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Research on phospholipids exploded in the twentieth century as people dug into the role of these molecules in cell membranes and lung function. Scientists hunting for therapies in respiratory distress paid close attention to dipalmitoylphosphatidylglycerol, especially after surfactant therapy took off for preterm infants. DPPG started gaining profile as its properties became more understood—not just as a lung surfactant component but as a building block in model membrane systems. Over the decades, pharma companies sharpened production methods, and regulatory agencies like USP, BP, and EP set standards for purity and identity, so injectable-grade DPPG could meet the safety and performance bars for clinical settings. From bench work in university labs to full-scale manufacturing by pharmaceutical companies, DPPG’s journey shows how persistent scientific curiosity leads to real tools for treating patients and developing new types of drug delivery.
DPPG belongs to the family of glycerophospholipids. It shares some structural features with phosphatidylglycerol, but the presence of two palmitic acid chains gives DPPG unique physicochemical traits. Labs and manufacturers value pharma grade DPPG because of its ultra-high purity, low peroxide values, and heavy metal limits suitable for use in parenteral formulations. Each lot gets scrutinized for bacterial endotoxins, residual solvents, and exact fatty acid composition, because even traces of contamination can change how DPPG behaves in a drug or a test tube. Companies often supply DPPG as a fine white powder, sometimes as a sodium salt, sealed to keep out moisture and light. Strict controls on storage temperatures and shelf life protect its properties from degrading before it reaches the patient or the scientist.
DPPG’s real-world applications spring from its chemical makeup. It shows high hydrophobicity due to its double palmitic acid chains, which drive spontaneous assembly into bilayers and vesicles in water. Melting temperatures hover near 41°C, well above room temperature but just shy of body heat, giving DPPG bilayers a defined gel-to-liquid crystalline phase transition. In powder form, DPPG appears white or off-white, with tight moisture specifications ensuring its consistency between batches. A molecular weight around 776 g/mol, and a distinct sodium counterion that keeps the phosphate group ionized, define its behavior in water and organic solvents. Teams calibrate surface pressure, critical micelle concentration, and lipid packing density during formulation work because these variables control how DPPG interacts with proteins, drugs, and other lipids.
Each batch of DPPG shipping under BP, EP, or USP standards gets a certificate of analysis with fine-grained results for assay (usually above 98% pure by HPLC), pH in water, appearance, heavy metals (less than 5 ppm), and peroxide value (often below 5 meq/kg). Many companies add microbiological limits for total aerobic count and endotoxin, aligning with injectable drug requirements. Labels include full product names, batch numbers, manufacturing and expiry dates, and often storage instructions like “store at -20°C in a dry place.” Users find batch traceability and detailed impurity profiles crucial when submitting regulatory filings, since each deviation from spec can potentially impact product quality or patient safety.
Manufacturers synthesize DPPG using enzymatic or chemical routes, starting from glycerol and palmitic acid. Protection and deprotection of hydroxyl and phosphate groups, coupled with phosphorylation steps, yield the phosphatidylglycerol backbone. Sodium hydroxide or sodium carbonate ensures the final product carries the sodium salt form. Large-scale preparation prioritizes mild conditions to limit side reactions and hydrolysis, and uses column chromatography to strip away isomers and oxidation by-products. Final purification steps use rotary evaporation and lyophilization, locking in product stability. Each run gets rigorous in-process controls: pH, residual solvent analysis, and thin-layer chromatography verification for by-products. Only finished lots matching the pharmacopeial requirements reach the market, the rest get reprocessed or destroyed.
As both a reactant and a reagent, DPPG anchors many biophysical studies. Chemists can substitute headgroups or acyl chains to modulate surface charge or phase behavior. Others attach spin labels or fluorescent tags for tracking DPPG in imaging or spectroscopy studies. Mild oxidation and hydrolysis serve as stress tests for drug delivery research, showing how DPPG liposomes might break down in vivo. Pharmaceutical scientists sometimes pegylate or conjugate DPPG to boost circulation time in the bloodstream or target specific cells. Each chemical tweak gets tracked through NMR, mass spectrometry, and HPLC, because even subtle modifications can flip molecular behavior and change clinical outcomes.
DPPG goes by a handful of chemical synonyms in the scientific literature and on supply catalogues. Its IUPAC name—1,2-dipalmitoyl-sn-glycero-3-phospho-(1’-rac-glycerol) sodium salt—rarely shows up outside of formal documentation, but it reflects the precise stereochemistry and substitution pattern that matters for regulatory filings. In commercial language, you’ll find DPPG-Na, sodium dipalmitoylphosphatidylglycerol, or simply dipalmitoyl PG as shorthand, especially on shipping labels or research papers. This range of names can cause mix-ups or delays for buyers, making it important to verify exact CAS numbers and certificate details before placing orders.
Pharmaceutical-grade DPPG comes with safety data sheets detailing handling, storage, and disposal. Inhalation or injection in humans should happen under strict medical supervision, while lab staff rely on gloves, goggles, and ventilated hoods to prevent exposure to dust or degradation products. Manufacturers follow cGMP process controls, including HEPA-filtered air, filtered water, and validated cleaning protocols to avoid cross-contamination. Facilities log batch operations from raw material intake to final packaging, with electronic batch records and traceable QC reports. Audits inspect for compliance with the latest pharmacopeial updates, since minor oversights can lead to recalls or failed regulatory inspections. Even at the research stage, teams must manage DPPG as a potentially hazardous material, since inhalation of concentrated powdered phospholipids can cause bronchospasm or hypersensitivity in sensitive users.
Healthcare applications power demand for DPPG of pharma-grade purity. Neonatal surfactant replacement for preterm infants stands out. DPPG forms part of multi-lipid cocktails that reduce surface tension in underdeveloped alveoli, cutting risk of hypoxemia and death after premature birth. Beyond neonatology, DPPG sees use in model membranes for drug screening, vaccine delivery, and gene therapy particle creation. Because researchers can fine-tune liposome composition, DPPG shows up in slow-release injectable suspensions aimed at targeting cancers, autoimmune disease, and lung infections. Immunologists use DPPG in adjuvant systems that carry allergen extracts and antigens to kickstart protective immune responses without breakneck inflammation. Pharmaceutical scientists pick DPPG for stability studies, since its high phase transition temperature and uniform headgroup offer a reliable baseline for evaluating new lipid formulations.
Research on DPPG’s potential hasn’t slowed—even as established products reach clinical markets. Investigators explore how mixing DPPG with cholesterol or unsaturated phospholipids tunes drug release, uptake by macrophages, or immunogenicity. Mass spectrometry and cryo-electron microscopy map out how DPPG assemblies respond to changes in temperature, pH, or ionic strength. Biophysicists dig into how DPPG tolerates freeze-thaw cycles, so new vaccine technologies can ship worldwide without losing potency. Chemists pursue new synthesis routes that cut down waste, boost yields, and allow industrial-scale production without sacrificing quality. Research ethics boards keep a close eye on the use of DPPG in clinical trials, demanding robust animal and toxicology studies before first-in-human dosing gets approved.
Toxicologists weigh risks and benefits with every new batch of DPPG used in preclinical and clinical tests. Animal studies show DPPG rarely triggers acute toxicity when dosed intravenously or via inhalation at levels used for surfactant replacement. Still, repeated dosing and high concentrations can provoke immune responses, autophagy, or lipid embolism in animal models. Teams run genotoxicity, pyrogenicity, and irritation assessments before launch in humans. Long-term exposure studies track distribution and breakdown, reporting mainly hepatic and renal clearance, with low chance of bioaccumulation compared to other lipids. Industry partnerships support monitoring for adverse events in live clinical trials, and adverse event reports feed back into product labeling and usage guidelines to minimize harm in vulnerable populations, especially infants or the immunocompromised.
The next decade looks bright for DPPG. As biological drugs and vaccines grow more complex, demand for reliable, safe lipid excipients like DPPG will only intensify. Companies invest in greener synthesis pathways to cut environmental burdens and respond to new regulations on residual solvents and carbon intensity. Researchers chase new DPPG-based nanoparticles that can deliver RNA, DNA, or protein drugs directly to hard-to-treat tissues. Work continues to unravel the subtle effects DPPG exerts on immune signaling and cellular uptake, since these same effects could dictate both the safety and success rates of emerging therapies. The parallel rise of precision medicine nudges lipid manufacturers to offer custom blends and smarter lipid tracking, so each batch matches the needs of both regulators and patients. With the global push for access to cutting-edge respiratory treatments and safer vaccine carriers, DPPG looks likely to remain a tool scientists and clinicians lean on for decades.
Sodium dipalmitoylphosphatidylglycerol, or DPPG, isn’t an ingredient you see on most labels. This compound belongs to the phospholipid family, so it shares roots with the kind of fats our cells use to build their walls. DPPG carries a unique benefit: its structure stays robust under stress. Think of it as the reliable friend who keeps things in place during chaos. In medicine, that stability can mean the difference between a treatment that works and one that fizzles out in the body.
DPPG forms part of pulmonary surfactants, which give lungs the power to draw breath without collapsing. In premature babies, their lungs can miss that extra support. Doctors sometimes turn to surfactant replacement therapies to give newborns a greater shot at healthy breathing. DPPG stands out as a synthetic option that helps mimic nature’s version, especially in products meant for the tiniest patients. There’s a difference in how deeply I appreciate the value of something as basic as drawing breath after learning about how these molecules work together. The struggle and relief seen in neonatal intensive care units makes this less about science and more about possibility.
This phospholipid also plays a key role in drug delivery systems. Liposomes, which are tiny spherical sacs made from phospholipids, have become the darlings of advanced medicine. They protect sensitive drug molecules and help direct them where they’re needed most, so treatments waste less and help more. By choosing DPPG for the liposome’s makeup, researchers can adjust how the medicine interacts with cell walls, how it dissolves, and how much time it sticks around in the body.
We see the benefits of precise targeting in cancer treatment. Instead of flooding the body and creating harsh side effects, doctors use these drug carriers to concentrate medicine in the tumor. DPPG isn’t just a cog in a machine—it’s part of designing more humane treatment, answering families’ pleas for fewer side effects and better quality of life.
There’s growing interest in DPPG for new areas, too. Researchers have tried using DPPG in combination with antibiotics, either to boost the power of those antibiotics or to overcome tricky resistance. It all comes back to that property of interacting with cell membranes. In animal testing and early studies, DPPG-rich liposomes can break through bacterial defenses, carrying medicine where it counts. This is especially pressing with superbugs on the rise and older drugs losing their bite.
No scientific advance comes without hurdles. Costs for synthetic phospholipids can run high, and the methods to make them need careful monitoring. Consistency matters. Impurities could cause allergic reactions or make treatments less predictable. Companies and researchers will benefit from better synthetic methods or maybe even smarter ways to extract DPPG from natural sources. Expanding studies on safety profiles matters, too, especially for using these molecules with the most fragile patients or in long-term therapies.
My experience reading clinical stories and following drug approval processes pushes me to believe that solutions start with stubbornness—scientists and physicians keep digging at problems until they’re solved. Open collaboration between researchers, hospitals, and regulators will keep DPPG advances working in real-life medicine, not just the lab.
Dipalmitoylphosphatidylglycerol (DPPG), a phospholipid, steps into the spotlight when we talk about liposomal drug delivery or research on artificial lungs. It comes in different grades, each defined by a pharmacopeia: British Pharmacopoeia (BP), European Pharmacopoeia (EP), and United States Pharmacopeia (USP). The grade shapes which markets a product can reach, but more than that, it influences safety, performance, and reliability in the lab or at a patient’s bedside. That’s where the rubber meets the road for a clinician, a pharmacist, or anyone responsible for outcomes.
The differences between BP, EP, and USP grades don’t hide in the chemical structure—DPPG is DPPG. The secret lies in how strictly each grade sets its bar for allowable impurities, testing methods, and consistency from batch to batch. BP, EP, and USP develop their own rules focused on how the drug gets used in their regions. The stakes run high: a tighter impurity profile helps dodge unexpected side effects and ensures cleaner product lines.
From my experience working with pharmaceutical supply chains, these grades aren’t just bureaucracy. Labs run real risks using one country’s standard where another applies. Using BP grade in Europe or USP in the US isn’t just about legal clearance. If a batch drifts outside the specs laid out in that region’s pharmacopeia, a whole shipment gets scrapped—or sometimes, worse, a recall gets triggered. The cost of that mistake spirals out quickly.
Standards around identity testing, purity limits, and even packaging often surprise new researchers. EP and BP both aim for consistency across Europe, though their methods and tolerance levels sometimes carry subtle but meaningful differences. USP usually spells out more specific or regionally accepted analytical approaches. For DPPG, EP may set tighter controls over endotoxins due to the sensitivity of injectable drugs common in that area. USP, on the other hand, might call out heavy metal testing or tackle specific degradation products that show up in the North American supply chain.
Poor-grade DPPG doesn’t just mean “a bit more dirt.” Trace solvents or heavy metals left over from manufacturing have already drawn regulatory warnings in products using non-compliant phospholipids. In hospital settings, the payoff for strict grades comes every time someone avoids an allergic reaction or organ complication. Misreading these differences can mean missing out on the right market or putting patients in real danger. Working with a hospital compounding pharmacist, we once rejected an entire raw material order because the COA only covered BP specs, not EP or USP; regulatory scrutiny doesn’t cut corners for convenience.
One solution comes from talking directly with suppliers and demanding clear documentation. Certificates of Analysis need to show which pharmacopeia the batch suits, and batch-to-batch records back up every claim. Many teams benefit from running in-house QC on top of supplier tests, especially for high-stakes, high-cost actives like DPPG. Another approach? Pushing regulators for harmonization between pharmacopoeias, at least for core drugs like phospholipids, would save time and money industry-wide.
The difference between BP, EP, and USP goes deeper than paperwork—it shapes how research gets funded, drugs get approved, and patients get treated safely. Knowing those details puts quality in your control, not just in the hands of a distant manufacturer or a regulator’s checklist.
Dipalmitoylphosphatidylglycerol, known as DPPG, plays a key role in research and drug delivery. This compound helps build reliable liposomes, and researchers depend on its stable structure. Working with this material doesn’t feel like handling a regular chemical salt. I’ve seen how even a small slip in storage practice can impact results—phospholipids act as sponges for moisture and break down quickly when exposed to air, heat, or stray light.
Real-world challenges show up fast in any lab or production area. DPPG reacts with oxygen; tiny traces of water can turn it sticky. Colleagues tell stories about batches ruined just from a careless lid left open or a freezer cycle missed. If the powder clumps or the vial collects condensation, you can bet the next experiment ends in frustration. All those tiny changes, from failed hydration levels to new impurities, don’t just wreck a run—they put patients at risk later on.
DPPG holds up only at low temperatures. Most suppliers ship it on dry ice and recommend putting it straight into a -20°C or lower freezer. I’ve learned the hard way: never rely on a regular fridge, even for a few hours, unless you enjoy starting over. Temperature swings cause fats in DPPG to degrade, especially if the bag sees repeated thaw and freeze. Once you pop the seal, water vapor rushes in and starts a silent attack on the molecules.
Sunlight does more than fade a label. DPPG exposed to ultraviolet light sees its double bonds break, forming by-products that don’t make good pharmaceuticals. Oxygen pushes the same way, encouraging slow but steady breakdown. Working under dim light, with amber vials and inert gas like argon or nitrogen, keeps the quality up and the risk down. Opening a new pack always reminds me of handling fine chocolate in midsummer—too much air or light, and the end result tastes wrong.
Moisture may be the biggest enemy in any phospholipid lab. DPPG soaks up water from the air. Open a container on a humid day, and you’ll notice clumping soon after. This stuff is supposed to flow as a fine powder. Once wet, separating the useful material from the junk gets frustrating. Even worse, water kick-starts hydrolysis, splitting the fat chains and making unpredictable products. All the high-tech equipment in the world won’t bring it back to its original state.
Standard operating procedures keep labs out of trouble. DPPG stays safest in sealed, gas-flushed amber vials at -20°C or colder. I always label and date everything, then keep unneeded bottles out of the work area. If someone skips those habits, cleanup gets expensive—contaminated or spoiled materials can throw calendar schedules off by weeks. Using desiccators and single-use vials often costs a bit more, but it beats the risk of failed batches.
Those working with pharmaceutical ingredients know quality doesn’t just depend on chemical purity. It hangs on respect for details—temperature, light, airtight seals, and the patience to handle every step mindfully. DPPG rewards the careful, while shortcuts and sloppy handling punish everyone down the line, from scientists to patients.
Dipalmitoylphosphatidylglycerol, or DPPG, often enters the conversation in pharmaceutical labs and research meetings for a reason. As a negatively charged phospholipid, DPPG brings something special to liposome formulations that standard molecules like phosphatidylcholine do not. Its charge and structure change how a drug delivery system interacts with biological barriers—especially cell membranes. I remember a project where stable encapsulation of certain peptides kept failing. The moment DPPG entered the blend, things changed for the better, especially regarding particle stability and drug retention.
Researchers keep reaching for DPPG because it forms robust bilayers, and its charge can help target medicines where they're actually needed. For example, bacterial infections caused by resistant strains pose a real challenge. A liposome with DPPG can get closer to bacterial membranes because of electrostatic attractions, increasing the chances of the drug reaching its site of action.
Charge, stability, and biocompatibility don’t always show up in the same lipid. DPPG stands out. It creates a particular fluidity in liposome membranes, which helps with drug loading and controlled release. Take antibiotics like vancomycin or similar compounds. Free drug often fails where resistant bacteria grow biofilms. But once DPPG-based liposomes carry antibiotics, it can raise the odds of getting through those barriers.
Cancer treatment offers another example. Traditional chemotherapy goes everywhere in the body—hurting healthy tissue alongside cancer cells. Liposomes with DPPG sometimes show better tumor targeting by sticking to regions of lower pH and unique cell surfaces. In these ways, DPPG isn’t just another phospholipid. Scientists see its potential as a solution for therapies with tough delivery challenges.
Stability is crucial in the drug world. DPPG stands out for its ability to withstand temperature changes better than other lipids. Its transition temperature lands at about 41°C, making it suitable for storage and for use in medications kept at room temperature. I’ve seen stability concerns derail projects fast, so that higher melting point actually matters during real development—not just on paper.
DPPG earns its spot in research, but sourcing and cost deserve attention. Not every supplier delivers consistent quality, and DPPG often costs more than common lipids. For small-scale studies, this may get overlooked. Once the time comes for scale-up, cost can suddenly close doors. Regulatory expectations also add hurdles; DPPG must clear safety and purity checks, especially for injectable meds.
DPPG isn’t a fix-all. Its negative charge can sometimes trigger unwanted immune responses. Also, loading hydrophobic drugs into DPPG-rich liposomes requires some careful balancing of other lipids for optimal properties. I recall one test batch where adding too much DPPG made the liposomes unstable—finding the right mix of lipids (like cholesterol or phosphatidylcholine) solved the issue.
Researchers can blend DPPG with neutral or positively charged lipids to tweak the surface charge, aiming for reduced toxicity and better circulation times. Fine-tuning the particle size through extrusion and sonication sharpens targeting and reduces uptake by the immune system. These adjustments bring DPPG’s strengths into play without opening the door to unwanted side effects.
DPPG often shows up in promising studies for infectious diseases and cancer. Its unique properties give it a place in innovative therapies, despite the extra cost and sourcing challenges. Combining DPPG with other proven excipients, paired with careful batch testing, looks like a path forward for safer, more effective drug delivery.
Ultimately, DPPG keeps drawing attention because it solves problems many other lipids can’t. For anyone developing next-generation therapies or advanced drug carriers, giving DPPG a closer look could lead to answers where other approaches fall short.
Pharmaceutical grade Sodium Dipalmitoylphosphatidylglycerol, or DPPG, matters to more than just lab techs and chemists. It’s a backbone ingredient in specialized medicines, surfactants, and research. Purity tells people in the supply chain that a substance is not going to surprise them with unaccounted-for substances or weak performance. In this line of work, a 99% pure label isn’t an empty promise—it’s vital. The impurities can’t just be unknown smudges. Every trace amount of possible impurity deserves to be dug up and listed. Even 0.1% of the wrong contaminant changes results and threatens safety.
DPPG proves itself trustworthy through a certificate of analysis, or CoA. Ever since I started reading certificates, I’ve seen sloppy CoAs cause more headaches than small talk about the weather in a manufacturing plant. You want to know your lipids are pure, and you want to see that in clear numbers, not just buzzwords or vague categories.
Companies send out certificates documenting exact purity. For DPPG, the CoA should clearly show:
Pharmaceutical workers, pharmacists, and patients don’t ask for purity numbers out of habit—years of experience have shown what happens when shortcuts get taken. A ragged certificate, or missing chromatogram data, leads to products some feel uneasy giving to loved ones. This has taught me to always demand a complete and recent CoA with every shipment.
Some suppliers put marketing words first and test data second. Nobody expects perfection. But mistakes get caught less with confusing paperwork and inconsistent standards. Fact-based CoAs—backed up by routine audits, randomized sampling, and independent lab checks—make everyone’s life easier. The truth lands in the chemistry, not the branding.
Full traceability anchored by each CoA makes recalls (fortunately rare) clear and manageable. In every role I’ve held, the teams leaned on detailed certificates not just for compliance, but for comfort. Knowing exactly what goes into each batch—and seeing the proof—keeps the chain of trust solid from the factory to the patient’s bedside.
Stricter global standards aren’t a burden. They’re a common bond between users around the world. Smarter automation and instant digital certificates have upped the bar. Everyone can now check the data in real time, arguing less, trusting more.
If a batch of sodium dipalmitoylphosphatidylglycerol arrives with a vague or incomplete CoA, the best answer is to ask for full test results, not just summary lines. It’s not a hassle; it’s respect for the people counting on the medicine.
| Names | |
| Preferred IUPAC name | sodium 3-[(2R)-2,3-bis(hexadecanoyloxy)propoxy]-2-(phosphonooxy)propanoate |
| Other names |
1,2-Dipalmitoylphosphatidylglycerol sodium salt DPPG-Na Sodium 1,2-dipalmitoyl-sn-glycero-3-phosphoglycerol Dipalmitoylphosphatidylglycerol sodium salt DPPG sodium salt |
| Pronunciation | /ˌsoʊdiəm daɪˌpælmɪˌtɔɪlfɒsˌfeɪtɪdilˌɡlɪsəˈrɒl/ |
| Identifiers | |
| CAS Number | 2438-32-6 |
| Beilstein Reference | 3859350 |
| ChEBI | CHEBI:76332 |
| ChEMBL | CHEMBL2088881 |
| ChemSpider | 21542470 |
| DrugBank | DB11107 |
| ECHA InfoCard | 03eec64b-7158-438a-888a-0ada6379d89c |
| EC Number | EC 272-916-2 |
| Gmelin Reference | 77886 |
| KEGG | C04646 |
| MeSH | Dipalmitoylphosphatidylglycerols |
| PubChem CID | 16132553 |
| RTECS number | TC7352000 |
| UNII | 131V2V939Q |
| UN number | Not regulated |
| Properties | |
| Chemical formula | C40H78NaO10P |
| Molar mass | 797.1 g/mol |
| Appearance | White powder |
| Odor | Odorless |
| Density | 0.98 g/cm³ |
| Solubility in water | Insoluble in water |
| log P | -1.2 |
| Vapor pressure | Negligible |
| Acidity (pKa) | ~2.9 |
| Basicity (pKb) | base_pKb_15.5 |
| Magnetic susceptibility (χ) | \-95.5 × 10⁻⁶ cm³/mol |
| Refractive index (nD) | 1.470 |
| Dipole moment | 10.2 ± 0.3 D |
| Hazards | |
| Main hazards | Harmful if swallowed. Causes serious eye irritation. Causes skin irritation. |
| GHS labelling | GHS02, GHS07 |
| Pictograms | GHS07 |
| Hazard statements | H315, H319, H335 |
| Precautionary statements | Precautionary statements: P261, P264, P271, P272, P273, P280, P302+P352, P305+P351+P338, P308+P313, P332+P313, P333+P313, P337+P313, P362+P364, P501 |
| NFPA 704 (fire diamond) | NFPA 704: 1-1-0 |
| Flash point | > 260 °C (Lit.) |
| LD50 (median dose) | LD50 (median dose): >2,000 mg/kg (oral, rat) |
| NIOSH | Not listed |
| PEL (Permissible) | Not established |
| REL (Recommended) | 50 µg/m3 |
| IDLH (Immediate danger) | Not established |
| Related compounds | |
| Related compounds |
Phosphatidylglycerol Dipalmitoylphosphatidylcholine (DPPC) Sodium Phosphatidylglycerol Dipalmitoylphosphatidylethanolamine (DPPE) Dioleoylphosphatidylglycerol (DOPG) Distearoylphosphatidylglycerol (DSPG) |
Chengguan District, Lanzhou, Gansu, China
