revealed that due to drug-drug interaction, hepatotoxicity was 14.88% for combina-

tion of acetaminophen-omeprazole, 17.15% for combination of acetaminophen-

rifampicin, and 19.74% for acetaminophen when taken with ciprofloxacin. It showed

that this 3D printed liver model can be used to analyse hepatotoxicity of newly

discovered drug and drug-drug interactions (Deng et al. 2019). In another study, the

renal proximal tubule was bio-printed to analyse the nephrotoxicity of cyclosporine

A in place of preclinical studies. This bio-printed proximal tubule was proved to be

useful for testing of newly discovered drugs and in vitro disease modelling (Homan

et al. 2016).

Biglari et al. during a study developed a skin ‘wound-on-chip’ model to analyse

the anti-inflammatory efficacy of dexamethasone and macrophages during wound

healing. The researchers were able to predict the mechanism of wound healing

process of macrophages and dexamethasone. This 3D ‘bio-printed model’ can

provide insight into the mode of action of a newly discovered drug/new drug

substance for tissue regeneration and can improve preclinical models, according to

the scientists (Biglari et al. 2018).

The studies in literature reveal that the 3D printed ‘organ-on-a-chip’ is a micro-

scale device that mimics the human body’s environment. One of the main goals of

organ-on-a-chip is to develop human tissue models for disease modelling and drug

research. Microfluidics and cells are used to create physiological and mechanical

conditions like those found in the human body. Various types of ‘organs-on-a-chip’

are depicted in Fig. 6.3, and their development procedures and uses are discussed in

greater detail further down.

Fig. 6.3 Types of organ-on-a-chip

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