Introduction: Although there have been significant contributions from the pharmaceutical industry to clinical practice, several diseases remain unconquered, with the discovery of new drugs remaining a paramount objective. The actual process of drug discovery involves many steps including pre-clinical and clinical testing, which are highly time- and resource-consuming, driving researchers to look for technological interventions that can improve the process efficiency. The shift of modelling technology from two-dimensions (2D) to three-dimensions (3D) for in vitro drug screening is one of such advancements. Three-dimensional models allow for close mimicry of cellular interactions and tissue microenvironments thereby improving the accuracy of results. The advent of this bioprinting technology for fabrication of tissue constructs has shown potential to improve 3D culture models. Areas covered: The present review provides a comprehensive update on a wide range of bioprinted tissue models and appraise them for their potential use in drug discovery research. Expert opinion: Efficiency, reproducibility, and standardization are some impediments of the bioprinted 3D models. In addition, vascularization of the constructs has to be addressed for the bioprinting domain, in the near future. While much progress has already been made with several seminal works, the next milestone will be the commercialization of these models after due regulatory approval.

In the biomedical field, the use of fluorescence imaging in the second near‐infrared (NIR‐II) region is growing rapidly because it imparts the advantages of reduced autofluorescence and low photon scattering. The advantage of reduced scattering is that it increases penetration depth in vivo and improves imaging clarity. Herein, this work uses mesoporous silica, a biocompatible template that can be easily modified, functionalized, and loaded with drugs for use in several bioapplications. The ZnGa2O4 spinel oxide system is integrated into mesoporous silica and different concentrations of Cr3+ and Ni2+ are loaded in octahedral sites to obtain the highest emission intensity in the NIR‐II region at 1285 nm via energy transfer from Cr3+ to Ni2+. Given that only a few nanophosphor systems with emission in the NIR‐II region are available, this work attempts to establish emission in the NIR‐II and NIR‐I regions to obtain images in vivo with an increased penetration depth to 5 mm and improved clarity for bioimaging purposes. This system will open the door for biomedical research on other NIR‐II nanophosphors.

No abstract

The most common malignant tumor of the brain is glioblastoma multiforme (GBM) in adults. Many patients die shortly after diagnosis, and only 6% of patients survive more than 5 years. Moreover, the current average survival of malignant brain tumors is only about 15 months, and the recurrence rate within 2 years is almost 100%. Brain diseases are complicated to treat. The reason for this is that drugs are challenging to deliver to the brain because there is a blood–brain barrier (BBB) protection mechanism in the brain, which only allows water, oxygen, and blood sugar to enter the brain through blood vessels. Other chemicals cannot enter the brain due to their large size or are considered harmful substances. As a result, the efficacy of drugs for treating brain diseases is only about 30%, which cannot satisfy treatment expectations. Therefore, researchers have designed many types of nanoparticles and nanocomposites to fight against the most common malignant tumors in the brain, and they have been successful in animal experiments. This review will discuss the application of various nanocomposites in diagnosing and treating GBM. The topics include (1) the efficient and long-term tracking of brain images (magnetic resonance imaging, MRI, and near-infrared light (NIR)); (2) breaking through BBB for drug delivery; and (3) natural and chemical drugs equipped with nanomaterials. These multifunctional nanoparticles can overcome current difficulties and achieve progressive GBM treatment and diagnosis results.