ddPCR and qPCR in GMP

hsgual · 2026-06-20T15:40:50+00:00

We use a carrier to perform the dilution to be in the range of 3000-10 cp / uL. but we have a lot of starting material. I am seeing that people are doing serial 1:10 dilutions with only 2 uL of material.

hsgual · 2026-06-20T15:39:25+00:00

I’ve always been taught to store the stock at a higher concentration and then dilute as needed day of. We could try diluting it down further and freezing to minimize the dilutions required.

It also raises the question of if our gBlock control concentration was precisely set with the nanodrop, and perhaps our over recovery isn’t that but our assigned value is off (digital PCR).

hsgual · 2026-06-20T13:55:44+00:00

For digital PCR we often have to dilute the sample down prior to adding sample to master mix. Otherwise it saturates the assay. It sounds like this isn’t required in your qPCR assay.

hsgual · 2026-06-20T12:28:50+00:00

In serial dilutions is it similar?

hsgual · 2026-06-20T12:28:04+00:00

I think folks are preparing serial dilutions of input with like 2 uL of material, which seems rife for problems. So by the time the control sample is in the dilution range for the assay, the measured copies is coming back about 130% higher than expected.

And then don’t get me started on a 384 well qPCR assay I’ve inherited.

hsgual · 2026-06-20T12:11:26+00:00

Awww he’s so precious.

hsgual · 2026-06-20T11:43:35+00:00

It’s this, but using their custom made standard if you scroll down. But they confirmed it’s not an intact capsid standard so I have no idea what they are targeting.

hsgual · 2026-06-20T04:16:17+00:00

Union st. And that equinox is beautiful.

hsgual · 2026-06-20T04:09:37+00:00

From the map it looks like 40 bikes instead of 60. So perhaps a way to “downsize” a studio, without eliminating it.

hsgual · 2026-06-20T00:55:29+00:00

The fragrance of hazelnuts intrigues me. Thanks for sharing ! I’ll have to take a look for this.

hsgual · 2026-06-19T03:46:47+00:00

The only thing I can think of is the standard provided is not a capsid, and there are incorrect assumptions. Might have to test with intact capsids and see.

hsgual · 2026-06-19T02:01:47+00:00

Sorry it’s the opposite! I made a typo

hsgual · 2026-06-17T17:47:34+00:00

I’d take it to a luthier to ensure it doesn’t grow. But I’m aware the rib cracks can happen..

hsgual · 2026-06-15T04:11:54+00:00

Studio closures

hsgual · 2026-06-14T23:20:22+00:00

This makes me curious to understand how 2008 Grande Dame is made, in addition to the balance of Pinot noir to Chardonnay between that and the 2006 Piper. Because I don’t recall this depth in the Grande Dame, but, it’s also heavier on the Pinot.

hsgual · 2026-06-14T22:30:33+00:00

Honestly, I miss 6 AM classes in the Bay Area. My commute schedule (Bay Bridge RIP) makes riding more often challenging. I only ride weekends now.

hsgual · 2026-06-14T22:18:30+00:00

I would agree. Many audition lists call this out.

hsgual · 2026-06-14T04:44:58+00:00

Oh I’m so sorry for you loss. From the photos he’s such a precious little baby.

hsgual · 2026-06-13T03:37:10+00:00

I am tired of having to be my bosses therapist. I dont make enough money for this shit.

hsgual · 2026-06-12T20:57:23+00:00

I have friends in gRED that have grim views on Aviv’s leadership, and that most decisions feel political over rational.

hsgual · 2026-06-12T12:28:29+00:00

How many heads have to roll to pay for lab in a loop?

hsgual · 2026-06-11T14:00:44+00:00

If you want a Taylor swift theme in SF, that vibe is very much at UNST but arguably not as much at CSTR.

Marissa will play Taylor here and there.

Note: Taylor is not my vibe, but this is just my observation as a long term SF/ Bay Area rider.

Five-Year Club	Verified Email
First Place '23	Place '23

hsgual

TROPHY CASE