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To develop biopolymers for packaging materials, various biopolymers, biosynthetic polymers, chemosynthetic polymers, their blends, and composites have been studying for the last 2 decades. Natural polysaccharides are one of the most available and cheap materials found in nature. Here, a biopolymer film based on a natural polysaccharide, particularly potato starch, is utilized to establish a facile approach to fabricate starch–clay nanocomposite (SC–NC) film, which may potentially be used as an alternative to synthetic plastics. A range of plasticizers and a family of 2:1 phyllosilicates smectic clay, hectorite, are used to prepare the film through a very simple casting method. The clay particles are found to be homogeneously dispersed in SC–NC film at an optimum clay concentration. The mechanical properties of SC–NC film are significantly improved, and the degree of crystallinity is decreased with increasing concentration of clay to indicate the superior biodegradability of the films. The SC–NC film exhibits better thermal features compared with an ordinary starch film. The swelling percentage of SC–NC film is also greatly decreased to be used as a packaging film.

Efficient purification is crucial to providing large quantities of recombinant therapeutic proteins, such as monoclonal antibodies and cytokines. However, affinity techniques for manufacturing protein therapeutics that use biomolecule-conjugated agarose beads that harness specific biomolecular interactions suffer from issues related to protein denaturation, contamination and the need to maintain biomolecule-specific conditions for efficient protein capture. Here, we report a versatile and scalable method for the purification of recombinant protein therapeutics. The method exploits the high-affinity and controllable host–guest interactions between cucurbit[7]uril (CB[7]) and selected guests such as adamantylammonium. We show that the Herceptin (the brand name of trastuzumab, a monoclonal antibody drug used to treat breast cancer) and the much smaller cytokine interferon α-2a can be purified by site-specifically tagging them with adamantylammonium using the enzyme sortase A, followed by high-affinity binding with CB[7]-conjugated agarose beads and the recovery of the protein using a guest with a stronger affinity for CB[7]. The thermal and chemical stability of CB[7] beads and their scalability, recyclability and low cost may also make them advantageous for the manufacturing of biosimilars. The high-affinity and controllable host–guest interactions between cucurbit[7]uril and selected guests enables a versatile and scalable method for the purification of recombinant protein therapeutics.

Due to the rapid spread of the novel coronavirus disease-2019 (COVID-19), cases in Bangladesh have continued to increase with a total number of confirmed cases of over 1.04 million and over 16,842 deaths (as of July 14, 2021). Such a surge in COVID-19 cases has caused detrimental impacts in all areas of human lives including students of all levels. The economic and psychological costs to students in higher learning institutions in Bangladesh are believed to be very high compared to other demographic groups in the country (Islam et al., 2020) as a large proportion of expenditure (29% of total education cost) is spent on private tutoring (Toaha, 2015). All the educational institutions in Bangladesh were (physically) closed since early March 2020 and will continue to be so until August 2021 (Ela et al., 2021; Xinhua, 2021).