Abstract

     Wastewater from pharmaceutical industries contains different antibiotics and other effluents that directly affect the environment. For the degradation of antibiotics, nanotechnology is an emerging field in research that majorly focuses on molecules and atoms. Nanoparticles are fine micro-particles with more than one dimension from a size of 1–۱۰۰ nm. The synthesized nanoparticles can directly be used for the process of degradation of antibiotics in wastewater. Titanium dioxide nanoparticles are majorly used among nanoparticles due to their small surface area and particle size. There are various physical, chemical and conventional (biological) methods for synthesizing titanium dioxide nanoparticles. Green synthesis is an environmentally friendly, less expensive and harmless approach, and these methods are much more efficient than any other physical-chemical means. Titanium dioxide nanoparticles are used for different purposes. In food products, these nanoparticles act as photocatalysts and are also used as a coating material in food packaging. Electrochemical biosensors are combined with titanium dioxide nanoparticles for developing nano sheet matrices. Furthermore, this review describes the usage of biological components (plants, microorganisms like fungi and bacteria) to synthesize titanium dioxide nanoparticles. The present review also focuses on applying synthesized titanium dioxide nanoparticles in various drug delivery systems and other bioactivities.

Introduction

     Water is one of the important components of life used in the domestic, industrial, and agricultural sectors. The increase in consumption leads to an increase in the toxicity of pollutants inside water. The concentrations of emerging pollutants like pharmaceutical compounds have increased [1]. Various types of pharmaceutical compounds are observed in the aqueous environment, including antibiotics. These compounds reach the aquatic habitat through hospital effluents, the pharmaceutical industry and human livestock. The consumption of antibiotics has increased, and the concentration increases inside the aquatic environment, leading to the development of antibiotic-resistant bacteria [2,3].

     To remove antibiotics from wastewater, the traditional sewage treatment method is not appropriate and is not much effective in removing the residuals of antibiotics. Nanoparticles can be used as a photocatalyst for the degradation of antibiotics and other organic pollutants [4]. Nanotechnology is defined as synthesizing and developing various nanomaterials by manipulating the matter at the nanoscale [5]. Nanomaterials are a bridge between molecular material and bulk material. They have a size range of 1–۱۰۰ nm due to their different shapes, sizes, large surface area, and possess high reactivity [6]. This has become an emerging field in science in the last few years due to its wide range of applications [7]. Because of its small size, the effect can be seen in the physical, optical, chemical properties, melting point, and dielectric constant of various nanoparticles [8].

Conclusion

     The interest in green synthesis is due to its advantages of being innocuous to the environment. Different parts of plants are used for synthesis purposes, and their characterization using various techniques helps form TiO2 NPs of varied shapes and sizes. The green synthesis of TiO2 NPs can be used in biomedical, and the delivery of drugs and antibiotics in wastewater of pharmaceutical industries can be degraded using nanoparticles. Because of the less use of precursors, TiO2 is widely used to remove microbes from water surfaces. The nanoparticles inhibit the growth of microbes and are used in wound dressing. Moreover, nanoparticles synthesized using the green routes are more effective than chemical or physical means.