray unit with a 1.0 mm nozzle and 2.0 bar atomisation air, 5.0% w/v povidone K30 binder solution is sprayed at 60–100 g/min. Inlet air temperature is held at 65 °C ±5 °C; product temperature remains between 32 and 36 °C to avoid over-wetting and lump formation. Granule moisture at the end of spraying is limited to 12–15%, followed by drying to 1.5–2.5% loss on drying by Ph. Eur. 2.2.32. Dried granules are screened through 0.8 mm and show D10 80 µm, D50 210 µm and D90 420 µm; granules outside this band either flow poorly in the stick-pack feed hopper or disperse too slowly. Stick-pack filling on a vertical form-fill-seal machine at 22 °C and 30% RH yields fill weight RSD below 2.0% for a 1.0 g target fill. Uniformity of dosage units is evaluated per Ph. Eur. 2.9.40. Dissolution testing of the granule sachet in 900 mL 0.1 M HCl at 50 rpm meets 80% release at 30 min. Foil laminate sachets stored at 40 °C/75% RH for 6 months show moisture uptake below 0.5% and D90 change below 10%, indicating adequate barrier properties.
When ambroxol hydrochloride is formulated at 15 mg/5 mL in a sugar-free syrup, replacing propylene glycol with non-crystallising sorbitol alters ionic strength and the unionised preservative fraction, requiring re-buffering at pH 4.5 ±0.2. The vehicle contains sorbitol 35% w/v, glycerol 10% v/v, citric acid monohydrate 0.4% w/v, sodium citrate dihydrate q.s., methyl paraben 0.18% w/v and propyl paraben 0.02% w/v. The active is dissolved in acidified purified water under nitrogen sparging; residual oxygen is kept below 2.0 mg/L to limit oxidative discoloration of the dibrominated benzylamino chromophore. Preservative efficacy is confirmed by Ph. Eur. 5.1.3, and microbiological release follows Ph. Eur. 5.1.4 for oral liquids. Syrup batches filled into amber type III glass bottles with headspace oxygen below 2.0% retain content above 98% of label claim after 12 months at 25 °C/60% RH. Clear PET packaging is not used for this formulation because light transmission above 500 nm accelerates photolytic discoloration; if bottled in clear glass, a 12-month photostability study under ICH Q1B conditions is required to justify the packaging. Sulfite antioxidants may be added at 0.1% w/v only when oxygen cannot be controlled below 2.0 mg/L; sulfite sensitivity and potential incompatibility with trace aldehydes in certain flavor systems must be evaluated.
Ambroxol hydrochloride injection at 15 mg/2 mL is compounded in Water for Injection, adjusted to pH 4.0 ±0.5 with dilute hydrochloric acid, and made isotonic with sodium chloride 0.9% w/v. Osmolality is confirmed at 280–320 mOsmol/L by freezing point osmometry per Ph. Eur. 2.2.35. The solution is sparged with nitrogen to residual oxygen below 0.5 mg/L, passed through a 0.22 µm sterilising-grade PVDF filter, and filled into amber type I glass ampoules under nitrogen. Terminal steam sterilisation at 121 °C for 15 min is acceptable provided pH remains below 4.5; above this pH, free-base precipitation and an increase in dibrominated degradants are observed during forced degradation. Sterility is assessed per Ph. Eur. 5.1.1; bacterial endotoxin testing by Ph. Eur. 2.6.14 uses a lysate sensitivity of 0.06 EU/mL, with the release limit calculated from the dose and compendial monograph requirement. Particulate matter is controlled by Ph. Eur. 2.9.19 with subvisible particle counts below 6000 per container at 10 µm and 600 per container at 25 µm. The closed ampoule is stored below 30 °C and protected from light. In-use incompatibilities are recorded when the injection is diluted with bicarbonate-buffered infusions at pH above 6.0; precipitation of the free base occurs, so dilution is restricted to 0.9% w/v sodium chloride or 5% w/v glucose solution with confirmed final pH below 5.5.
| Quality attribute | Limit/target | Test method |
|---|---|---|
| Appearance | Clear, colourless to slightly yellow solution | Ph. Eur. 2.2.2 |
| pH | 4.0 ±0.5 | Ph. Eur. 2.2.3 |
| Assay | 95.0–105.0% of label claim | Ph. Eur. 2.2.29 |
| Related substances | Single impurity ≤0.2%, total ≤1.0% | Ph. Eur. 2.2.29 |
| Particulate matter | ≥10 µm: ≤6000 per container; ≥25 µm: ≤600 per container | Ph. Eur. 2.9.19 |
| Sterility | No growth | Ph. Eur. 5.1.1 |
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Ambroxol Hydrochloride Pharma Grade API for Tablet / Capsule / Granule / Injection, Oral & Injectable is a single-entity active substance used in mucolytic solid oral and parenteral dosage forms. The chemical structure is trans-4-[(2-amino-3,5-dibromobenzyl)amino]cyclohexanol hydrochloride, CAS 23828-92-4, with the molecular formula C13H18Br2N2O·HCl and a relative molecular mass of 414.56 g/mol. The API is released as a white or almost white crystalline powder. The hydrochloride salt is freely soluble in water and methanol, sparingly soluble in ethanol, and practically insoluble in dichloromethane. Manufacturer grade designations may include standard unmicronized, micronized, and low-endotoxin injectable material; these codes are supply-chain classifications rather than pharmacopoeial names and are assigned on the basis of particle size distribution, bioburden, and bacterial endotoxin limit. The API is subject to the general monograph Ph. Eur. 2034 for substances for pharmaceutical use. For US submissions, drug substance laboratory documentation is maintained under 21 CFR 211.160, while EU manufacture follows EudraLex Volume 4 Part II. Typical marketed strengths include 30 mg and 60 mg tablets, sustained-release capsules containing 75 mg, oral solution at 15 mg/5 mL, and injectable solution at 15 mg/2 mL or 7.5 mg/mL.
Release testing for the API is aligned with the European Pharmacopoeia monograph for Ambroxol hydrochloride and with current ICH Q3C residual solvent guidance and ICH Q3D elemental impurity control. A representative release panel includes appearance, identification, assay, related substances, loss on drying, sulfated ash, residual solvents, elemental impurities, and microbial enumeration. Identification employs infrared absorption spectrophotometry according to Ph. Eur. 2.2.24 and a positive chloride reaction. Related substances are determined by liquid chromatography according to Ph. Eur. 2.2.29; the assay is expressed on the dried basis as 99.0–101.0%. Loss on drying is determined at 100–105 °C according to Ph. Eur. 2.2.32, with a typical limit of ≤ 0.5%. Sulfated ash is controlled according to Ph. Eur. 2.4.14, typically ≤ 0.1%. For injectable grade, bacterial endotoxins are tested according to Ph. Eur. 2.6.14 using a limit of 0.5 EU/mg or a tighter limit derived from the maximum adult dose per kilogram; sterility testing of the finished injection follows Ph. Eur. 2.6.1. Total aerobic microbial count is assessed under Ph. Eur. 2.6.12; non-sterile pharmaceutical substances are typically controlled at ≤ 100 CFU/g for bacteria and ≤ 10 CFU/g for combined yeasts and moulds.
| Parameter | Representative specification | Method reference |
|---|---|---|
| Appearance | White or almost white crystalline powder | Visual inspection |
| Identification | Infrared spectrum consistent with reference standard; positive chloride reaction | Ph. Eur. 2.2.24 |
| Assay on dried basis | 99.0–101.0% | Ph. Eur. 2.2.29 |
| Related substances | Monograph limits for specified, unspecified, and total impurities | Ph. Eur. 2.2.29 |
| Loss on drying | ≤ 0.5% | Ph. Eur. 2.2.32 |
| Sulfated ash | ≤ 0.1% | Ph. Eur. 2.4.14 |
| Residual solvents | Class 2 limits per ICH Q3C | Ph. Eur. 2.4.24 |
| Elemental impurities | Permitted daily exposure controls per ICH Q3D | Ph. Eur. 2.4.20 |
| Bacterial endotoxins, injectable grade | ≤ 0.5 EU/mg | Ph. Eur. 2.6.14 |
| Total aerobic microbial count | ≤ 100 CFU/g | Ph. Eur. 2.6.12 |
| Total yeasts and moulds | ≤ 10 CFU/g | Ph. Eur. 2.6.12 |
Because the API contains a dibrominated aromatic ring, liquid chromatographic methods with UV detection require system suitability checks for resolution between ambroxol and related debrominated or N-dealkylated impurities. The pharmacopoeial reference standard should be used to establish relative response factors; published response factor data for this specific impurity set are limited. Elemental impurity risk assessment follows ICH Q3D. Since the synthetic route does not rely on metal catalysis in the final step, the main elemental risks are residues from process equipment and water. The assessment typically evaluates lead, cadmium, mercury, and arsenic plus Class 2A elements such as cobalt, nickel, and vanadium. Injectable grades require parenteral permitted daily exposure limits, which are stricter than oral limits. Residual solvent control under ICH Q3C applies where methanol, dichloromethane, toluene, or other Class 2 solvents are used in recrystallization. Nitrosamine risk assessment is performed under current guidance; the dibrominated secondary amine structure is not a simple dialkyl secondary amine, and no N-nitrosamine specification is applied unless route-specific risk is identified.
Particle size distribution of the API influences content uniformity in direct compression, wet granulation, and capsule filling. Laser diffraction according to Ph. Eur. 2.9.31 is used to control D10, D50, and D90. A micronized grade may be supplied with D90 ≤ 20 µm; unmicronized material may exhibit D90 ≤ 150 µm, but these limits are not universal and must be taken from the certificate of analysis. In direct compression, the brittle crystalline hydrochloride is blended with microcrystalline cellulose, lactose monohydrate, crospovidone, and magnesium stearate. The API should be screened through a sieve of 0.5 mm aperture before blending to remove agglomerates. Blend uniformity is assessed according to Ph. Eur. 2.9.40 or USP 905; for low-dose tablets with active content below 5 mg, micronized grade is preferred to avoid concentration segregation. Flow is characterised by Carr index and Hausner ratio; a Carr index above 25% typically indicates that direct compression is unsuitable and granulation is required.
The API can be incorporated intragranularly in high-shear wet granulation using an aqueous binder solution. Granulation end point is determined by impeller torque and power consumption. Drying in a fluid-bed dryer should be conducted with product temperature below 40 °C unless forced degradation data support a higher limit; drying endpoint is controlled by loss on drying. Micronized material is produced by jet milling or pin milling; jet milling with compressed nitrogen reduces thermal input but can generate amorphous regions on crystal surfaces. Amorphous content can increase hygroscopicity and reduce chemical stability. The powder is therefore stored in double low-density polyethylene bags inside aluminium-laminated cartons with desiccant. If storage relative humidity exceeds 60%, pre-drying at 40 °C may be necessary before blending; specific drying time is determined by moisture isotherm data. Published data for ambroxol hydrochloride in this exact equipment configuration are limited, so these parameters are starting points rather than a validated design space.
Ambroxol hydrochloride injectable grade is supplied with reduced bioburden, low endotoxin, and sterile filtration compatibility. Injectable solutions are typically prepared at 7.5 mg/mL or 15 mg/mL in water for injections, with sodium chloride as tonicity agent and pH adjustment with hydrochloric acid or sodium hydroxide to 4.0–5.5. The hydrochloride salt contributes weakly acidic behaviour; pH adjustment must be performed with stirring to avoid local pH extremes. Terminal sterilization by moist heat at 121 °C for 15 minutes is used only if the specific solution formulation is validated for the full cycle; amber glass or opaque secondary packaging is required because the dibrominated arylamine chromophore is light-sensitive. Nitrogen blanketing during filling may be applied to reduce oxidative degradation. Finished product testing includes sterility according to Ph. Eur. 2.6.1, bacterial endotoxins according to Ph. Eur. 2.6.14, particulate matter according to Ph. Eur. 2.9.19, and assay by liquid chromatography. The injectable API grade is not interchangeable with unmicronized oral grade because bioburden and endotoxin limits differ.
The API should be dissolved in water for injections at 15–30 °C; dissolution temperatures above 40 °C can accelerate oxidative degradation. The solution is filtered through 0.45 µm and 0.22 µm sterilising filters; filter compatibility should be tested because the dibrominated molecule may adsorb to nylon membranes. Polyethersulfone or polyvinylidene fluoride membranes are typically evaluated. If headspace oxygen reduction is applied, oxygen content below 2% v/v is often targeted where oxidative degradation is observed. An alternative moist-heat cycle of 115 °C for 30 minutes can be considered for heat-sensitive formulations, but the qualified cycle must be linked to stability and impurity data.
For tablets and capsules, the API is incorporated either by direct compression, dry granulation, or wet granulation. Direct compression is limited by flow and segregation, not by chemical stability. Unmicronized material can be roller-compacted with microcrystalline cellulose and crospovidone to form granules. Ribbon density is monitored by stereopycnometry after compaction; if ribbon density is outside the target range, granule porosity and tablet tensile strength vary. A compaction force starting range of 5–15 kN/cm is often evaluated on pilot-scale roller compactors, but the qualified range must be established with batch size and roll geometry fixed. Milling through a 1.0–1.5 mm rotor screen yields granules for encapsulation or tablet compression. Lubrication with magnesium stearate at 0.5–1.0 wt% is typical; over-lubrication is detected as a tensile strength loss greater than 20% relative to unlubricated blend. Capsule filling on dosator machines may require granules with Carr index below 20%.
Formulation differences from other mucolytic actives are measurable. Unlike N-acetylcysteine, which contains a free thiol group and requires chelating agents and nitrogen blanketing in aqueous injection, ambroxol hydrochloride does not contain a free sulfhydryl group. Bromhexine hydrochloride is a prodrug that requires hepatic conversion to ambroxol; the direct use of ambroxol hydrochloride removes that metabolic step. Carbocisteine has a different acid/base profile and does not contain the same dibrominated aromatic system. In oral granules, the absence of a free thiol reduces sulfurous odour and simplifies taste-masking compared with acetylcysteine. Injectable ambroxol hydrochloride does not require edetate disodium as a metal chelator, although pH control and light protection remain critical.
| Property | Ambroxol HCl | Bromhexine HCl | N-Acetylcysteine |
|---|---|---|---|
| CAS registry number | 23828-92-4 | 611-75-6 | 616-91-1 |
| Relative molecular mass | 414.56 g/mol | 412.60 g/mol | 163.20 g/mol |
| Free thiol group | Absent | Absent | Present |
| Aqueous injection stability requirements | pH control and light protection | pH control and light protection | Metal chelation, nitrogen blanketing, and pH control |
| Primary route | Active mucolytic | Prodrug converted to ambroxol | Disulfide-reducing mucolytic |
Direct compression with the micronized API requires controlling segregation and lubrication. Because the micronized powder has a high specific surface area, it may exhibit poor flow and low bulk density. Preconditioning by dry sieving or pre-compaction can be used. Compression force is optimised with a rotary tablet press; for a 10 mm round flat-faced tooling, main compression force is typically evaluated from 6 kN to 14 kN. The exact range is dependent on tablet weight and excipient grade. Tablets are tested for hardness, friability according to Ph. Eur. 2.9.7, disintegration according to Ph. Eur. 2.9.1, and dissolution according to a pharmacopoeial validated method. If friability exceeds 1.0%, the compaction force or binder concentration is adjusted. For capsules, powder or granules are filled to target fill weight with a dosing disc or tamping pin capsule filler; fill weight variability is controlled to ± 3% for low-dose products.
Roller compaction is used when dry granulation is required. The blend is compacted into ribbons using a roll gap of 1–3 mm, roll speed 2–10 rpm, and hydraulic pressure adjusted to achieve ribbon density 0.85–1.15 g/cm³; these are pilot-scale starting ranges and must be confirmed. The ribbons are milled through a mill screen of 1.0 mm or 1.25 mm; granule size distribution is assessed by sieve analysis according to Ph. Eur. 2.9.38 or USP 786. Recompression of granules with extragranular disintegrant and lubricant is followed by tablet compression. Near-infrared reflectance spectroscopy can monitor granule moisture and blend uniformity; method validation follows ICH Q2(R1). Published data for ambroxol hydrochloride in this exact configuration are limited, so the design space must be established by factorial studies and hold-time studies should include sampling at 0 h, 24 h, 48 h, and 72 h to detect redistribution of magnesium stearate or moisture uptake.
When a dry syrup or granule dosage form is required, fluid-bed top-spray granulation is used. Binder solution is sprayed at a rate that maintains product temperature below 35 °C; inlet air humidity is controlled to avoid over-wetting. The dried granules are sized through a sieve with aperture 1.4 mm and filled into sachets. Loss on drying is controlled to 1.0–2.0% for stability. The granule base typically contains sucrose or sorbitol, sodium cyclamate, and flavouring; the API is preblended with a colorant to ensure visual homogeneity. The oral granule grade differs from the injectable grade in particle size, bioburden, and endotoxin control. If taste masking is required, the selected coating polymer must not contain aldehyde groups that can react with the secondary amine.
