Ideaz

M.A.R.S

Multiplex Antibiotic Resistance Screening

"Rapid results for confident treatment"

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1️⃣ The Problem 

• Doctors hand out broad-spectrum antibiotics “just in case” all the time — without knowing if the bacteria is resistant or not.
• This is because lab tests take 2–3 days (culture + sensitivity testing).and so they give any antibiotic for temporary purposes.
• If the antibiotic doesn’t work, the infection worsens, and stronger drugs are given → this fuels the rise of superbugs (multidrug-resistant bacteria).
• WHO reports ~5 million deaths annually linked to antimicrobial resistance (AMR).
• Hospital stays become longer, costlier.
• Last-line drugs (carbapenems, colistin) are failing in some countries.
• Core of the problem: Diagnosis is too slow and too inaccessible. By the time doctors know the bacteria & resistance profile, the wrong antibiotic may already have been used.

2️⃣ The Gap in the Market  

• Culture-based tests: Accurate but slow (2–3 days) and require lab infrastructure.
• PCR/Sequencing: Expensive, technical, and limited to specific genes.
• Current rapid tests: Single-target or require instruments.

M.A.R.S fills this gap:

• Rapid (<1 hour) and easy to use.
• Detects multiple resistance genes at once (multiplex).
• Affordable (~$5–10 per test).
• Works in clinics, rural hospitals, and low-resource settings.

3️⃣ The Solution – M.A.R.S 🎯
The M.A.R.S. test is a rapid, point-of-care diagnostic tool designed to quickly screen for multiple antibiotic resistance genes directly from a patient sample. By providing rapid, actionable genetic information, M.A.R.S. allows clinicians to make informed treatment decisions, prescribe targeted antibiotics, and avoid the use of broad-spectrum drugs.

How it works:

M.A.R.S is a palm-sized test cassette:

1. Sample collection
   Swab blood, urine, or wound → put sample in a small lysis buffer to release bacterial DNA.
2. Loading the sample
   Add drops of buffer + sample to the preloaded wells on the cassette.
3. Reaction inside the well  --Each well has freeze-dried Cas enzyme + guide RNA (gRNA) + reporter molecule.
   
   1. Colorimetric readout
   • Reporter molecule = ssDNA/RNA tagged with dye + quencher.
     • Intact → quencher blocks dye → invisible\/no change in colour
     • Cut by Cas → dye released → visible red color
   • Color guide for clinicians:
   1. No colour change = no resistance detected
   2. Red = resistance gene detected.
4. • Interpretation (30–45 min)
   • no colour change → safe to prescribe standard antibiotics
   • red well → avoid that antibiotic class
   •  Multiple red lines → multidrug resistance → escalate treatment.

4️⃣ Scientific Mechanism 

1. Sample in buffer

• Lysis buffer breaks open bacteria → releases DNA/RNA.
• Stabilizes nucleic acids and prevents degradation.

1. CRISPR detection

• Cas enzyme + gRNA scans the solution for target DNA/RNA.
• gRNA binds only to the resistance gene sequence it is specific to.

• gRNA is programmed to detect a specific resistance gene:

  • mecA → MRSA (methicillin resistance)

  • blaNDM → carbapenem resistance

  • vanA → vancomycin resistance

  • qnrB → quinolone resistance

  • aac(6’) → aminoglycoside resistance

• When gRNA recognizes the specific resistant gene, it activates Cas and Cas changes shape upon binding → activates collateral cleavage.

1. Reporter cleavage → color change

• Reporter floats freely in the well:

                                Dye — ssDNA/RNA — Quencher

• So essentially if the guide RNA (gRNA) detects the presence of antibiotic resitant gene in the sample loaded then it binds to it like a lock and key model and the freeze dried cas enzyme then recognizes and cuts the specific resistant gene fragment and has a function called ‘collateral cleavage’ where it not just the target sequence but also the reporter molecules present nearby and dye is released if resistance gene is detected, otherwise the cas is not activated and no cutting occurs so reporter is not cut and dye is not released.
• Cas cuts reporter → dye separates from quencher → red color appears.
• If no target → Cas inactive → reporter intact → no color.
• Multiplexing: Each well/line targets a different gene → simultaneous detection of multiple resistances.

Patient sample → lysis buffer → DNA released

         │

         ▼

   Well with Cas/gRNA + Reporter

         │

Target DNA present? ──► Yes ──► Cas activated → reporter cut → Red color

         │

         No ──► Cas inactive → reporter intact(dye stays quenched) → no colour change

5️⃣ Who Does it Benefit? 

• Patients → get effective treatment fast, fewer complications.
• Doctors/Hospitals → prescribe confidently, reduce hospital stays and costs.
• Public Health → slows spread of superbugs, reduces broad-spectrum antibiotic misuse.

6️⃣ Why It Matters to Me 

Antibiotic resistance is a worldwide problem that affects countless lives. The ability to create rapid diagnostics like M.A.R.S(Multiplex Antibiotic Resistance Screening) is very useful because it tackles the problem at its core: preventing the misuse and overuse of antibiotics. As a biotech student and future professional in this field, the idea of providing clinicians with immediate, accurate information to prescribe the right antibiotic – or even avoid one when unnecessary – is incredibly motivating. It's about shifting from broad-spectrum guesswork to precision medicine, a concept I'm passionate about. This project is a way to :empower healthcare with fast, clear, and actionable results that can be used effectively in any clinical setting, truly making a difference in the fight against superbugs.

7️⃣ Road Map to Market  

1. Prototype: Build cassette/strip with M.A.R.S reporters.
2. Lab testing: Confirm target detection in bacterial cultures.
3. Clinical validation: Test on patient samples → compare with gold-standard culture.
4. Regulatory approval: In vitro diagnostic (IVD) certification.
5. Launch: Hospitals → rural clinics → pharmacies for point-of-care use.
6. Expansion: Add more resistance genes, new infections (TB, gonorrhea, hospital-acquired infections).