The development of antibiotics has played a significant role in combating the dreaded infectious disease such as tuberculosis, pneumonia, typhoid fever and meningitis in 20th century. However, the improper use of antibiotics led to the development of multidrug resistance (MDR) in microbial flora raising a global public health concern of 21st century. This unforeseen threat demands the development of new drugs and strategies for combating antibiotic resistance shown by many microbial species. Recent developments in nanotechnology to engineer nanoparticles with desired physicochemical properties have been projected as a new line of defense against MDR micro-organism. In this review, we summarized and discussed the recent development demonstrating the potential of nanomaterials to evade the MDR. Nanoparticles have shown effective antimicrobial activity against MDR bacteria, such as Acinetobacter baumanii, Pseudomonas aeruginosa, Klebsiella pneumoniae, Mycobacterium tuberculosis, vancomycin resistant enterococci, methicillin-resistant Staphylococcus aureus and others. Furthermore, new strategies like combination of radiation and drugs with nanoparticle that are being explored to potentiate the effectiveness against MDR bacteria have also been summarized.

Cholesterol oxidase (ChOx) has been immobilized onto zinc oxide (ZnO) nanoporous thin films grown on gold surface. A preferred $c$ -axis oriented ZnO thin film with porous surface morphology has been fabricated by rf sputtering under high pressure. Optical studies and cyclic voltammetric measurements show that the $\mathrm{ChOx}∕\mathrm{Zn}\mathrm{O}∕\mathrm{Au}$ bioelectrode is sensitive to the detection of cholesterol in $25–400\mathrm{mg}∕\mathrm{dl}$ range. A relatively low value of enzyme’s kinetic parameter (Michaelis-Menten constant) $\sim 2.1\mathrm{mM}$ indicates enhanced enzyme affinity of ChOx to cholesterol. The observed results show promising application of nanoporous ZnO thin film for biosensing application without any functionalization.