RNA extraction (HCV RNA) using trizol method

Main ideas / concepts conveyed

• Purpose: Demonstrate an RNA extraction method to obtain HCV RNA (described as “ACV/ACB” in subtitles) from patient samples, so that viral load can be calculated later.
• Background concept:
  • The virus is treated as an RNA virus.
  • Viral load is required for treatment decisions (e.g., medicine dose).
  • The key prerequisite before viral load calculation is extracting RNA from patient samples.
• Overall workflow: Use a Trizol/lysis-based chemistry + silica column purification approach with multiple reagents:
  1. Lyse the virus and release RNA
  2. Separate phases to isolate the RNA-containing aqueous phase
  3. Precipitate RNA using alcohol
  4. Bind RNA to a silica RNA-binding column
  5. Wash to remove contaminants
  6. Elute purified RNA for downstream viral load testing

Reagents mentioned and their described roles (kit-based; “GCC biotech kit”)

1. “Tisen/lysis reagent” (Trizol-like lysis reagent)

   • Lyses/destroys virus, releasing RNA into solution.

2. Isopropanol

   • Used to precipitate RNA.
   • Concept: nucleic acids are water-soluble, and alcohol makes them insoluble, leading to precipitation.

3. Chloroform

   • Used for phase separation (“face separation” in subtitles).
   • Helps separate into:
     • Aqueous phase (top): where RNA is collected
     • Interface (middle): associated with DNA
     • Organic phase (bottom): where proteins remain
   • Emphasis: collect only the clear aqueous phase.

4. Membrane wash buffer (alcohol/ethanol-containing)

   • Used to wash the column and remove unwanted proteins/contaminants.
   • Cannot remove RNA once RNA is bound to silica.

5. Nuclease-free water

   • Used as elution buffer to recover RNA from the column.

Sample information

• The speaker states they collected five patient samples from individuals who are HCV-positive (subtitles mention “ACB positive/serology”).
• The extracted RNA is intended for viral load determination, supporting treatment dosing.

Step-by-step methodology (as presented)

Amounts/times are transcribed from subtitles; there are likely minor errors due to auto-captioning.

A) Lysis and initial mixing

• Label five microcentrifuge tubes with sample numbers.
• Add 800 µL lysis reagent (“tisine reagent”) to each tube.
• Add 200 µL patient sample to the corresponding tube.
  • Emphasis: use exact volumes (200 µL). Too little/too much may affect viral load accuracy.
• Mix appropriately, then:
  • Incubate at room temperature for 5 minutes
  • Keep lids closed during incubation.

B) Chloroform addition and phase separation

• Add 200 µL chloroform to each tube.
  • Caution noted: chloroform is hazardous; add carefully.
• Close lids tightly.
• Invert tubes 5–10 times to mix.
• Centrifuge: 12,000 RPM for 5 minutes
• Identify the phases:
  • Top clear aqueous phase: collect only this (RNA-containing)
  • Middle interface: described as where DNA resides
  • Bottom organic phase: where proteins remain
• Transfer the aqueous phase to a new tube.
  • Emphasis: avoid aspirating the interface or organic layer.

C) Alcohol precipitation (with isopropanol)

• Add 200 µL isopropanol to the collected aqueous phase in each tube.
• Vortex to mix thoroughly so precipitation occurs.

D) RNA binding to silica column

• Prepare an RNA binding column (silica-based) connected to a collection tube.
• Load 700 µL “supernatant” onto the binding column.
  • Emphasis: capacity may limit total volume; use 700 µL as stated.
• Centrifuge: 12,000 RPM for 30 seconds (room temperature).
• Discard flow-through (RNA remains trapped in the column).
• Transfer the leftover solution back onto the column and repeat:
  • Centrifuge: 12,000 RPM for 30 seconds
  • Discard flow-through again.

E) Washing steps (membrane wash buffer)

• Add 600 µL membrane wash buffer to each binding column.
• Centrifuge: 12,000 RPM for 30 seconds
  • Subtitles show 30 seconds; captions mention a timing discrepancy (earlier also says ~1 minute).
• Discard the wash buffer (do not discard the collection tube).
• Repeat once more:
  • Add another 600 µL wash buffer
  • Centrifuge: ~1 minute (or 30 seconds as an option stated)
• After final wash:
  • Discard flow-through from the collection tube.

F) Dry spin

• Perform a dry spin without adding reagent:
  • 12,000 RPM for 30 seconds to 1–2 minutes
• Example given:
  • Cooling centrifuge at 23°C
  • 12,000 RPM for 1 minute

G) Elution

• Move the column to a clean collection tube (discard the prior collection tube).
• Add 60 µL nuclease-free water directly to the column.
• Centrifuge: 12,000 RPM for 1 minute to elute RNA.
• Collect the eluted RNA in the collection tube.

Storage (as stated)

• Store extracted RNA at -70°C (subtitles) or possibly -20°C (speaker also mentions -20°C; captions appear conflicting).
• Core point: RNA is stored frozen until viral load testing.

Next stage mentioned

• After RNA extraction, the viral load is calculated from the extracted RNA.
• With the viral load result, the doctor can determine medicine dose.

Speakers / sources featured

• Speaker: Unspecified individual (host/presenter) addressing the audience for “Allerted Educare / alerted educare”.
• Organization/source named: Allerted Educare (YouTube channel/education brand).
• Reagent kit source named: GCC biotech kit.
• Equipment source named: Beckman Coulter centrifuge model Allegra 64R (cooling centrifuge).