optional module 4: medicinal chemistry Flashcards
what diseases do mosquitos spread
malaria, dengue fever and the zika virus
how did insulin used to be exctracted
from the pancreas of cattle to treat children suffering from diabetes.
how is insulin extracted today
synthesised using bacteria or yeast to meet the public deamnd
where are synthetic drugs produced
in a laboratory, using chemical reactions to produce and isolate the acrive medicinal agent
where was asprin first extracted from
from the bark of willow trees,
how is asprin produced now
now made commercially by reacting acetic anhydride with salicylic acid. The product, acetylsalicylic acid, is then isolated from the other product acetic acid and purified from any other contaminants.
drug synthesis pathway
drug discovery
pre clinical
clinical trials (phase I, II, III)
review
manufacturing phase IV
what is combinatorial chemistry
a laboratory method that involves using robotics to synthesise thousands of different compounds at a time, usually peptides or small molecules. The compounds can then be tested for effectiveness, and then kept for further testing or modification, or discarded. With this highly automated process, large volumes of molecules can be synthesised and tested in a short period of time, but it is more of a trial-and-error approach, resulting in a large amount of molecules made that have no activity. Although it is difficult for scientists to mimic natural processes, combinatorial chemistry is proving to be making new advancements in drug discovery.
what is a double blind test
where a placebo is offered to one group of patients while the other group recieves the drug
what is a placebo
a pill, lotion or injection that does not contain the active ingredient that the drug has, and is used to see if the drug does have a measurable effect compared to not using the drug.
methods of drug administeration
Ingestion by mouth (e.g. pills or syrups).
Injection with a syringe under the skin into fat or muscle tissue or bloodstream.
Inhalation by mouth or nose (e.g. as with an inhaler or nebuliser).
Absorption through the skin (e.g. medicated lotions or stick-on patches).
Absorption in the rectum or vagina (e.g. suppositories).
Applied into the ear or eye (e.g. drops of prepared solutions).
what does oral medicine require
the medicine to be absorbed by the digestive tract
what is the speed and ability of the body to absorb medicine called
metabolism
what determines method of administeration
dosage (grams or millilitres)
frequency of administeration
tolerance of the drug
side effects
what can help to prevent against addiction
A slower, time-released method, such as with oral ingestion or a skin patch, can help to keep the levels of medicine in the body lower and more consistent, and avoid dependency.
in animals, the theraputic index is the lethal dose of the drug for
50% of the population (LD50) divided by the minimum effective dose for 50% of the population (ED50)
in humans, the theraputic index is the toxic dose for
50% of the population (TD50) divided by the minimum effective dose for 50% of the population (ED50)
the theraputic window is
the range of dosages between the minimum amounts of the drug that produce the desired effect and a medically unacceptable adverse effect
theraputic index
the effective window where the dosage of the drug is most active
lethal dose
the dose of the drug that is enough to kill half of the population
toxic dose
upper limit of the therapeutic window
doage
amount of drug given
aims of drug administration
dosage, tolerance, addictiona nd side effects
what is bioavailability
the fraction of the administered dosage that reaches the target part of the human body
drug receptor interactions are based on
the structure of the drug and the site of the activity
therapeutic index for animals:
ED50
what is the ED50
the effective dose for 50% of the population
what is the LD50
the amount of drug required to kill 50% of the animal population
in humans, the LD50 cannot be determined experimentally and animals raise ethical concerns so what is used instead
the toxic dose
the smaller the value of the therapeutic index…
the more dangerous the drug because the minimum effective dose and the toxic or lethal doses will be similar
how can drugs be administered
enteral (oral, sublingual, buccal, rectal)
parenteral (injection)
topical (enepidermic, epidermic, insufflations, instillation, irrigation, swabbing)
what is subcutaneous injection
directly under the skin, usually for small volumes of drugs, eg insulin and vaccinations. intramuscular is usually injected into the arm, leg or buttocks and used for larger volumes of drug or when a vein cannot be found if the drug irritates veins
intravenous injection hs the most rapid effect as the drug enters the bloodstream directly. when a medicaiton is administered intravenusly, the bioavaila bility is
100%
why is bioavailability not always 100%
acidity of the stomach or small intestine may destroy some of the drug, the drug may not be completely absorbed or it might even be absorbed by the bacteria in the small intestine
factors that affect bioavailability
degree of ionisation
solubility in lipids
form of dosage
concentration of dosage
why must drugs have some polarity
to reach blood (polar solvent)
why must drugs have some non polarity
to pass through the cell membrane
polar functional groups
hydroxyl, carboxyl, amino
non polar functional groups
alkyl side chains
phenyl rings
if a drug is administered orally, then it will generally dissolve
within the poalr environment of the contents of the stomach
if the drug is not very polar
it might bind to food particles instead, preventing it from being absorbed. this is why drugs are sometimes required to be taken either with food or on an empty stomach to ensure better absorbption (and thys greater bioavailability)
what is tolerance
a decrease in effectiveness of a drug as it is used more
dependence can occur when
reducing or stopping the dosage of a drug leads to physical withdrawl symptoms
heroin is a derivative of
morphine
what is a placebo
does not contain the active ingredient of the drug and is used to compare to the drug
what is the type of test called when neither the test takers or the researchers know which partakers receive active substance and which ones receive placebo
double blind
what is bioavailability
the fraction of an administered dose of the medicine that reaches the target site.
on a molecular level, drugs interact with the
receptors in cell cytoplasm
receptors in cell membranes
what did asprin used to be prepared from
willow bark
what is asprin prepared from now
salicylic acid and acetic anhydride/ethanoic anhydride
what type of reaction forms asprin
esterifcation to produce acetylsalicylic acid (asprin) and acetic acid
what does esterification require
acid catalyst
how can aspirin crystals be collected
by filtration (gracimetric or vacuum filtration) when the mixture cools in an ice bath following the reaction
how is purity of a product improved
recrystallisation
what is recrystallisation
generally involves taking the dried white crystals that were obtained and dissolving them in warm 95% ethanol in a flask. When the crystals have all been dissolved, an equal volume of water is added and the contents cooled on ice until the aspirin crystals recrystallise (and return to white). The sample is then filtered again, and recrystallisation can be repeated many times to ensure improved purity of the sample. This process works by removing impurities by dissolving them in ethanol, which has polar and nonpolar properties. The impurities will dissolve and be rinsed away with the ethanol/water mixture, leaving behind the pure aspirin crystals, which have a melting point of 136°C, meaning it will become a solid when cooled to room temperature.
process of recrystallisation
dissolve compound in a minimum amount of hot solvent (ethanol)
allow solution to cool to room temp so that crystals form slowly
filter crystals by suction using a hirsch or buchner funnel. wash crystals with fresh, cold solvent
melting point range
the sample can melt over a range of temps
an impure sample will have a melting point lower than the…
theoretical temperature
why do impure substances have lower temperatures
they have impurities that disrupt the crystalline structure, weakening the attractive forces between particles. the lower the purity, the greater temp difference from the theoretical melting point and the broader the melting point range
how can purity be tested
infrared spectroscopy
analgesics
medicines that provide relief from pain (analgesia). Some different analgesics include aspirin, acetaminophen/paracetamol and opiates. Some analgesics work at the site of the trauma while others work in the brain to alter the perception of pain.
what is asprin used for
pain reliever, fever reducer and anticoagulant
potential side effects of asprin
can irritate the stomach and lead to ulcers
causes blood to thin
how is asprin often prescribed
people with a risk of heart attack or stroke
during pregnancy to reduce the risk of certain pregnancy complications
to improve circulation for people with diabetes
how does asprin work for pain relief or fever
asprin stops the enzyme that produces prostaglandins which is cyclooxygenase.
what happens when we experience physical trauma
the cells in our body respond with a series of steps that ends with the production of chemical substances called prostaglandins. the cells in our body respond with a series of steps that ends with the production of chemical substances called prostaglandins.
analgesics are
pain relievers
antipyretics are
fever reducers
what is asprin, an analgesic or an antipyretic
both
why is blood slightly viscous
due to the presence of dissolved fats, proteins and other components.
what is coagulation
when platelets clump together/clot
what happens in haemophilia
the blood doesnt clot well so the person can lose a lot of blood
what happens if blood vessels becom blocked
parts of the body cant recieve nutrients. plateltes also contirbute to blockage by percieving it as damage.
If the blockage occurs in the artery leading to the heart,
the heart begins to pump harder to draw more blood toward itself and the heart muscle becomes damaged. This is called a myocardial infarction, or commonly a heart attack.
If the blockage occurs in the artery leading to the brain,
blood and the oxygen it carries do not reach the brain, causing damage. This is called a stroke.
asprin slows down clumping of platelets so they…
anticoagulate
what is a prophylatic
to slow or prevent the formation of a blockage in the first place.
how can asprin be chemically modified to a salt to increase its solubility in aqueous solutions
By dissolving the acetylsalicylic acid in sodium hydroxide, the hydrogen on the carboxyl functional group is replaced by a sodium ion, as shown in the reaction below, to make sodium acetylsalicylate, sometimes called soluble aspirin.
why is the sodium acetylsalicylate product is more soluble in water than the aspirin molecule
ions have a stronger attractive force to the dipoles in water molecules than the intermolecular forces of the carboxyl functional group
what is the benefit of having a product with greater aqueous solubility
it means that orally ingested sodium acetylsalicylate will reach the stomach more quickly
why is The bioavailability of soluble aspirin, however, is almost the same as the insoluble form
because the ionic salt reacts with stomach acid to produce (insoluble) aspirin.
describe a method to inrease the bioavailability of asprin
administer the drug intravenously
what type of effect do asprin and alcohol have
a synergistic effect:
each drug has a higher medicinal effect when taken in combination than they would when taken separately.
why should you not consume asprin and alcohol simultaneously
to avoid te increased risk of stomach bleeding or other toxic effects
how do communicable diseases usually spread
through bacteria or viruses
bacteria are
single-celled organisms that divide by binary fission within the organism that they have infected.
how can bacterial infections be treated
with antibiotics, like penicillin that stop its growth and production
viruses are
small capsules of DNA (deoxyribonucleic acid, which is genetic material) that require a host organism in order to replicate. Viruses are much smaller than bacteria and do not contain the organelles necessary to divide on their own.
how can viral infections be treated
immunization the only option really
how is industrial pencillin produced
its fermented in large stainless steel tanks in sterile environments. In order to produce a stressful environment, scientists provide penicillin with lactose sugar, rather than glucose sugar that the fungus prefers as a food source. The temperature, pH and other nutrients added to the batch also ensure that the fungi are under stress. then the pencillin is seperated from the mold and is purified for use as an antibiotic medicine
how is the fungi held under stress
lactose sugar (not glucose) temperature, pH and other nutrients
what is the mold that produces pencillin called
penicillium mold
CORE STRUCTURE OF PENCILLIN
(D.2 synthesis of pencillin)
what is the becta-lactam ring
the func group of penicillin. important for the action of pencillin in preventing bacterial growth
what can benzyl penicicillin treat
syphilis, meningitis and other bacterial infections
if pencillin contains a benzene ring, what changes in its treatment
it must be injected as benzene is non polar so is not water soluble enough to be absorbed by oral ingestion
whats penicillin V
oxygen before the benzene ring
benefit of pencillin V
slightly more solubility so can be prescribed as an oral antibiotic to treat minor infections like tonsilitis. is stable in an acidic environment
which environment is pencillin g not stable in
acidic, so it cannot be taekn orally and must be injected to have better bioavailability
how is ampicillin produced
by chemically modifying the R group to include an amino group.
benefit of ampicillin
The presence of this amino group allows ampicillin to better penetrate the cell walls of bacteria and thus has greater action on stopping the growth of bacteria for respiratory infections. The amino group also allows for greater solubility in water, so ampicillin is often prescribed orally, rather than intravenously.
what are cell walls made of
peptidoglycan, a polymer made of sugars and amino acids, aka murein, sandwiched between two lipid layers.
what would happen without a functioning cell wall in a bacterium
it would not have the rigid structure required to function and would instead rupture, causing the death of the cell.
what is the cross linking of cell walls
covalent bonds holding the layers together (common in polymers)
benefits of cross linking in cell walls
additional structure and rigidity
how does cross linking occur
by the action of certain enzymes like transpeptidase. the penicillin binding protein (PBP). the beta lactam ring effectively binds to the transpeptidase
how does cross linking occur
by the action of certain enzymes like transpeptidase. the penicillin binding protein (PBP). the beta lactam ring effectively binds to the transpeptidase (PBP) and interferes with the action of the enzyme, not allowing the cell wall to be cross linked. a lack of cross linking will have too much water entering via osmosis causing the cell to burst.
sme bacteria are capable of producing enzymes that destroy pencillin
penicillinase or becta-lactamase
how does penicillinase work
to break the beta-lactam ring in the penicillin molecuel, thus rendering it ineffectice in binding to transpeptidase (also known as the penicillin binding protein)
having a bulkier larger r group seems to make penicillin more
resistant to penicillinase, so naturally-occurring penicillins can be chemically modified to make penicillin more effective at stopping the growth of bacteria.
waht is opium
the dried latex of the opium poppy
what is latex
milky fluid produced by some flowering plants and contains a mixture of polymers, sugars, oils and proteins. Latex from plants can be used to make a variety of consumer products including balloons, chewing gum and paint. Opium latex was observed to have medicinal properties as early as 5000 BC
opiates
generally refer to naturally occurring analgesics obtained from the opium poppy or synthetic derivatives made from the naturally-sourced medicine. Examples include morphine, codeine and diamorphine (heroin).
opioids
generally refer to synthetically produced drugs that mimic the action of naturally occurring opiates. Examples include oxycodone and hydrocodone. These drugs have been under a lot of legal and ethical scrutiny for their highly addictive nature.
cultivation of opim poppies
originally mediterranean
now turkey, england, india for pharmaceuticla compnies legally.
illegal cultivation has occured in myanmar, thailand, laos since ww2, and has grown in afghanistan in recent years (largest producer of illegal opium)
active medicinal ingredient in opium is
morphine
opium latex contains about
12% morphine so it must be refined to purify and make the sample more potent
traditional puppy cultivation involves
making incisions in the seed pod and collecting the dried latex. The latex is then processed to extract the morphine, which can then be taken intravenously or orally.
morphine can also be used to make
codeine, an analgesic used to treat a mild-to-moderate degree of pain, and heroin, a highly addictive analgesic, which is illegal in many countries.
what is diamorhphine known as
heroin
opiates must travel to
the brain (through blood as they have polar functional groups) where they interfere with nerve impulses. however the brain is surrounded by a layer of lipids or fats which are highly nonpolar. there must also be enough nonpolar functional groups
what functional groups does morphine have
two hydroxyl which add polarity and water solubility to the structure.
how is morphine prescribed
Morphine is prescribed orally in a tablet or liquid or by intramuscular or intravenous injection.
bioavailability of oral morphine
30%
codine functional group
one hydroxyl substituted with an O bonded to a methyl alkyl functional group which forms an ether and therefore slightly decreasing the polarity and water solubility compared to morphine (allowing for a higher bioavailability)
bioavailability of codeine orally
90%
cons of codeine
less effective at binding to receptors in the brain and therefore has 1/10 the strength of morphine, so it is only suitable for mild to moderate pain.
diamorphine functional groups
two hydroxyl substiuted with O boinded to an acetyl side chains which forms 2 ester groups and greatly reduces the polarity and solubility in water compared to morphine and codeine
bioavailability of diamorphine orally
less than 35% so generally taken intravenously
with the decrease in polarity of diamorphine what happens
diamorphine can pass into the brain much more easily than both morphine or codeine. It also binds to the receptors in the brain more effectively than both morphine and codeine, making diamorphine have 4-5 times the strength of morphine.
opium latex contains how much codeine
3%
what is codeine sometimes referred to as
methylmorphine since one hydroxyl functional group is replaced with a methyl alkyl group via a methylation reaction.
what is codeine sometimes referred to as
methylmorphine since one hydroxyl functional group is replaced with a methyl alkyl group via a methylation reaction which makes an ether linkage. This reaction is actually reversed in the liver when the body is breaking down the codeine for elimination.
methylation diagram codein
d3
which is not found in opium latex
dimorphine (heroin)
how is dimorphine made
it is only made synthetically by reacting morphine with ethanoic acid in an esterification reaction. The hydroxyl functional groups on the morphine molecule each react by a condensation reaction with the carboxylic functional group on the ethanoic acid. The result is an ester linkage and the elimination of water.
what happens when the body recieves trauma
a chemical pathway occurs with the end result being the production of prostaglandins.
what do prostaglandins do
increase the body’s temperature, causing a fever, and are also part of producing the sensation of pain.
what causes the sensation of pain
by the direct action of prostaglandins on the nerve endings locally at the site of the trauma or by acting on the perception of pain in the central nervous system in the brain.
what happens when the CNS receives a pain stimulus from the nerve endings at the site of a trauma
the pain signal is transmitted through the nerve cells, called neurons, to the spinal cord and then the brain. Neurons can communicate to one another using chemicals called neurotransmitters, to transmit the signal faster and across small gaps between neurons, called synapses, where they interact with receptors on the neuron on the other side of the synapse. Specific parts of the brain are then stimulated to give the sensation of pain.
how do opiates work
by interfering with the neurotransmitters and receptors in the transmission of the pain signal across
what are endorphins
work as natural pain relievers
Endorphins bind to what
endorphin receptors (also called opioid or opiate receptors) in brain cells to intercept the pain signal.
what do opiates bind to
the same endorphin receptors since they have the same chemical structure as endorphins (so the body cant tell)
what is the implication of “dopamine is a neurotransmitter that is produced when the endorphin receptor binds to a natural endorphin or to an opiate.”
The release of dopamine causes feelings of pleasure, which adds to the addictive nature of opiates.
side effects of enorphin receptors
All three receptors respond with analgesia (pain relief), but each one also produces other side-effects, ranging from hallucinations and anxiety to respiratory depression, nausea and constipation. These side-effects are the result of chemical changes that occur in the body in response to the binding of the opiate or endorphin to the endorphin receptor.
which chemicals can bind to endorphin receptors
morphine codeine and diamorphine
codeine is what strength of morphine
1/10
how is codeine turned tom orphine
must first be metabolised in the liver back into morphine. This conversion is quite slow and other products are also made, which have no medicinal effect.
why is dimorphine faster at crossing into the lipid layer that surrounds the brain
contains more nonpolar functional groups than morphine or codeine,
Diamorphine can only bind to one receptor, so the effect of diamorphine is
is immediate, but does not last long.
morphine most common method of administeration
Oral tablet or liquid (30% bioavailability).
Intramuscular or intravenous injection (100% bioavailability).
codeine most common method of administeration
Oral ingestion (90% bioavailability).
diamorphine
Oral ingestion (35% bioavailability).
Intravenous injection (100% bioavailability).
morphine relative strength
1
codeine relative strength
0.1
diamorphine relative strength
4-5
morphine common medicinal uses
Quick moderate to severe pain.
Sedation for minor surgical procedures.
codeine common medicinal uses
Mild pain.
Cough suppressant for non-productive cough (one that does not clear mucus from the airways).
diamorphine common mediicnal uses
severe pain
morphine adv
Quickly relieves pain.
Mild side effects.
Option for convenient administration (oral ingestion)
codeine adv
Suitable for mild pain.
Drug is slowly metabolised, so fewer doses are required.
Convenient administration.
diamorphine advantages
Very quick relief from pain.
morphine disadv
Moderately addictive.
Withdrawal if taken for extended periods.
codeine disadv
Addiction is possible.
diamorphine disadv
Highly addictive.
Must be injected.
Withdrawal if taken for extended periods.
Drug metabolises quickly, so frequent doses are required.
use of morphine example
Morphine is used for moderate to severe pain, such as following surgery, during childbirth or after breaking a bone. Morphine can also be used effectively for sedation in minor surgical procedures, such as during wisdom tooth surgery.
codeine use example
Codeine, the mildest opiate, is prescribed for minor pain, such as a headache, but is also used as a cough suppressant. Codeine is metabolised slowly by the liver back into morphine, making it useful as a long-lasting analgesic for low levels of pain. Some people, however, are able to metabolise codeine very quickly, converting it to morphine at a dangerous speed, so codeine cannot be prescribed for all people.
diamorphine use
The use of diamorphine as a treatment for severe pain is controversial, due to its highly addictive nature. Since it is a stronger analgesic than morphine, it can be administered at lower doses. It is effective in alleviating severe chronic pain, such as for patients in end-of-life stages (palliative care) suffering from terminal illnesses. It is also used for pain relief following childbirth by caesarian section and even in children suffering from severe post-operative pain.
asprin acts
at the local site of trauma
where does morphine act/effect
morphine affects the body’s central pain response in the brain, so there are more side effects. Common side effects that are mild include feeling dizzy, drowsiness, constipation and weight loss. More serious side effects include blurred vision, chest pains and difficulty breathing. Symptoms of an overdose can include constricted pupils, fever, muscle pain or spasms and severe sleepiness.
can you build a tolerance to opiates
yes due to the opiate receptors undergoing changes to become less sensitive to the opiates. For people taking opiates for extended periods of time, higher doses of the drug are required to have the same medicinal effect. Doctors must be careful when prescribing opiates for patients long term because of desensitisation.
what is tolerance
decreased medicinal effect of a drug that occurs with extended use of the same dosage. Certain medicines cause a physiological response in the body, making the same dosage of the medicine not as effective. In order to achieve the same medicinal effect, the dosage must be increased with time.
symptoms of withdrawl
include sweating, vomiting, muscle aches and psychological distress.
what is methadone
an opiate derivative that can bind to the opiate receptors but does not produce the euphoric effects of morphine. Methadone is an effective treatment option to help with tolerance, addiction and withdrawal symptoms.
opiates can produce what at high doses
Opiates can produce a euphoric sensation at high doses, which results in illegal use and addiction.
what lifestyle factors put people more at risk of excess stomach acid production eg…
A diet high in spicy, fatty or acidic foods, such as chilli peppers, coffee, citrus fruits and alcohol, can increase stomach acid production. Stress, lack of sleep or certain medical conditions can also increase stomach acid production. Eating very large meals, lying down after eating or even excess pressure on the stomach during pregnancy can push the stomach contents, including acid, up into the oesophagus, causing the same symptoms.
how to combat excess stomach acid production
Traditional treatments for excess stomach acid include baking soda (sodium hydrogen carbonate), aloe vera juice or ginger root tea to neutralise the acid. Apple cider vinegar, also acidic, has proven effective in decreasing stomach acid production. Currently, medicines offer quick and effective relief, either by neutralisation or by decreasing acid production.
what are antacids made of
Antacids can be made from a variety of compounds, but must contain a base in order to neutralise the excess hydrochloric acid produced by the stomach. The base must not be a very strong base, as it could cause damage to the mouth and oesophagus on the journey to the stomach. Many brands of antacids contain calcium carbonate, a white powdery solid that is easily pressed into a tablet, and other compounds, such as flavourings, colours and binding agents. When chewed and swallowed, the calcium carbonate reacts with hydrochloric acid in a typical neutralisation reaction:
antacid neutralisation reaction
CaCO3 (s) + 2HCl (aq) → CaCl2 (aq) + CO2 (g) + H2O (l)
give another reason for taking antacids
to support healthy bone development
what must be present for calcium carbonate to be well absorbed
vitamin d
how does calcium carbonate help with neutralising stomach acid
The products of calcium chloride, carbon dioxide and water, are neutral, so they will not further aggravate the stomach. The calcium carbonate does not neutralise all of the stomach acid, but just some, in order to leave sufficient acid for digestion.
what else is in antacids
Other additives are included in the antacid tablet, including flavouring, colour and antifoaming agents to decrease bloating from the carbon dioxide gas that is produced during neutralisation. Different brands of antacids use different bases, but the concept is still the same. Here are some examples of other antacids.
neutalisation reaction aluminium hydroxide
Al(OH)3 (s) + 3HCl (aq) → AlCl3 (aq) + 3H2O (l)
neutalisation reaction magneisum hydroxide
Mg(OH)2 (s) + 2HCl (aq) → MgCl2 (aq) + 2H2O (l)
neutalisation reaction calcium hydroxide
Ca(OH)2 (s) + 2HCl (aq) → CaCl2 (aq) + 2H2O (l)
neutalisation reaction sodium carbonate
Na2CO3 (s) + 2HCl (aq) → 2NaCl (aq) + CO2 (g) + H2O (l)
neutalisation reaction sodium bicarbonate
NaHCO3 (s) + HCl (aq) → NaCl (aq) + CO2 (g) + H2O (l)
why do pregnant women often get heartburn
due to excess stomach acid production and/or pressure on the stomach from a growing baby, pushing stomach contents upward into the oesophagus. Certain antacids are considered to be safe for use during pregnancy, but some are associated with increased risk of birth defects. In general, calcium- and magnesium-based antacids are considered to be safe, but sodium-based antacids are not recommended as they can lead to high blood pressure, causing other pregnancy complications.
how would you calculate the amount in mol of acid that can be neutralised by the base, using the mass and molar mass of the base or using the vol and conc of the liquid antacid
n = mass/mr
mg to g
divide by 1000
what is the stomach buffer system to regulate stomach acidity
Buffers are solutions that resist changes in pH when small amounts of strong acid or strong base are added. If acidic or basic foods are consumed or small amounts of stomach acid are produced or used up during digestion, the pH of the stomach contents can be ‘buffered’ and maintained within an optimal range of pH 1 to 3.
what should th esotmach pH be
1-3
