Author Archives: vivian hou zhang

Coloured Contact Lenses: Do They Bring More Harm than Good?

Are you thinking about wearing coloured contact lenses to change the colour of your eyes? While it may appear to be a simple and risk-free way to enhance your natural eye colour or make a fashion statement, it is critical to consider the chemical composition as well as the potential risks associated with these lenses. Let’s look at the chemistry of coloured contact lenses and weigh the upsides and downsides.

Better Vision different colour contact lenses. Source.

Reasons Against Coloured Contact Lenses:

  • They Increase the Risk of Eye Infections: Contact lenses are made of hydrophilic polymers, which attract and retain water. This makes them an ideal surface for microorganisms to grow on, increasing the risk of eye infections. If you do not clean and disinfect your coloured contact lenses properly, you may increase your risk.

    Common monomers and polymers used in contact lens production. PMMA—poly methyl methacrylate, PVA—poly vinyl alcohol, PEG—poly ethylene glycol, DMA—dimethyl methacrylate, HEMA—hydroxy ethyl methacrylate, NVP—N-vinyl pyrrolidone, EGDMA—ethylene glycol dimethacrylate, PDMS—poly dimethyl siloxane, TRIS—3-[tris(trimethylsiloxy)silyl]propyl methacrylate. Source

  • Manufacturers Might Not Follow Strict Safety Standards: Coloured contact lenses are frequently regarded as cosmetic devices and are therefore not subject to the same regulations as medical devices. Some manufacturers may fail to adhere to strict safety standards, resulting in poorly made lenses that harm your eyes. It is critical to select a reputable brand and avoid purchasing lenses from untrustworthy sources.
  • Sharing Coloured Contact Lenses is a Big No-No: Sharing coloured contact lenses or wearing them for an extended period of time can increase the risk of eye infection. This is because the lenses can harbour bacteria, which can cause long-term damage to your eyes. It is critical to carefully follow the instructions and avoid sharing your lenses with anyone.

Reasons in Favour of Coloured Contact Lenses:

Different coloured contact lenses in the same individual. Source.

  • They Allow Personal Expression: Coloured contact lenses are a fun and versatile way to express yourself and your sense of style. You can switch up your look as often as you like because there are so many different colours and designs to choose from. This is especially appealing to those who do not want to commit to long-term solutions such as cosmetic surgery or tattoos.
  • They Are Made of Safe Materials: Coloured contact lenses are made of eye-safe materials such as silicone hydrogels or methacrylate-based polymers. These materials are designed to be biocompatible, which means they will not harm or irritate your eyes.
  • They Can Be Customized to Your Needs: Coloured contact lenses are available in prescription and non-prescription forms, allowing you to tailor them to your specific requirements. This is especially beneficial for people who need vision correction but want to experiment with different eye colours.

Finally, while coloured contact lenses can be a fun and exciting way to experiment with your personal style, it is critical to prioritize your eye health and safety. You can reduce your risk of eye infections and enjoy the benefits of coloured contacts by selecting a reputable brand, following proper cleaning procedures, and avoiding sharing your lenses. Whether you’re looking to enhance your natural eye colour or completely change your look, remember to prioritize your eye health and enjoy your new look with confidence!

~ Vivian Hou

Nanocrystals: The Science Behind Creamy Plant-Based Ice Cream

Ice cream lovers, get ready to indulge in a whole new level of creamy goodness! The secret ingredient? Nanocrystals.

These tiny particles, smaller than the width of a human hair, have the potential to revolutionize the world of vegan ice cream. Typically less than 100 nanometers in size, they can be made from a variety of materials, including cellulose, starch, and lipids. And here’s the exciting part: they can make vegan ice cream creamier than ever before!

Figure 1. Vegan vanilla ice cream. Source.

Traditionally, guar gum and locust bean gum (LBG) are the most commonly used stabilizers in ice creams. Recent research, however, suggests that cellulose nanocrystals (CNCs) may provide a more effective alternative. CNCs play an important role in improving the texture of plant-based ice cream by preventing ice crystal formation. This is due to nanocrystals’ unique properties which prevent them from growing larger. This results in a smooth and creamy texture comparable to traditional ice cream that consumers with dietary restrictions can enjoy.

 

But how do nanocrystals work their magic? The answer lies in the physics of freezing. When the water molecules in ice cream freeze, they can form large ice crystals. These large crystals, with diameters larger than 50 μm, impart a grainy texture to ice cream and can make it less creamy. Nanocrystals, on the other hand, can prevent this by enclosing the ice crystals in a protective shell, slowing their growth and keeping them small.

Figure 2. Ice growth kinetics of 0.5% CNCs, guar gum, and LBG in 25% sucrose solutions. Adapted from source.

Figure 2 shows that CNCs at 0.5% concentration can completely stop ice crystal growth after 72 hours. This is a significant finding because the same concentrations of guar gum and LBG had different effects. In the presence of CNCs, the final ice crystal size was approximately 37 μm, which was smaller than the final crystal size in the presence of guar gum and LBG. These findings show that CNCs can be a more effective stabilizer than traditional ones, as they can prevent ice crystal growth and result in smaller ice crystal sizes.

Smaller ice crystals can improve the creaminess, smoothness, and mouthfeel of ice cream.

It’s amazing how such small particles can have such a big impact on the quality of plant-based ice cream. Take a moment to appreciate the incredible chemistry happening in your bowl the next time you enjoy a scoop of your favourite non-dairy treat.

~ Vivian Hou

Nanodiamonds: A Breakthrough in Medicine and Cosmetics

Consider a diamond so small that it is measured in nanometers, but so powerful that it has the potential to change the way scientists approach cancer treatment and skincare.

Meet nanodiamonds, the tiny stones that are making waves in the fields of medicine and cosmetics worldwide. 

Illustration of nanodiamonds source

Basic structure of nanodiamonds with surface functional groups source

 

 

 

 

 

Nanodiamonds are overturning traditional cancer treatment methods.

Chemotherapy treatments, while effective, can have serious side effects. According to scientists, nanodiamonds provide new hope because they can selectively induce apoptosis, or cell death, in target cancer cells while causing no harm to healthy cells.

This makes them a game changer in the fight against cancer.

But that isn’t all.

Oxidative stress results from an imbalance between the activity of oxygen-containing free radicals and antioxidants in the cells and tissues of your body, leading to increased oxidation reactions. If there are more free radicals than antioxidants, the former can cause damage to fatty tissue, DNA, and proteins due to the lack of sufficient neutralizing agents.

Because of their ability to reduce this phenomenon, nanodiamonds can efficiently treat cardiovascular disease and inflammation. This makes them a potential force in the development of new therapies for chronic diseases.

Teradia TD Repair Serum Emulsion (serum composed of nanodiamonds) source

 

Nanodiamonds are used in a variety of cosmetic products, ranging from skincare creams to hair products and makeup.

They can improve skin texture and appearance, as well as reduce the appearance of fine lines and wrinkles, and increase skin hydration and elasticity.

This makes them an essential component of any anti-aging skincare routine.

 

For those who suffer from acne, nanodiamonds have antimicrobial properties that make them a popular ingredient in acne-fighting skincare products. They can effectively kill the bacteria that cause acne, reducing inflammation and aiding in skin clearing.

 

Nanodiamonds are small, but they pack a powerful punch. While more research is needed to fully understand the therapeutic and cosmetic benefits of these tiny diamonds, it is clear that they have the potential to change medicine and beauty forever.

Prepare to shine with nanodiamonds!

~ Vivian Hou