How Is PRP Prepared? Centrifugation and Quality Standards 2026

What Is PRP? Biological Basis and Growth Factors

Platelet-Rich Plasma (PRP) is an autologous biological preparation derived from the patient's own blood, containing a high concentration of platelets. Platelets release dozens of growth factors and bioactive molecules — critical to tissue repair — through their alpha granules and dense granules.

The main growth factors and their functions can be summarized as follows: PDGF (Platelet-Derived Growth Factor) stimulates fibroblast proliferation and tissue repair; VEGF (Vascular Endothelial Growth Factor) promotes new blood vessel formation (angiogenesis); TGF-β (Transforming Growth Factor-beta) regulates collagen synthesis and remodeling; IGF-1 supports cell survival and growth; EGF (Epidermal Growth Factor) accelerates wound healing and epithelialization; FGF (Fibroblast Growth Factor) enhances tissue regeneration and vascularization.

A healthy individual's blood contains an average of 150,000–350,000/μL platelets. The clinical target is to reach at least 3 times this value, and ideally 5–8 times. At Virtuana Clinic (Izmit/Kocaeli), platelet concentration is documented for each session and quality assurance is systematically maintained.

Overview of the PRP Preparation Process: 4 Main Stages

PRP preparation is based on the principle of separating blood components by exploiting their density differences. The four fundamental stages of the process are:

1. Patient preparation and blood draw: Compliance with pre-protocol instructions; venous blood draw into anticoagulant-containing tube
2. Centrifugation (separation): Platelet enrichment via single or double-spin protocol
3. PRP collection and quality control: Aspiration of the platelet-rich fraction; concentration measurement where required
4. Activation and application: Activation with calcium chloride where required; injection or topical application

Every step of this process affects the quality of the final product. Incorrect technique or inadequate equipment reduces the platelet recovery rate, diminishing the treatment's effectiveness.

Pre-Draw Patient Preparation: Protocol and Restrictions

The quality of the PRP preparation process begins before the blood draw. Pre-preparation instructions given to Virtuana Clinic patients in Izmit/Kocaeli, along with their rationale:

• Hydration: Drinking plenty of water in the 24 hours before the procedure (at least 2.5 liters daily) improves platelet quality and blood fluidity; dehydration adversely affects platelet aggregation by increasing viscosity.
• Aspirin and NSAID restriction: Aspirin, ibuprofen, and naproxen (COX inhibitors) should be discontinued 5–7 days before the procedure. These drugs irreversibly inhibit platelet degranulation and cause significant impairment in platelet function tests (PFA-100). Cardiologist approval is mandatory for patients taking aspirin for cardiovascular reasons.
• Alcohol: Alcohol consumption 48 hours before the procedure impairs growth factor response and platelet function; chronic heavy alcohol use negatively affects thrombopoiesis.
• Smoking: Nicotine increases platelet aggregation and impairs capillary circulation, adversely affecting the healing environment. Avoiding smoking for at least 24 hours before the procedure is recommended.
• Blood values: PRP treatment is contraindicated in patients with platelet counts below 100,000/μL. Pre-procedure verification of platelet count via complete blood count (CBC) is standard.

Blood Draw Technique and Anticoagulant Selection

The venous blood draw technique is critically important in PRP preparation. Generally, 20–60 mL of blood is drawn under sterile conditions from the antecubital fossa (median cubital vein at the inner elbow). The volume varies depending on the application area and target size:

• Facial PRP (skin rejuvenation): 15–20 mL
• Scalp PRP (full scalp area): 25–40 mL
• Large joint (knee, shoulder): 40–60 mL
• Tendon/ligament PRP: 20–30 mL

Anticoagulant selection directly affects PRP biology. A comparison of the most commonly used options:

Anticoagulant	Mechanism of Action	Preferred Application	Key Consideration
ACD-A (Citric acid-dextrose)	Ca²⁺ chelation + cell metabolism supported	Aesthetic and scalp PRP — gold standard	pH slightly drops (6.8–7.0)
Sodium citrate (3.8%)	Ca²⁺ chelation	General PRP and joint applications	Concentration (1:9 ratio) is critical
Heparin	Antithrombin III activation	Some orthopedic protocols	May impair growth factor binding
EDTA	Ca²⁺ and Mg²⁺ chelation	Blood count / laboratory testing	Absolutely not preferred for PRP — causes cellular damage

Centrifugation: Comparison of Single-Spin and Double-Spin Protocols

Centrifugation is at the heart of PRP preparation. Blood in the anticoagulant tube is spun at a specific force (g-force) and duration; layers separate according to density differences. In scientific terminology, speed is generally expressed in g (multiples of gravitational acceleration) rather than rpm, because the same g-force corresponds to different rpm values on different devices.

• Single Spin: 200–400 g force for 10 minutes. Blood separates into three layers: erythrocytes (red cells) at the bottom, the platelet- and leukocyte-rich "buffy coat" layer in the middle, and platelet-poor plasma (PPP) at the top. The buffy coat and a small amount of plasma above it are aspirated together. Fast, practical, and requires minimal equipment; platelet concentration increases 2–4 fold.
• Double Spin: The first spin (100–200 g, 10 min) achieves basic separation; the resulting supernatant (upper plasma + buffy coat) is transferred to a second tube and centrifuged again at 400–700 g for 10 minutes. The bottom pellet contains platelet concentrate; it is diluted with a small amount of PPP to obtain the final PRP. Concentration can reach 5–9 fold; however, the process takes longer and excessive centrifugation may cause platelet activation.

At Virtuana Clinic, the protocol is selected based on clinical indication and application area. A single spin generally provides sufficient quality for skin and facial PRP; switching to a double-spin protocol may be considered for hair loss and joint applications.

Platelet Concentration: Clinical Target Values and Classification

The minimum platelet concentration required for PRP efficacy remains debated in the international literature. Dohan Ehrenfest et al.'s 2009 classification and Mishra et al.'s 2012 clinical threshold recommendations are still used as references today:

Platelet Concentration	Classification	Clinical Suitability	Note
1–2x baseline	Low concentration	Insufficient — limited or no clinical effect	Suboptimal kit or technique
3–5x baseline	Standard PRP	Skin rejuvenation, scalp PRP, intra-articular	Target of most clinical protocols
5–8x baseline	High concentration	Chronic tendinopathy, severe hair loss	Requires double-spin protocol
>8x baseline	Super-concentrated	Selected orthopedic indications	Under investigation; very high concentrations may have an inhibitory effect

Important clinical note: There is in vitro evidence that growth factor effect paradoxically decreases at very high concentrations exceeding 1,000,000/μL platelets. Therefore, the "more is better" approach has not been clinically validated.

Leukocyte Content: The P-PRP vs. L-PRP Distinction

White blood cell (leukocyte) content is a critical parameter in PRP classification. Leukocyte content must be consciously regulated according to clinical indication:

• P-PRP (Pure PRP): Leukocyte-depleted formulation (<1×10⁶/μL leukocytes). Pro-inflammatory cytokines (IL-1β, TNF-α) that can inhibit fibroblast proliferation and collagen synthesis are low. Preferred in intra-articular injections, facial PRP, and aesthetic applications; local inflammatory response is minimal.
• L-PRP (Leukocyte-Rich PRP): Has strong antimicrobial and antibiofilm effects due to high neutrophil and monocyte content. May be preferred in tendinopathy accompanied by chronic infection, diabetic wounds, and contaminated connective tissues; however, it should be used cautiously in reactive joint diseases due to its inflammatory potential.

A 2021 systematic review (Fitzpatrick et al., Am J Sports Med) demonstrated that P-PRP provides significantly better cartilage protection and pain reduction compared with L-PRP in intra-articular applications.

PRP Activation: The Difference Between Exogenous and Natural Activation

Physiological (natural) activation occurs when platelets come into contact with tissue collagen, thrombin signals, and local pH changes following injection. This natural activation is sufficient in most clinical scenarios. However, some protocols apply exogenous activation prior to injection:

• Calcium chloride (10% CaCl₂): The most commonly used activator. Mixed with PRP at a 0.05–0.1 mL/mL ratio. Triggers calcium channels in the platelet membrane, initiating degranulation and growth factor release. A fibrin clot also forms; therefore, injection must be completed within 5–10 minutes.
• Thrombin: A powerful and rapid activator; fibrin clot formation is immediate. However, bovine (cattle-derived) thrombin is rarely used in aesthetic practice due to the risk of allergic reaction and potential thrombotic complications.
• Activation-free (Native) PRP: Left to undergo physiological activation. Allows flexibility in injection timing; no risk of clogging since fibrin polymerization has not begun. Multiple studies report no clinically significant difference between native PRP and exogenously activated PRP.

At Virtuana Clinic, individual decisions are made based on application area and indication. An activation-free protocol is generally preferred for skin and scalp applications.

PRP Kit Selection and Certification Standards

There are dozens of different PRP kit systems on the market. Kit quality, platelet recovery rate, and concentration consistency directly affect outcomes. Characteristics to look for in a high-quality PRP kit:

• CE (European Union) or FDA (USA) approval — third-party documentation mandatory
• Closed-system design — contamination risk near zero compared with open-system kits
• Documented platelet recovery rate ≥70% (relative to platelet count at start of blood draw)
• Controlled leukocyte filtration option (ability to prepare P-PRP or L-PRP)
• Lot-based consistency and reproducibility evidence (manufacturer publications or independent lab data)
• Processing time: ideally should not exceed 20 minutes

At Virtuana Clinic, only CE-approved kit systems with documented efficacy in independent clinical publications are used. Internal quality control is applied with each new kit lot, and platelet concentration measurements are documented.

Major Errors That Cause Quality Loss During Preparation

Incorrect technique, inappropriate equipment, and protocol deviations can prevent obtaining high-quality PRP. The most frequently encountered quality issues, their causes, and preventive measures:

Error	Mechanism / Consequence	Prevention
Excessive centrifugation speed (>800 g)	Platelet activation and mechanical damage; growth factors released prematurely	Adherence to kit-specific g-force protocol
Long wait after preparation (>30 min)	Spontaneous activation; growth factors wasted before reaching application site	Inject within maximum 20–25 minutes of preparation
Insufficient blood volume	Low PRP volume and concentration; insufficient coverage for large-area applications	Calculate minimum blood volume per indication and area
Red blood cell contamination	Erythrocyte hemolysis creates pro-inflammatory environment; increases local tissue damage	Adequate centrifugation for clear separation; aspiration away from red cell layer
Contamination / use of open system	Bacterial and fungal contamination; risk of injection site infection	CE-approved closed-system kit, sterile environment, single-use materials
NSAID / aspirin use (pre-procedure)	Persistent inhibition of platelet function; degranulation impaired	5–7-day medication restriction protocol before procedure

Clinical Factors Affecting the Growth Factor Profile

Even with the same centrifuge and kit, PRP quality can vary due to individual differences. The main individual factors affecting growth factor concentration and platelet activity:

• Age: Platelet volume and granule content may decrease after age 50; however, PRP clinical efficacy is maintained.
• Baseline platelet count: A high baseline value (e.g., 350,000/μL) makes it easier to reach the target concentration.
• Chronic diseases: Diabetes, liver disease, and renal failure may impair platelet function.
• Nutritional status: Iron, zinc, and vitamin D deficiency adversely affect platelet quality.
• Physical activity level: Regular exercise improves platelet turnover.

Frequently Asked Questions: PRP Preparation Process

How much blood is needed? It varies between 15–60 mL depending on the indication. 15–20 mL for facial PRP, 25–40 mL for scalp PRP, and 40–60 mL for large joint applications is standard.

How long does centrifugation take? 10 minutes for a single-spin protocol, 20–25 minutes total for a double-spin protocol. Total preparation time including blood draw is 20–35 minutes.

How quickly must PRP be used after preparation? Activation-free PRP should ideally be administered within 20–25 minutes; activated PRP must be used within 5–10 minutes as fibrin polymerization has begun.

Can PRP be frozen? No. Freezing damages the platelet membrane and permanently destroys growth factor activity. Fresh PRP must be prepared separately for each session.

Does PRP preparation require a special room? Centrifugation can be performed in a standard clinical setting; however, use of a closed-system kit and sterile technique are mandatory. A laboratory-grade clean room is not required.

Virtuana Clinic PRP Preparation Protocol

At Virtuana Clinic in Kocaeli/Izmit, the PRP preparation process is conducted in accordance with international guidelines (ISTH, ICCBBA standards, and Dohan Ehrenfest classification). Our standard process:

1. Determination of baseline platelet value via complete blood count and patient eligibility check
2. Use of CE-approved closed-system kits (lot control and expiration date verification)
3. Personalized spin protocol selection (single or double spin) based on the patient's baseline platelet value and indication
4. Recording of PRP volume obtained and concentration estimate at each session
5. Documentation of P-PRP or L-PRP formulation choice in clinical records per indication
6. Injection within maximum 20 minutes of preparation
7. Written patient information with post-procedure care protocol and a 2-week follow-up appointment

Which Patients Are Not Suitable for PRP?

Certain conditions represent absolute or relative contraindications during the PRP preparation and application process:

Condition	Contraindication Type	Explanation
Thrombocytopenia (<100,000/μL)	Absolute	Adequate concentration cannot be achieved; procedure is ineffective
Active cancer / hematologic malignancy	Absolute	PDGF and VEGF may accelerate tumor progression
Acute infection / sepsis	Absolute	Risk of infection spread
Warfarin / NOAC therapy	Relative	Assessment required following cardiologist approval
Pregnancy and breastfeeding	Relative	Insufficient safety data; aesthetic indications deferred
Autoimmune thrombocytopenic purpura (ITP)	Absolute	Platelet dysfunction renders PRP ineffective

Lifestyle and Nutritional Recommendations to Improve PRP Quality

Platelet quality and growth factor content are directly related to your overall health status. To get the best results from treatment:

• Omega-3-rich diet: Eating fish 2–3 times per week (salmon, sardines), regular consumption of walnuts and flaxseed supports platelet membrane flexibility and function
• Regular physical activity: 150 minutes of moderate-intensity aerobic exercise per week improves platelet turnover and raises baseline VEGF levels
• Smoking and alcohol restriction: Both significantly and adversely affect platelet quality, vascular response, and growth factor efficacy
• Adequate sleep (7–9 hours): Growth hormone release peaks at night; sleep deprivation weakens tissue repair capacity
• Vitamin D and zinc: Vitamin D deficiency may impair platelet activity; zinc supplementation contributes to follicle and tissue healing
• Hydration: Daily intake of at least 2.5 liters of water normalizes blood viscosity, facilitating both blood draw and improving tissue perfusion

This article is for informational purposes only. Please consult a qualified physician for treatment decisions.