Nanotechnology and Biomedicine: Applications and Reviews

Three Ways Nanotechnology Can Be Used to Treat Diabetes

What are three ways nanotechnology can be used to treat diabetes?

How could nanoencapsulation be used to deliver drugs across the blood-brain barrier?

How can nanotechnology be used to stimulate nerve growth?

Briefly, what is biomimetics and what is bionics?  A few examples with nanotechnology?

How can nanotechnology be used to prevent artificial bone implants from being rejected by the body?

Compare and contrast electrospinning and electrospraying.

What is surface plasmon resonance?

Contrast localized injection of nanoparticles vs intravenous injection of nanoparticles for in vivo anticancer therapy.

What are the (biological) dangers of free radicals?

Nanotube antioxidants:  (a) How do nanotubes soak up free radicals, (b) explain how nanotubes can generate free radicals.

Describe how Pluronic P85 drives the delivery of drugs across the blood-brain barrier.

Why is hydroxyapatite the ceramic of choice for biomedical implants?

Why are collagen nanofibers so popular in the area of 3D cell culture?

How can buckyballs be made water soluble?

What is the difference between a tumor-associated antigen and a tumor-specific antigen?

What are the advantages of SERS over fluorescence signals in diagnostics?

How do Dmitri Lapotko’s plasmonic nanobubbles both diagnose and eradicate cancer cells?

Suppose cancer cell division has a geometric growth rate with time, where the number of cells doubles every six days. If cancer starts as one cell, how many cancer cells would you expect after four months. If each cancer cell is 50 microns in diameter, how big is the tumor at four months?  Could this be detected using MRI with 0.5 cm resolution?

Why will nanoparticles not settle to the ground?  Explain in terms of the physical and chemical forces on nanoparticles.

Doubling the diameter of a cell means that a given molecule, when introduced into a cell, will take _____ times longer to be found at any other locating in the cell’s volume.

If a molecule has a diffusion coefficient of D = 4 x 10-5 cm2s-1 what will be its mixing time in a cell of diameter 1 micron (such as a bacteria), or a cell of 10 microns (such as a human cell)?

Given the mass of colloidal silica particles per cubic meter of air is 100 micrograms, a particle density of 2 g/cm3 (= 2 x 106 g/m3), and an average particle size (diameter) of 100 nm, what is the number of particles per m3 of air? What is the total surface area (m2) of the particles?

Nanoencapsulation for Delivering Drugs Across the Blood-Brain Barrier

Because of their much higher delivery efficiency, a much smaller mass of drug-laden liposomes can be used to do the same job as a much larger mass of conventional pain reliever.  If five billion 10-nm liposomes can match the pain-relieving effect of a 325-mg pill of pain reliever, how much more efficient are liposomes to conventional pills (ratio of drug in liposome to pill, for same effect)? The density of the drug is 1250 kg/m3.  (See ROGERS, Back of Envelope calculation 11.1).

“A size exclusion nanocellulose filter paper for virus removal”  Advanced Healthcare Materials (2014) 3 1546-1550.

What are some applications or needs for viral removal?

What are some of the current methods for removing viruses?

What are the advantages of filtration for removing viruses?

Presumably, most applications need a filter paper that traps viruses but allows proteins to pass:  How does this translate to desired pore size?

For filtering, in addition to pore size, how else might selectivity be achieved for viruses?

How is the distribution of pore size measured?

What is the natural source of the cellulose used here?

How was the size exclusion characteristics of the nano filter paper measured?

H YUE et al. “Advances in clustered, regularly interspaced short palindromic repeats (CRISPR)-based diagnostic assays assisted by Micro/Nanotechnologies” ACS Nano (2021) 15 7848-7859.

Note: Since you are biotech students, you already or should know about CRISPR.  Here we look at CRISP for diagnostics rather than gene editing, and how nanotechnology can foster applications, particular for point-of-care (POC) diagnostics.

What makes CRISPR systems more specific than PCR? (not explicitly described in article), and why is CRSIPR cleavage (and detection of such cleavage) diagnostic for a biomarker?

Briefly, how can AuNPs be used to enhanced detection of CRISPR cleavage?

Why advantages do AuNPS for detection have over fluorescence detection?

How is the catalytic activity of Pt nanoparticles used in CRISPR DNA diagnostics?

Why is nucleic acid detection challenging or limited with LFAs?  And how can CRISPR systems address these issues?

The SERS detection on p 7852 claims femtomolar detection. Assuming the sample volume is 100 microliters, how many molecules (copies) of target DNA does this correspond to (as an LOD, limit of detection).  How does this compare with PCR LOD?   Why might detection without amplification (as with PCR) be an attractive alternative for POC diagnostics?

Although CRSIPR is essentially a nucleic acids technology, how can it be extended for non-nucleic acid detection?

“Spherical nucleic acids: Integrating nanotechnology concepts into general chemistry curricula” J Chemical Education (2021) 98 3090-3099.

Note: Chemistry is about atoms, molecules, bonds, bonding (reactions) and bond types, valency, structure, and properties.  This interesting article in the J Chemical Education discusses using nanostructures to recapitulate ‘chemistry’ at a different scale. 

In nanometers, what are typical sizes of atoms, small molecules, and macromolecules? And what are the sizes of the some of the ‘nanoatom’ structures described here?

How can valency and directed bonds be simulated by SNAs?

Compare how salt crystals form from sodium and chloride ions, and how PAEs (or SNAs) can form analogous structures.

How can different crystal structures be self-assembled from PAEs?

Unlike bonding between atoms to form molecules, how can bonds length, strength, and multiplicity of bonds be controlled with more latitude in PAE structures (‘molecules’ or ‘crystals’)?

How can the melting temperature of SNA assemblies be measured?; compare with linear nucleic acids.

In this context, What information do phase diagrams convey?

What are some interesting features of SNAs for biomedical applications?

J Liu et al. “Renal clearable inorganic nanoparticles: A new frontier of bionanotechnology”  Materials Today 16,12 (20130 477-486.

What are some reasons nanoparticles are injected into patients?

Why is kidney filtration of nanoparticles important, and what are some of the criteria that determine the effectiveness of kidney filtration for particles?

What are some approaches to enhancing or assuring adequate kidney clearance of nanoparticles?

Briefly, what are some methods to assess the fate and clearance of nanoparticles in animals?

Briefly discuss the inter-relationships between fast or slow clearance, and passive and active tumor targeting.