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NONCOVALENT FORCES

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NONCOVALENT FORCES

Happen between molecules.

Not sharing electrons or forming new bonds.

Affect physical properties.

Require specific conditions to be present.

Hydrogen bonding, dipole-dipole forces, Van der Waals forces.

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HYDROGEN BONDING

Hydrogen bonds are weaker than ionic and covalent bonding

Strongest of the 3

noncovalent forces

Nitrogen, oxygen, or fluorine interacting with a hydrogen bonded to a nitrogen or oxygen

Salbutamol and salmeterol interact with proteins via hydrogen bonding

Water,

Glucose,

Isopropyl alcohol (rubbing alcohol)

N O F

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DIPOLE–DIPOLE FORCES

No covalent bonds are formed in dipole–dipole forces

Dipole–dipole forces are the 2nd strongest noncovalent force

Molecules must be polar or have a polar bond

A polar molecule is one that has uneven charge distribution

HCl, Formaldehyde, Acetone (Nail polish remover)

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No covalent bonds are formed in Van der Waals forces

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Van der Waals forces are the weakest type of noncovalent interaction

Attractions caused by induced dipoles

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Strength of interaction is dependent on distance between the two molecules

Salmeterol, Octane, Methane

VAN DER WAALS

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IMPACT

SYMPTOMS

CAUSES

TREATMENT

IF WE RECALL ASTHMA…

Two main types of inhalers:

  • bronchodilators (such as salbutamol)
  • steroids (such as beclometasone)

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Salbutamol (Albuterol, VentolinTM)

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IMPACT

SYMPTOMS

CAUSES

TREATMENT

Asthma is often under-diagnosed and under-treated, particularly in low and middle-income countries.

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People with under-treated asthma can suffer sleep disturbance, tiredness during the day, and poor concentration.

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  • A persistent cough, especially at night
  • Wheezing when exhaling and sometimes when inhaling
  • Shortness of breath or difficulty breathing, sometimes even when resting
  • Chest tightness, making it difficult to breathe deeply.

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  • Asthma is more likely if other family members also have asthma.
  • Asthma is more likely in people who have other allergic conditions.
  • Urbanization is associated with increased asthma prevalence.
  • Events in early life affect the developing lungs and can increase the risk of asthma.
  • Exposure to a range of environmental allergens and

Two main types of inhalers:

  • bronchodilators (such as salbutamol)
  • steroids (such as beclometasone)

IF WE RECALL ASTHMA…

Salbutamol (Albuterol, VentolinTM)

  • Fast-acting, 15–20 minutes.
  • Hydrogen bonding to receptor.

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Salbutamol (Albuterol, VentolinTM)

  • Fast-acting, 15–20 minutes
  • Hydrogen bonding to receptor

Salmeterol (SereventTM, AdvairTM)

  • Long-acting, over 12 hours
  • Hydrogen bonding to receptor
  • Van der Waals interactions with cell membrane

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Salbutamol

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Salmeterol