3D-Printed Tumor-on-Chip for the Culture of Colorectal Cancer Microspheres: Mass Transport Characterization and Anti-Cancer Drug Assays.

Tumor-on-chips have become an effective resource in cancer research. However, their widespread use remains limited due to issues related to their practicality in fabrication and use. To address some of these limitations, we introduce a 3D-printed chip, which is large enough to host ~1 cm3 of tissue and fosters well-mixed conditions in the liquid niche, while still enabling the formation of the concentration profiles that occur in real tissues due to diffusive transport. We compared the mass transport performance in its rhomboidal culture chamber when empty, when filled with GelMA/alginate hydrogel microbeads, or when occupied with a monolithic piece of hydrogel with a central channel, allowing communication between the inlet and outlet. We show that our chip filled with hydrogel microspheres in the culture chamber promotes adequate mixing and enhanced distribution of culture media. In proof-of-concept pharmacological assays, we biofabricated hydrogel microspheres containing embedded Caco2 cells, which developed into microtumors. Microtumors cultured in the device developed throughout the 10-day culture showing >75% of viability. Microtumors subjected to 5-fluorouracil treatment displayed <20% cell survival and lower VEGF-A and E-cadherin expression than untreated controls. Overall, our tumor-on-chip device proved suitable for studying cancer biology and performing drug response assays.

Comparative In-Vitro Quality Control Testing of Different Brands of Paracetamol Tablets Available In The Trinidad & Tobago, West Indies

Paracetamol tablets are popular over the counter (OTC products among the patients as a good analgesics and antipyretics. The objective of this study was to compare the quality of the paracetamol tablet formulations those are locally available in Trinidad & Tobago pharmaceutical market manufactured by various pharmaceutical companies with pharmacopoeia standards. The four popular brands (A, B, C, D) of paracetamol conventional tablet of 500 mg strength were chosen. The paracetamol tablets were obtained from government hospital pharmacies as well as from local private pharmacies. To compare the quality of tablet formulations of different brands various official parameters like friability, weight variation, disintegration time, dissolution and drug assay tests were performed as per the pharmacopoeia. The result of all these parameters of different brands were in the pharmacopoeial limits so it could be concluded that marketed pharmaceutical tablets of paracetamol of these brands are safe, effective and efficacious as well as satisfy quality control limits of pharmacopoeia.