If you have been reading about RP-HPLC and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-08-31. Numbers and descriptions here follow the published literature rather than marketing material.
Thymosin alpha 1 is a short peptide first isolated from bovine thymus tissue in the early 1970s during fractionation work aimed at identifying factors that influence T cell development. It belongs to a family of acidic thymic peptides, and the original preparations contained several components that were later separated by chromatography. The compound is now produced synthetically rather than extracted from tissue, which removes batch variability tied to animal sourcing. Researchers describe it as an immunomodulatory peptide because laboratory studies show effects on several cell types of the innate and adaptive immune systems.
The molecule consists of 28 amino acid residues with an acetyl group attached to the N-terminal serine. Its sequence is acidic overall, with several glutamic and aspartic acid residues distributed along the chain and no cysteine, so disulfide bridges do not form. The peptide carries a net negative charge at physiological pH. Because the N-terminus is blocked, the intact molecule resists degradation by many aminopeptidases, which contributes to its stability in biological fluids.
Long-term storage is generally at minus twenty degrees Celsius or colder, preferably desiccated and protected from light. Lyophilized material is more stable than reconstituted solution, which degrades faster at room temperature. Stability depends on pH, ionic strength, and the presence of oxidising agents. Published stability data for the peptide are limited, so storage claims in catalogues should be treated as general guidance rather than measured guarantees. Freeze-thaw cycles are kept to a minimum.
Identity and purity are normally confirmed by reversed-phase high-performance liquid chromatography and mass spectrometry. The expected mass for the acetylated 28-residue peptide is close to 3108 daltons, and a mass shift indicates a modification or truncation. Peptide mapping after enzymatic digestion can resolve sequence-level questions. Counter-ion content, water content, and residual solvents are separate quality attributes that a certificate of analysis may or may not report. Aggregation is monitored by size-exclusion chromatography when relevant.
Thymosin alpha-1 is supplied as a lyophilized powder in most research settings. The solid dissolves readily in water and in common aqueous buffers, and it is typically reconstituted shortly before use. Solutions are clear and colourless at ordinary working concentrations. Because the peptide is hygroscopic, weighing and reconstitution are usually performed with minimal exposure to ambient air. Aliquots are prepared to avoid repeated freeze-thaw cycles, and working solutions are kept cold.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Acetylated peptide | N-terminal acetyl group blocks aminopeptidase attack |
| Residue count | 28 amino acids | Matches the N-terminus of prothymosin alpha |
| Molecular mass | About 3,108 Da | Value for the free, unmodified peptide |
| Isoelectric point | Approximately 4.2 | Acidic; net negative charge at neutral pH |
| Encoding gene | PTMA | Human gene for the precursor protein |
Thymosin alpha 1 is approved as a medicine in several countries, including Italy and China, for indications such as chronic hepatitis B and as an immune adjuvant. It is not approved by the United States Food and Drug Administration as a therapeutic product. In research settings the peptide appears in studies of sepsis, vaccine response, and oncology support, often with mixed or inconclusive results. The evidence base is uneven, and reviews note that many trials were small. Regulatory status therefore differs widely between jurisdictions.
Thymosin alpha 1 is a synthetic 28-amino-acid peptide first isolated in 1966 from thymosin fraction 5, a bovine thymus extract. Its chain begins with an acetylated serine residue and ends with asparagine. The native peptide carries a molecular mass near 3,108 daltons. Researchers classify it as an immunomodulatory agent rather than a hormone with a single endocrine target. Early work framed it as a thymus-derived factor that supports T-cell maturation. The synthetic form used in research and clinical products matches the natural sequence.
Immune signaling studies link thymosin alpha 1 to Toll-like receptor pathways, particularly TLR2 and TLR9, on dendritic cells and other antigen-presenting cells. Activation of these receptors promotes maturation of T cells and increases natural killer cell activity. The peptide shifts cytokine output toward a T helper 1 profile, raising interferon gamma and interleukin 2 while modulating interleukin 10. Whether these effects translate into clinical benefit for any specific disease remains a subject of debate. Reported outcomes vary across trials and populations.
Reverse-phase high-performance liquid chromatography is the standard technique for assessing purity and concentration, because the peptide's hydrophobicity allows clean separation from related impurities. Mass spectrometry confirms molecular identity and detects sequence errors or truncations. Amino acid analysis and peptide mapping supply additional structural confirmation when required. Chromatographic purity values reported on certificates of analysis describe the proportion of the main peak and do not by themselves establish biological activity.
Like most short peptides, thymosin alpha-1 is susceptible to hydrolysis under strongly acidic or basic conditions and to oxidation when exposed to air over long periods. The acetylated amino terminus blocks one common degradation route, which contributes to the molecule's relative robustness in solution. Lyophilized material generally retains potency for extended periods when kept cold and dry. Once reconstituted, aqueous solutions are less stable and are typically used within a defined window rather than held indefinitely at ambient temperature.
Laboratory work indicates that the peptide acts on cells of both the innate and adaptive immune systems. Reported effects include signalling through Toll-like receptors on dendritic cells, enhanced T-cell maturation, and increased natural killer cell activity. These actions are described largely from cell-culture and animal experiments, and the precise receptor-level events remain incompletely defined. Studies in humans have generally measured immune markers rather than a single defined molecular target. The resulting picture remains partly descriptive.
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Results across trials have been mixed, and several studies were small or conducted under differing protocols. Regulatory status varies by country, and the compound is not approved in every jurisdiction where it is studied. Evidence for any single indication should be read with attention to sample size and endpoint choice.
Thymosin alpha-1 is a 28-residue peptide first isolated from thymus tissue in the 1970s. It corresponds to the N-terminal portion of thymosin beta-4, from which it is cleaved in vivo. The peptide carries an acetyl group at its N-terminus, a modification that affects its charge and stability. Synthetic material produced by solid-phase peptide synthesis is chemically identical to the natural fragment and is the form used in research and clinical studies.
Laboratory supplies of the peptide usually arrive as a lyophilized powder in sealed vials. The powder is hygroscopic, so a vial should be allowed to reach room temperature before it is opened to prevent condensation on the contents. Weighing and transfer are best performed in a low-humidity environment with clean tools. Once dissolved, the solution should be mixed gently rather than vortexed, because foaming and shear can reduce recovery of the peptide.
Storage recommendations center on low temperature, dryness, and protection from repeated freezing and thawing. The intact powder is commonly held at 20 degrees below zero Celsius or colder, while a working solution is divided into single-use aliquots to limit freeze-thaw cycles. Buffered saline or phosphate-buffered saline at neutral pH is frequently used as a diluent. Light sensitivity is not well documented, yet amber vials or foil wrapping are common practice for long-term storage of peptide stocks.
== Clinical development == The precursor molecule to BOLD-100, KP1339 was tested in a Phase 1 monotherapy clinical trial in heavily pretreated patients with advanced cancers. In this dose escalation study, KP1339 was administered to 46 patients with doses ranging from 20 mg/m2 to 780 mg/m2. KP1339 was well tolerated, with the treatment-emergent adverse events occurring in >20% of patients being nausea, fatigue, vomiting, anaemia and dehydration. These adverse events were mainly grade 2 or lower. In the 38 efficacy-evaluable patients, nine patients achieved stable disease and 1 patient had a durable partial response. 625 mg/m2 was determined to be the recommended Phase 2 dose. BOLD-100 is being tested in a Phase 1b/2a clinical trial in combination with the chemotherapy regimen FOLFOX (5-fluorouracil, leucovorin, and oxaliplatin) for the treatment of gastrointestinal cancers, including gastric, pancreatic, colon and bile duct cancer. This trial includes a dose escalation phase followed by a cohort expansion with 117 patients enrolled. Interim data presented at ASCO GI in January 2024 showed that BOLD-100 + FOLFOX was active and well-tolerated treatment in a heavily pre-treated Stage IV mCRC study population with 36 patients. Progression Free Survival, Overall Survival, and Objective Response Rate demonstrate significant clinical benefit and improvement over the currently available therapies, with minimal treatment emergent neuropathy or significant toxicities.
A pharmacy (also known as a chemist in Australia, New Zealand and the British Isles; or drugstore in North America; retail pharmacy in industry terminology; or apothecary, historically) is where most pharmacists practice the profession of pharmacy. It is the community pharmacy in which the dichotomy of the profession exists; health professionals who are also retailers. Community pharmacies usually consist of a retail storefront with a dispensary, where medications are stored and dispensed. According to Sharif Kaf al-Ghazal, the opening of the first drugstores are recorded by Muslim pharmacists in Baghdad in 754 AD.
Different countries have different regulatory requirements and enforcement abilities. An estimated 40% of all clinical trials now take place in Asia, Eastern Europe, and Central and South America. "There is no compulsory registration system for clinical trials in these countries and many do not follow European directives in their operations", says Jacob Sijtsma of the Netherlands-based WEMOS, an advocacy health organisation tracking clinical trials in developing countries. Beginning in the 1980s, harmonization of clinical trial protocols was shown as feasible across countries of the European Union. At the same time, coordination between Europe, Japan and the United States led to a joint regulatory-industry initiative on international harmonization named after 1990 as the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) Currently, most clinical trial programs follow ICH guidelines, aimed at "ensuring that good quality, safe and effective medicines are developed and registered in the most efficient and cost-effective manner. These activities are pursued in the interest of the consumer and public health, to prevent unnecessary duplication of clinical trials in humans and to minimize the use of animal testing without compromising the regulatory obligations of safety and effectiveness."
== History of the field == An early time-of-flight mass spectrometer, named the Velocitron, was reported by A. E. Cameron and D. F. Eggers Jr, working at the Y-12 National Security Complex, in 1948. The idea had been proposed two years earlier, in 1946, by W. E. Stephens of the University of Pennsylvania in a Friday afternoon session of a meeting, at the Massachusetts Institute of Technology, of the American Physical Society. In 1953, Stephens reported an improved design that could resolve the cyclic hydrocarbons up to cycloheptane using an instrument constructed at the Esso Laboratories, reporting that the main limitations were "primarily in sensitivity and outgassing of the ion source." By 1955, compounds with masses over 100 g/mol could be resolved.
Sources: en.wikipedia.org
While under TBN, the Bakkers moved to Charlotte, North Carolina, where in May 1973 they launched an east coast version of Praise The Lord under TBN's umbrella. Less than a year later the Bakkers formed their own non profit organization, registered the PTL trademark, left the umbrella of TBN and the Crouches, and continued their show on 36 WRET Charlotte, 16 WGGS Greenville, South Carolina, and a few other stations. In 1975, they nationally debuted their own late night-style talk show, known as The PTL Club. Bakker founded the PTL Satellite Network in 1974, which aired The PTL Club and other religious television programs through local affiliates across the U.S.
The fusion of droplets with different contents can also be exploited for reagent addition. Electro-coalescence merges pairs of droplets by applying an electric field to temporarily destabilize the droplet-droplet interface to achieve reproducible droplet fusion in surfactant-stabilized emulsions. Electro-coalescence requires droplets (which are normally separated by the continuous phase) to come into contact. By manipulating droplet size in separate streams, differential flow of droplet sizes can bring droplets into contact before merging. Another method for facilitating droplet fusion is acoustic tweezing. While droplets are flowing in microfluidic channels, they can be immobilised using an acoustic tweezer based on surface acoustic waves. Once a droplet is held with the acoustic tweezer, consecutive droplets collide into it and fusion takes place.
At the age of 13, Boyd Orr won a bursary to Kilmarnock Academy, a significant achievement as such bursaries were then rare. The new school was some 20 miles (32 km) from his home in West Kilbride, but his father owned a quarry about two miles (3 km) from the academy, and John was provided with accommodation nearby. His family cut short his education at the academy because, at the expense of his school attendance, he was spending time with the quarry workers, who let him work the machinery, and from whom he picked up a "wonderful vocabulary of swear words". After four months he returned to the village school in West Kilbride where he continued his education under the inspirational tutelage of Headmaster John G. Lyons. There he became a pupil teacher at a salary of £10 for the first year, and £20 for the second. This was a particularly demanding time for the young Boyd Orr, as in addition to his teaching duties, and studying at home for his university entrance and teacher-training qualifications, he also had to work every day in his father's business.
The first national team was in the kingdom that existed between the two world wars. The Football Federation of what was then the Kingdom of Serbs, Croats and Slovenes was founded in Zagreb in 1919 under the name Jugoslavenski nogometni savez (and admitted into FIFA), and the national team played its first international game at the Summer Olympics in Antwerp in 1920. The opponent was Czechoslovakia, and the historic starting eleven that represented Kingdom of SCS on its debut were: Dragutin Vrđuka, Vjekoslav Župančić, Jaroslav Šifer, Stanko Tavčar, Slavin Cindrić, Rudolf Rupec, Dragutin Vragović, Artur Dubravčić, Emil Perška, Ivan Granec, and Jovan Ružić. They lost by a huge margin 0–7, but nonetheless got their names in the history books.
== Education and early career == Tew earned a Bachelor of Science in Microbiology/Genetics from the University of Wales, Swansea in 1973 and a PhD in Biochemical Pharmacology from the University of London, where he also received postdoctoral training in 1976. He served as the Head of the Basic Pharmacology Program at the Lombardi Cancer Center from 1982 to 1985, when he became a member and later Chairman of Pharmacology at the Fox Chase Cancer Center. Concurrently, he worked as an Adjunct Associate Professor of Pharmacology at the University of Pennsylvania until 1990 and was awarded his DSc from the University of London in 1995.
Sources: en.wikipedia.org
Making Nylon, Bob Burk, CHEM 1000, Carleton University, Ottawa, Canada on YouTube Polyamide Nylon Plastic Joseph X. Labovsky Collection of Nylon Photographs and Ephemera Science History Institute Digital Collections. (High-resolution scans of nylon-related photographs and ephemera collected by Joseph X. Labovsky, a lab assistant to Wallace Carothers, during the early stages of nylon development and production at DuPont).
A script version of the words Dunkin' Donuts was filed on March 31, 1955, and registered on February 2, 1960. A later logo was for a drawing and word logo depicting a figure with a doughnut for a head and a coffee cup and doughnut body wearing a garrison cap, with Dunkin' emblazoned on both the coffee cup and cap. The design was rendered primarily in yellow and brown. The logo was applied for on June 23, 1958, registered on May 23, 1961, and put into use on July 1, 1964. In 1966, the company began using a hot pink color for its branding and used a logo showing a stylized coffee cup with the company's name rendered on one line as a circle, evoking a doughnut dunking into the cup. In 1980, bright orange was added to the hot pink. As of 2014, the logo was a variation of the logo that has been in use since 1980: an all-capitals rendering of the words Dunkin' Donuts (Dunkin' in orange, Donuts in pink) in a thick, Frankfurter typeface with a coffee cup outlined in brown with a "DD" monogram. In September 2018, the company announced that it would shorten its name to Dunkin', with a wider roll out beginning in January 2019. The company acknowledged "Dunkin'" was already a common name for the chain among customers and in its marketing (including the slogan "America Runs on Dunkin'"), and that the rebranding would reflect the chain's continuing shift towards being a "beverage-led" brand at a time when consumers have shown a preference for healthier trends and options as they eat fewer doughnuts. While stores in the U.S.
Anatoly Lunacharsky became the first People's Commissar for Education of Soviet Russia. In the beginning, the Soviet authorities placed great emphasis on the elimination of illiteracy. All left-handed children were forced to write with their right hand in the Soviet school system. Literate people were automatically hired as teachers. For a short period, quality was sacrificed for quantity. By 1940, Stalin could announce that illiteracy had been eliminated. Throughout the 1930s, social mobility rose sharply, which has been attributed to reforms in education. In the aftermath of World War II, the country's educational system expanded dramatically, which had a tremendous effect. In the 1960s, nearly all children had access to education, the only exception being those living in remote areas. Nikita Khrushchev tried to make education more accessible, making it clear to children that education was closely linked to the needs of society. Education also became important in giving rise to the New Man. Citizens directly entering the workforce had the constitutional right to a job and to free vocational training. The education system was highly centralized and universally accessible to all citizens, with affirmative action for applicants from nations associated with cultural backwardness. However, as part of a general antisemitic policy, an unofficial Jewish quota was applied in the leading institutions of higher education by subjecting Jewish applicants to harsher entrance examinations.
Extreme exercise can make capillaries vulnerable, with a breaking point similar to that of collagen. Capillary permeability can be increased by the release of certain cytokines, anaphylatoxins, or other mediators (such as leukotrienes, prostaglandins, histamine, bradykinin, etc.) highly influenced by the immune system.
space. The boundaries of the shaded regions in the figure are the boundaries of stability in the two directions (also known as boundaries of bands). The domain of overlap of the two regions is the trapping domain. For calculation of these boundaries and similar diagrams as above see Müller-Kirsten.
Sources: en.wikipedia.org
Thymosin fraction 5 is a mixture of many peptides obtained from thymus tissue, while thymosin alpha 1 is a single defined 28-residue molecule. The two names appear together in older literature because the purified peptide was first obtained from that mixture.
The precursor, prothymosin alpha, is encoded by the PTMA gene in humans. The 28-residue peptide corresponds to the N-terminal segment released from that larger protein.
It is produced as a fragment of prothymosin alpha and is present in many tissues. Circulating concentrations are low, which makes routine measurement difficult.
Lyophilized powder is normally kept at minus twenty degrees Celsius or below, in a sealed container, desiccated and away from light. Reconstituted solutions are less stable and are usually refrigerated and used quickly. Repeated temperature cycling should be avoided.