THROMBOLIN GEL Pharma Grade API for Tablet / Capsule / Granule / Injection, Oral & Injectable is supplied under the manufacturer’s grade designation TGL-PG-API-OI/01 as a white to pale-yellow crystalline powder. The material is intended for dual use in solid oral dosage forms and in injectable products where the same API can be processed by terminal sterilisation or aseptic filling. The compendial control strategy follows ICH Q6A decision tree #4 for particle size and dissolution, ICH Q3C for residual solvents, and ICH Q3A for organic impurities. For solid-dose formulation, the powder is first passed through a 500 µm security screen and sampled for loss on drying, particle size distribution, and tap density before it is released to weighing. Published data for this specific configuration is limited; therefore, release criteria are stated as compendial alignment limits rather than clinical bioequivalence limits.

Specifications and Release Criteria for Tablet, Capsule, and Granule Processing

Particle size distribution is determined by laser diffraction in accordance with USP <429> and Ph. Eur. 2.9.31. The standard oral grade is specified with D90 ≤ 100 µm and D50 between 15 µm and 45 µm; the injectable-micronised grade is specified with D90 ≤ 10 µm. For tablet and capsule processing, the coarser grade reduces segregation but may produce slower dissolution in low-solubility media. Loss on drying by Ph. Eur. 2.2.32 is controlled at ≤ 0.50% w/w after drying at 105 °C to constant weight, and residue on ignition is ≤ 0.10% w/w. Heavy metal limits by USP <232> are set at ≤ 10 ppm lead, ≤ 5 ppm cadmium, ≤ 5 ppm arsenic, and ≤ 2 ppm mercury. Residual solvent limits by headspace GC under USP <467> are aligned with ICH Q3C Option 2: methanol ≤ 3000 ppm, dichloromethane ≤ 600 ppm, and toluene ≤ 890 ppm. Powder flow metrics reported on the certificate of analysis include bulk density from 0.28 g/mL to 0.40 g/mL, tapped density from 0.42 g/mL to 0.55 g/mL, and Carr index from 18% to 25% before addition of glidant. These values are not absolute specifications but serve as formulation engineering references for direct compression, wet granulation, and capsule filling.

During high-shear wet granulation, the API is dispersed in a binder solution composed of 5% w/w povidone K30 and 2% w/w pregelatinised starch before transfer to a 12-bar fluid-bed granulator. The inlet air temperature is set to 60 °C ± 5 °C, and the endpoint is controlled by near-infrared moisture at 1.5% to 2.5% w/w or by impeller torque increase. Tablets are compressed on a 16-station rotary press with 10 mm round tooling using 2 kN to 4 kN precompression force and a main compression force sufficient to achieve 15 kP to 25 kP tablet hardness. For capsule filling, relative humidity is maintained below 40% RH because the powder becomes cohesive above this threshold; dosator plug weight variability on a 60 mm powder bed rises when the moisture exceeds 0.50% w/w. Dissolution is monitored by USP <711> Apparatus II at 50 rpm in 900 mL of 0.1 N HCl. A processing conflict occurs when the particle size is reduced to improve dissolution: micronised material with D90 ≤ 10 µm can increase the Carr index relative to the coarser grade, requiring 1.0% w/w colloidal silicon dioxide and 0.5% w/w sodium stearyl fumarate to restore flow. The latter is preferred over magnesium stearate when dissolution sensitivity to hydrophobic lubricant films is observed.

When THROMBOLIN GEL Pharma Grade API Is Used for Injectable Dosage Forms

In terminal sterilisation of the micronised grade, the API is first dissolved in Water for Injection after pH adjustment to 4.0 to 5.5 with citric acid or acetate buffer; if oxidation is a concern, nitrogen overlay and 0.02% w/v ascorbic acid may be used. The solution is filtered first through a 0.45 µm polyethersulfone prefilter and then through a sterilising 0.22 µm PVDF membrane. For terminally sterilised products, a cycles of 121 °C for 15 minutes is acceptable where stability studies demonstrate no degradation beyond ICH Q1A limits; if the API is heat-labile in a specific formulation, aseptic processing with sterile filtration is employed under 21 CFR 211.113 controls. Sub-visible particulate matter is controlled by USP <788> / Ph. Eur. 2.9.19: no more than 3000 particles per container at ≥ 10 µm and no more than 300 particles per container at ≥ 25 µm for small-volume injections. Bacterial endotoxin control at < 0.10 EU/mg API translates to a formulation-level limit consistent with USP <85>; the limit per dose is calculated from the maximum bolus dose and must not exceed 5 EU/kg body weight per hour for intravenous administration. The main operational boundary is that micronised API should not be exposed to relative humidity above 30% RH during aseptic weighing because adsorbed moisture facilitates particle bridging in the filter train and can increase filter differential pressure beyond 0.5 bar.

What Limits the Substitution of Technical-Grade Material in Oral or Injectable Manufacturing?

The pharma-grade product is differentiated from technical-grade thrombolin gel by purity, low bioburden, controlled residual solvents, and particle-size consistency. HPLC purity by USP <621> is specified at ≥ 99.0% anhydrous substance, with unspecified impurities limited to ≤ 0.10% according to ICH Q3A. Technical-grade material, by contrast, may have a purity of 96.0% to 98.5% and an endotoxin load above 5.0 EU/mg. The pharma grade is milled under an ISO 8 controlled environment and passed through a 650 µm security sieve with a rare-earth magnet trap; the technical grade is not typically subjected to the same foreign-particle control. Residual solvent content differs mainly in toluene and dichloromethane, where technical lots may exceed 1500 ppm and 1200 ppm respectively. The oral-injectable grade also has a tighter particle-size distribution: D10 ≥ 5 µm, D50 15 µm to 45 µm, and D90 ≤ 100 µm for the standard oral material, whereas technical material can show a bimodal distribution with oversize aggregates above 200 µm. These differences affect direct-compression content uniformity: a formulation containing technical-grade powder at 20% w/w drug load may require longer blending times, but this is not recommended because of dissolution sensitivity to lubricant overmix.

For granule production, the API is coated onto sugar spheres in a Wurster column; the spray rate is kept at 8 g/min to 12 g/min and atomising air pressure at 1.2 bar to 1.8 bar to avoid agglomeration. Fluid-bed top spray may be used for taste-masked granules with ethylcellulose at 10% w/w coating level. Granule size is controlled between 250 µm and 710 µm by sieve analysis under USP <786>. Liquid oral formulations are prepared by dissolving the API in a vehicle of purified water, sorbitol, and citrate buffer at pH 4.0 to 5.5. A preservative system of methylparaben 0.18% w/w and propylparaben 0.02% w/w is used in multidose bottles; benzalkonium chloride is avoided because of precipitation risk with anionic buffers. The solution is protected from light and stored in amber glass at 15 °C to 25 °C. Chemical stability under ICH Q1A is assessed at 40 °C / 75% RH for 6 months and 25 °C / 60% RH for 12 months. Incompatibility is noted with strong oxidising agents, reducing sugars, and amine-based buffering agents at alkaline pH, which accelerate degradation. Published data for this specific configuration is limited in the open literature; formulation decisions should therefore be driven by forced-degradation studies under ICH Q1B and ICH Q2(R1) validated HPLC methodology.