Continuous Manufacturing of Cocrystals Using 3D-Printed Microfluidic Chips Coupled with Spray Coating

Using cocrystals has emerged as a promising strategy to improve the physicochemical properties of active pharmaceutical ingredients (APIs) by forming a new crystalline phase from two or more components. Particle size and morphology control are key quality attributes for cocrystal medicinal products. The needle-shaped morphology is often considered high-risk and complex in the manufacture of solid dosage forms. Cocrystal particle engineering requires advanced methodologies to ensure high-purity cocrystals with improved solubility and bioavailability and with optimal crystal habit for industrial manufacturing. In this study, 3D-printed microfluidic chips were used to control the cocrystal habit and polymorphism of the sulfadimidine (SDM): 4-aminosalicylic acid (4ASA) cocrystal. The addition of PVP in the aqueous phase during mixing resulted in a high-purity cocrystal (with no traces of the individual components), while it also inhibited the growth of needle-shaped crystals. When mixtures were prepared at the macroscale, PVP was not able to control the crystal habit and impurities of individual mixture components remained, indicating that the microfluidic device allowed for a more homogenous and rapid mixing process controlled by the flow rate and the high surface-to-volume ratios of the microchannels. Continuous manufacturing of SDM:4ASA cocrystals coated on beads was successfully implemented when the microfluidic chip was connected in line to a fluidized bed, allowing cocrystal formulation generation by mixing, coating, and drying in a single step.

Effects of piroxicam on tissue distribution of sulfadimidine in West African Dwarf male and female goats

Cases of Stevens-Johnson syndrome have been increasingly reported in Nigeria by individuals who consumed meat products of animals especially goats injected sulfonamides. Hence, tissue distribution and residues of intramuscular sulfadimidine were studied in West African Dwarf (WAD) goats. Twenty goats divided into two groups of 10 each (five males; five females) weighing 10.4 ± 1.63 kg were administered intramuscular sulfadimidine (100 mg/kg body weight), and the second group was coadministered 5 mg/kg of piroxicam via right and left thigh muscle, respectively. Samples of the liver, kidney, spleen, heart, lung, intestine, brain, and skeletal muscle were collected into sterile cellophane bags. Two untreated goats were killed and used for preparation of tissue standards. The tissue samples were stored frozen for analysis. High concentration of sulfadimidine residues was found in all the tissues of goats administered sulfadimidine as well as tissues of goats coadministered sulfadimidine/piroxicam for up to 30 days postdrug administration. Generally, residues of sulfadimidine were observed to be significantly higher than the acceptable limit (0.1 ppm). Hence, consumption of meats from WAD goats administered sulfadimidine may pose very high risk of Stevens-Johnson syndrome in sensitive humans. As such consumption of such meats should be avoided.

Oral absorption profiles of sulfonamides in Shiba goats: a comparison among sulfadimidine, sulfadiazine and sulfanilamide

The oral pharmacokinetics of three sulfonamides, sulfadimidine (pKa 7.5), sulfadiazine (pKa 6.5) and sulfanilamide (pKa 10.5), with different rates of unionization in rumen juice, were compared in Shiba goats to clarify the relationship between drug absorption profiles after their oral administration as well as their degree of unionization in the rumen. Sulfonamides were administered either into the left jugular vein or orally to five male goats at doses of 10 mg/kg body weight, using a crossover design with at least a 3-week washout period. The Tmax of sulfadimidine, sulfadiazine and sulfanilamide reached 2.0 ± 1.2, 6.0 ± 0.0, and 7.8 ± 1.6 hr, respectively, after their oral administration, and this was followed by their slow elimination due to a slow rate of drug absorption from the gastrointestinal tract. The MAT and t1/2ka of sulfadiazine (13.2 ± 2.0 and 10.9 ± 1.08 hr) were significantly longer than those of sulfanilamide (9.09 ± 1.67 and 7.46 ± 1.70 hr) and sulfadimidine (7.52 ± 0.85 and 5.17 ± 0.66 hr). These results suggest that the absorption rates of highly unionized drugs (such as sulfanilamide and sulfadimidine) from the forestomach of goats may be markedly higher than less unionized ones (such as sulfadiazine). The mean oral bioavailability of sulfadiazine was high (83.9 ± 17.0%), whereas those of sulfadimidine and sulfanilamide were low (44.9 ± 16.4% and 49.2 ± 2.11%, respectively).