This is a working overview of drug affinity complex, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-07-20 and is reviewed periodically as new material appears.
CJC-1295 is a synthetic analogue of growth hormone-releasing hormone, built on the 29-amino-acid GHRH(1-29) fragment. Four substitutions distinguish it from the natural sequence: D-alanine at position 2, glutamine at position 8, alanine at position 15, and leucine at position 27. These changes reduce enzymatic cleavage and extend the peptide's persistence in circulation. The compound is discussed in two forms, one carrying a drug affinity complex and one without it.
The drug affinity complex is a maleimidopropionic acid group attached to a lysine side chain. It reacts with the free thiol of cysteine-34 on circulating albumin, forming a covalent bond. This conjugation keeps the peptide in the bloodstream and shields it from rapid renal filtration and proteolysis. Reported circulation half-lives for the albumin-bound form fall in the range of roughly six to nine days in early human studies.
Lyophilised powder is the usual supplied form. The material is hygroscopic, so vials are typically equilibrated to room temperature before opening in order to prevent condensation on the contents. Long-term storage is generally described at minus twenty degrees Celsius or colder, protected from light and moisture. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of soluble material. A reconstituted solution is considerably less stable than the dry powder and is normally kept refrigerated for short periods only.
Identity and purity are assessed mainly by reversed-phase high-performance liquid chromatography combined with mass spectrometry. The chromatographic separation resolves the target peptide from truncation products and from species carrying oxidised residues, while mass measurement confirms the expected molecular mass. Because the two common variants differ by roughly 280 daltons, a mass determination distinguishes them unambiguously. Purity is often quoted as a percentage of total peak area, although that figure depends on the detection wavelength and the integration method applied.
| Property | Value | Notes |
|---|---|---|
| Physical form | Lyophilized white powder | Supplied as a freeze-dried solid for research use |
| Molecular weight | Approximately 3,647 Da (DAC form) | Lower for the variant lacking the albumin-binding moiety |
| Solubility | Soluble in water and aqueous buffer | Typically dissolved in sterile or bacteriostatic water |
| Typical storage temperature | −20 °C or below | Dry powder, desiccated and protected from light |
| Common analytical method | Reversed-phase HPLC with mass spectrometry | Used for purity estimation and identity confirmation |
CJC-1295 is a synthetic peptide designed as a long-acting analogue of growth hormone-releasing hormone (GHRH). Its structure derives from the first 29 amino acids of native GHRH, a fragment often called GRF(1-29). Four substitutions were introduced to slow enzymatic breakdown and extend activity relative to the natural sequence. The compound was developed by ConjuChem as part of a broader effort to improve the pharmacokinetic profile of peptide hormones. It is studied in laboratory and clinical research settings rather than appearing as a naturally occurring substance.
Two related forms circulate in technical discussion under the same family name. The original version carries a drug affinity complex (DAC) that binds covalently to serum albumin after administration, and this linkage substantially extends circulation time. A second form, frequently written as modified GRF(1-29) or CJC-1295 without DAC, lacks that linker and clears much faster. The naming is a frequent source of confusion because the shorthand CJC-1295 can refer to either form depending on the source. Reports sometimes fail to specify which variant was studied.
CJC-1295 belongs to a family of synthetic peptides modeled on growth hormone-releasing hormone, the hypothalamic signal that prompts the pituitary to release growth hormone. The compound is built from the first twenty-nine amino acids of the natural human sequence, a fragment that retains full receptor binding capacity. Native growth hormone-releasing hormone is degraded quickly in circulation, so the fragment alone has limited practical value. Early work therefore focused on chemical modifications that preserve receptor binding while slowing enzymatic breakdown. The result is a molecule described in the literature as a long-acting analog of the natural hormone.
Two forms circulate under the CJC-1295 name, and they differ by a single appended group. The version without a drug affinity complex carries four substitutions along the peptide chain, including a D-alanine near the amino terminus and replacements at three other positions. These changes block the enzyme dipeptidyl peptidase IV and remove a methionine residue that is prone to oxidation. The modified fragment is frequently labeled MOD GRF 1-29. Naming conventions are inconsistent across informal sources, which is a common source of confusion.
=== Activation of emitters === The growth process of microneedles on emitters is termed ‘activation’. The tips of microneedles can provide high field strength for field desorption, and higher emission current can be obtained due to the increased emission area compared to metal tips. Some activation methods include high-temperature (HT) activation, high-rate (HR) activation, and electrochemical desorption. In the HT activation mode, a 10 μm tungsten wire is activated outside the mass spectrometer in a vacuum cell containing benzonitrile at a pressure of about 10−1 Pa. The tungsten wire serving as the field anode is then heated up to about 1500 K with direct current at a potential of about 10 kV with respect to a cathode. Carbon microneedles can be produced within 8-12 h. HR activation method is to reverse the polarity of the emitter and the counter electrode, which emits a strong electron current. The strong electron current results in the heating of the growing carbon needles and therefore the high rates of the needle growth. In the HR activation mode, needles of other metals (iron, nickel or cobalt) and of alloys can also be generated. Instead of carbon microneedles, metallic dendrites (mainly of nickel or cobalt) can be produced on thin wires through electrochemical desorption process. This method is even faster than HR method.
The histological and ultrastructural features of Ledderhose and Dupuytren's disease are the same, which supports the hypothesis that they have a common cause and pathogenesis. As with Dupuytren's disease, the root cause(s) of Ledderhose's disease are not yet understood. It has been noted that it is an inherited disease and of variable occurrence within families, i.e. the genes necessary for it may remain dormant for a generation or more and then surface in an individual, or be present in multiple individuals in the same generation with varying degree. There are certain identified risk factors. The disease is more commonly associated with:
Enzymatic specificity provides useful insight into enzyme structure, which ultimately determines and plays a role in physiological functions. Specificity studies also may provide information of the catalytic mechanism. Specificity is important for novel drug discovery and the field of clinical research, with new drugs being tested for its specificity to the target molecule in various rounds of clinical trials. Drugs must contain as specific as possible structures in order to minimize the possibility of off-target affects that would produce unfavorable symptoms in the patient. Drugs depend on the specificity of the designed molecules and formulations to inhibit particular molecular targets. Novel drug discovery progresses with experiments involving highly specific compounds. For example, the basis that drugs must successfully be proven to accomplish is both the ability to bind the target receptor in the physiological environment with high specificity and also its ability to transduce a signal to produce a favorable biological effect against the sickness or disease that the drug is intended to negate.
Sources: en.wikipedia.org
=== Background === In October 2008, Konstantin Kosachev, chair of the Russian State Duma Foreign Affairs Committee, said he supported the international investigation, but "a lot depends on who will enter this commission". In November 2008, Georgia called on the European Union to conduct an independent inquiry who was to blame for the conflict. An independent, international fact-finding mission headed by Swiss diplomat Heidi Tagliavini was established by the EU to determine the causes of the war. The commission relied on "recognised" experts. The commission was funded with €1.6 million. The report was published on 30 September 2009. According to the European Council on Foreign Relations, Russian information operations influenced the EU report. The report said it could not claim "veracity or completeness in an absolute sense", since "It incorporates what has been available to the Mission at the time of writing." The report could not give "total assurance that there are no mistakes or omissions".
=== Intravenous fluids === In those with poor tissue perfusion, boluses of isotonic crystalloid solution should be given. In children with more than 10–20% TBSA (Total Body Surface Area) burns, and adults with more than 15% TBSA burns, formal fluid resuscitation and monitoring should follow. This should be begun pre-hospital if possible in those with burns greater than 25% TBSA. The Parkland formula can help determine the volume of intravenous fluids required over the first 24 hours. The formula is based on the affected individual's TBSA and weight. Half of the fluid is administered over the first 8 hours, and the remainder over the following 16 hours. The time is calculated from when the burn occurred, and not from the time that fluid resuscitation began. Children require additional maintenance fluid that includes glucose. Additionally, those with inhalation injuries require more fluid. While inadequate fluid resuscitation may cause problems, over-resuscitation can also be detrimental. The formulas are only a guide, with infusions ideally tailored to a urinary output of >30 mL/h in adults or >1mL/kg in children and mean arterial pressure greater than 60 mmHg. While lactated Ringer's solution is often used, there is no evidence that it is superior to normal saline. Crystalloid fluids appear just as good as colloid fluids, and as colloids are more expensive they are not recommended. Blood transfusions are rarely required. They are typically only recommended when the hemoglobin level falls below 60-80 g/L (6-8 g/dL) due to the associated risk of complications.
=== Australia === A study by the Australian National University published in 2022 for Food Standards Australia New Zealand estimated there are 4.67 million cases of food poisoning in Australia each year that result in 47,900 hospitalisations, 38 deaths and a cost to the economy of $2.1 billion. A previous study using different methodology and published in November 2014, found in 2010 that there were an estimated 4.1 million cases of foodborne gastroenteritis acquired in Australia on average each year, along with 5,140 cases of non-gastrointestinal illness. The main causes were norovirus, pathogenic Escherichia coli, Campylobacter spp. and non-typhoidal Salmonella spp., although the causes of approximately 80% of illnesses were unknown. Approximately 25% (90% CrI: 13%–42%) of the 15.9 million episodes of gastroenteritis that occur in Australia were estimated to be transmitted by contaminated food. This equates to an average of approximately one episode of foodborne gastroenteritis every five years per person. Data on the number of hospitalisations and deaths represent the occurrence of serious foodborne illness. Including gastroenteritis, non-gastroenteritis and sequelae, there were an estimated annual 31,920 (90% CrI: 29,500–35,500) hospitalisations due to foodborne illness and 86 (90% CrI: 70–105) deaths due to foodborne illness circa 2010. This study concludes that these rates are similar to recent estimates in the US and Canada. A main aim of this study was to compare if foodborne illness incidence had increased over time.
Sources: en.wikipedia.org
The two share the same 29-amino-acid backbone. CJC-1295 carries an additional albumin-binding moiety that markedly extends its residence time in circulation, while the form without that moiety clears faster. Literature sometimes applies the name loosely to either variant.
It has not been approved by major regulatory agencies for any therapeutic indication. Material sold under this name is typically distributed for laboratory research only. Clinical use is not supported by large controlled trials.
Early human studies of the albumin-binding form reported circulation half-lives on the order of several days. The value depends on assay method and study design. Estimates for the form without the binding moiety are considerably shorter.
Chromatography reports how much material elutes as a single peak but does not confirm what that material is. Mass spectrometry supplies the molecular mass, which is characteristic of a given sequence and its modifications. Together the two methods support both a purity figure and an identity claim.