Peptide Critic Community

I use it specifically for MOTSc and ISR went away - I can't say for certain it was that but no more ISR after starting with the Hospira Sodium Bac. Can actually be used for most peptides but not all. Our bodies like it because it more closely aligns.

@MJ227 That really sucks... very disappointing.

@bfuller IMO - you're much better off with Flawless Compounds - love buying from them! From my experience (which is documented in various places on this forum), NEXAPH gets a BIG thumbs down from me (among other fingers I could use).

I agree - they have been Flawless with me. Just placed 2 orders this week. Already received one and get the one I placed today on Monday! Product/service/info/packaging has been second to none.

@MJ227 Fair enough. Always seems to be easier to pay than the other way around.

@MJ227 Well at least you got a refund which is more than I can say about Nexaph and my dissatisfaction. I had a product issue with them that has been well documented on this forum with pictures etc. I was completely blown off by Nexaph and basically told it was my fault for ordering their inferior and inconsistent product. I had also requested a refund or replacement and was denied flat out. Cain never ever once got on here to address anything I had to say - I guess he was too good or too busy to talk with a customer. Thankfully Jeff stepped forward to help me resolve the issue - I can't say enough good things about him and this forum to let us air our grievances.

I'm impressed by Jamie, one of the owners of Flawless coming on this forum and communicating with you and everyone else to help resolve any issue - that is not an easy thing to do. I'll continue to order from Flawless (I have placed numerous orders with them and have never had an issue with any peptide, packaging, quality, communication, ship time, accuracy, etc. - they have been "Flawless" with me) and continue recommending them to others for their peptide researching.

Also, fake reviews are a double edged sword... there can be scum bags (perhaps paid by a competitor) to leave fake "bad reviews" to try and torpedo a great company. Happens ALL the time on Amazon.

Well... for what it's worth. I placed a review about Flawless compounds over a month ago and completely concur with this review. Placed several orders... all shipped within a day and received within a couple of days. No errors. Quality seems amazing and I'm totally impressed with Flawless.

@Shaqdiesel Thank you!

I tried 2mg for 30 days and didn't do a thing. I'll be trying Epithalon next month and maybe those 2 together at some point.

@Nuncles IMO the v3.5 feels just a bit sturdier than the V4. V3.5 is a bit shorter. The clear piece screws on w/V3.5 instead of clicking into place on the V4 - this is a very subtle comment but one that is important to me and that is the clear plastic 3mL vial pc on the V4 clicks into place showing the scale of how much peptide is left right in line with the dial # which makes it easier reference for me. Mechanism is about the same. Can't go wrong with either but my personal preference is the V4.

BTW... also got some V2 pens for my wife because she likes the colors but I do not like those as well - they just feel "cheaper" to me. I do use Xulin for TRT (Blue) & Reta (Red) which are very classy pens - makes me feel special using those. But still through it all - my preference is the silver V4 - great great pen.

I've tried all the pens on here except the gansulin & v1. I like the v4s best but you can't go wrong with any that Jeff sells here. Plus at 60 units per pen they fit in some real nice cases I bought on ETSY. If you get the longer pens at 80 units - they don't fit the case - too long.

Yeah thanks... Jeff stepped up and was a real savior in the situation which I greatly appreciate and why I'm such a fan of him and his site.

My whole contention with Nexaph was about consistency within the same batch (all small pucks - fine, all large pucks - fine, but an obvious mish mash of contents - not good IMO - indicative of process issues)... After Jeff's lab analysis of the peptide content, that size didn't matter for that aspect - I was relieved for anyone buying from Nexaph but I will never buy from them again and here's why.

I did a deep dive on the manufacturing process of peptides and inconsistencies that present within the same batch and what issues that could pose to the quality of the product. Needless to say - it wasn't good which I knew would be the case. And if a company screws a batch up (meaning the batch was NOT produced according to spec) there IS/was a manufacturing problem and a quality issue whether becoming apparent now or sometime in the future and is NOT just a cosmetic thing.

IMHO Nexaph had NO business/integrity dumping that product on an unsuspecting public - naive me. They should have at a minimum been willing to exchange the product or provide a refund upon request once I brought the obvious inconsistency to their attention which they were COMPLETELY unwilling to do - made me feel like - sorry loser you should have known better before making the purchase.

So, doing my civic duty, I'm just trying to inform the public of the company's actions and apparent core value of profit ahead of quality product before making a purchasing decision. There are plenty of fans of Nexaph out there (also plenty of alternative vendors) and I wanted to be one but was given a different path by them. BUYER BEWARE - don't think it can't happen to do. Their behavior/arrogance in this situation is the type of behavior/thinking that can (and hopefully would never) lead to worse outcomes in the future - I've seen it happen with plenty of companies. In their defense, they eventually got back to me, denied any request I had, and defended themselves in the situation. So, I've moved on to other vendors at half the cost or less and will continue to inform the public of my experience.

I don't know the answer to your specific question but you bring up a much bigger question overall for the peptide world IMHO and something perhaps Jeff can address in one of his blog posts that I don't think he addressed in "size doesn't matter." But rather, does filler even matter?

So I asked perplexity AI the importance of fillers in the lypophilization manufacturing process for peptides and here is what I got that maybe helps:

"Fillers (excipients) are critical in peptide lyophilization because they provide a physical matrix and chemical protection that preserves peptide structure, potency, and handling properties during freeze drying and storage.

What fillers do in peptide lyophilization

During lyophilization, peptides alone often form fragile, glassy films or “crusts” that can crack, collapse, aggregate, or cake, leading to loss of activity and poor reconstitution. Adding excipients—typically sugars, polyols, amino acids, and buffers—creates a more robust solid matrix that supports the peptide and controls how ice forms, how the cake dries, and how the final plug behaves over time.

Key functional roles
• Structural/bulking matrix: Bulking agents such as mannitol, sucrose, lactose, or glycine increase solid content so you get a stable, self supporting cake rather than a thin film. This bulking prevents collapse and makes the product mechanically robust during shipping and handling.
• Cryo and lyo protection: Sugars like trehalose and sucrose act as cryoprotectants and lyoprotectants, interacting with peptide backbones and side chains to reduce denaturation and aggregation during freezing and drying. They help replace water’s hydrogen bonds and modulate glass transition temperature (Tg′), which is central to setting a safe primary drying temperature.
• Improved reconstitution: A well designed filler system creates a porous, sponge like cake that takes up diluent rapidly and dissolves uniformly. Without fillers, peptide solids can form dense, glassy “bricks” that take much longer to go into solution and may leave visible particulates.
• Protection from oxidation and moisture: Some excipients form a barrier that slows oxygen diffusion and moisture uptake, both of which drive peptide degradation pathways like oxidation, deamidation, and hydrolysis. Proper excipients also help maintain low residual moisture after secondary drying, extending shelf life.
• pH and tonicity control: Buffers (e.g., phosphate systems) maintain pH in the optimal stability range for the specific sequence, while salts (NaCl, dextrose) adjust tonicity when the lyophilized peptide will be used in cell based or in vivo studies.

Common filler categories and examples
• Bulking agents: Mannitol is highly favored because it tends to crystallize and produce an elegant, rigid cake with minimal interaction with many peptides. Alternatives like sucrose or lactose can be used where mannitol crystallization behavior is undesirable, or where more amorphous structure is needed.
• Cryo/lyoprotectants: Trehalose and sucrose are classic choices because they are chemically stable, glass forming, and have extensive data supporting their ability to preserve protein/peptide conformation. Glycerol and similar polyols may be used at the liquid stage as cryoprotectants but are less typical in final solid therapeutic formats.
• Buffers and stabilizers: Phosphate buffers are common, but choice depends on sequence specific pH stability and compatibility with other excipients. Surfactants (e.g., polysorbates) are more relevant for proteins but may be included for peptide formulations sensitive to interfacial stress.
What happens if you omit fillers
• Loss of biological activity: Without a protective excipient system, peptide chains are more exposed to freeze concentration, pH shifts, and interfacial stresses, increasing risks of aggregation, misfolding, or chemical degradation during the cycle.
• Poor cake and handling: “Naked” peptides can yield shrunken, cracked, or collapsed plugs that are fragile, tend to shed particles, and can reconstitute poorly with visible clumps or incomplete dissolution.
• Shorter shelf life: Higher residual moisture, greater oxygen access, and an unstable amorphous matrix accelerate degradation, so potency drops faster in storage compared to optimized formulations with appropriate excipients.
Practical implications for research peptides

For research grade lyophilized peptides, vendors typically include small amounts of bulking agents (commonly mannitol, trehalose, or sucrose) even when labels don’t emphasize it, precisely to ensure stable cakes and reproducible reconstitution. These excipients usually have very low reactivity with peptides and have long histories of safe use in biopharmaceutical formulations."

And don't get me started on the whole Nexaph thing because I did a deep dive on variance in fill levels within a batch that Jeff was addressing... he wouldn't have liked the response so I stayed silent and let it alone.

I've noticed .9 sodium chloride with MOTS-c helped with my histamine reaction.

Couldn't tell you myself so I AI'ed it... The answer below. Don't know this to be true but here it is.

"PES earns the top spot for one primary reason: it has the absolute lowest protein/peptide binding rate of any syringe filter membrane material available. Here's the full breakdown: simsii

The Core Reason: Lowest Peptide Loss

PES is a naturally hydrophilic polymer, meaning it readily allows aqueous solutions to pass through without "grabbing" onto the peptide molecules in solution. Other membrane materials — even hydrophilic PVDF — have a slightly higher affinity for proteins and peptides, so a small but measurable amount of your peptide gets adsorbed into the membrane and never makes it to your vial. When you're working with expensive peptides at low concentrations, every unit matters. agilent

Additional Advantages of PES

Fastest flow rate — PES filters push liquid through quicker than PVDF or other membranes, which reduces the force needed on the plunger and lowers the risk of damaging the filter seal hplcvials
Chemically inert — it won't leach contaminants into your solution or react with standard reconstitution vehicles like bacteriostatic water simsii
Non-pyrogenic — certified free of pyrogens (fever-causing substances), which matters for anything you're injecting simsii
Transparent membrane — you can visually confirm the solution is passing through cleanly simsii
Industry standard for biologics — PES is the go-to membrane in biotech and pharmaceutical labs for sterilizing protein and peptide solutions, so it's extremely well-validated simsii

The Practical Takeaway

For your typical peptide reconstituted in BAC water or sterile water, PES simply checks every box: lowest peptide loss, fastest flow, no contamination risk, and proven sterile filtration at 0.22 µm. Hydrophilic PVDF is excellent but gets edged out on those first two points in pure aqueous applications. agilent

I've written plenty on here about my one and only experience with Nexaph - look it up if you want. Needless to say, I'll never do business with them again - 1 and done for me. If you have an issue with their product, don't expect any customer satisfaction from them - you'll be on your own. They are NOT here to serve that's for sure.

Here's a Grey Mkt source: Flourish Global Peptide discord link: https://discord.gg/8UHXgZBn

I have received some peptides form FGP (quick shipping, lots of selection, good prices) with no issues but can not speak to Cerebro... cost: $29 for a kit + shipping. Please do your own research to be comfortable ordering from Grey Mkt. I hope it helps.

I got that too and low and behold it did show up 2 days ago. So, keep the faith!